A look in to the future 🔮 A lot of time you need to make a system that can send out to yourself or other users , specifically events related to changes in your database. and make this ridiculously easy. notifications based on events Postgres Phoenix By the end of this post you will have: short Setup a Phoenix 1.3 project Setup a broadcast function and trigger in Postgres Used a GenServer to listen for broadcasts from Postgres Used Bamboo to send emails to yourself when users signs up or changes their payment plan. Getting Setup Before you start Please make sure you have the following installed and/or ready to go: Elixir Phoenix PostgreSQL A valid account SendGrid Initialize the project Lets create a new Phoenix 1.3 project called pub_sub_demo mix phx.new pub_sub_demo cd pub_sub_demo mix ecto.create Add Two Additional Dependencies Next we want to add to help with decoding strings sent from the database and to help us send emails. HTTPoison Bamboo To do this in your file add the following to your : mix.exs deps {:httpoison, "~> 1.0"},{:bamboo, "~> 0.8"} Also update the section to include extra_applications :bamboo extra_applications: [:logger, :runtime_tools, :bamboo] Create a model Finally lets create the model we will be using to show off all of this broadcasting goodness. User mix phx.gen.context Accounts User users name:string payment_plan:string Note: We created the _User_ in a new context called _Accounts_ . If you are unfamiliar with contexts they are nothing to be afraid of just a convention phoenix uses to group functionality. They are not special, just a way to bag functions together. Kick it off! Migrate the database, grab your dependencies and lets go! mix ecto.migrate Note: You should now be able to navigate to _localhost:4000_ and see your application running. Though for the purposes of this demo you wont really be viewing any screens. Broadcast Changes with Postgres The whole idea of this is for Postgres to let know when things have changed. To do so we need to set up two things: US A function that takes an action ( , , ) performed on a row for the purpose of broadcasting it outside of the database. INSERT UPDATE DELETE A trigger that calls this function when an action has occurred on a specific table. Create the Ecto Migration mix ecto.gen.migration broadcast_users_table_changes Add the Function and Trigger Update the migration file you created above to include the following If you want to better understand what is occurring here check out this blog post by @kaisersly which largely is the inspiration for what you are reading here: https://medium.com/@kaisersly/postgrex-notifications-759574f5796e Listen for Changes Now that we have our database broadcasting changes that occur on our table we need to be able to listen and act on the same channel. Thankfully Postgrex provides this by default using . users Postgrex.Notifications To use this we must create a responsible for listening to and acting on the messages broadcast. GenServer Postgrex Creating our GenServer Create the file and populate it with the following: lib/pub_sub_demo/pub_sub/listener.ex For now all that this does is listen on a channel provided and log the messages broadcast to that channel. Next lets configure this as a Worker and give it the channel it will listen to. Hook up the listener Update the file so that it starts the we just defined with the appropriate channel. application.ex Listener users_changes See it in Action You should now be able to start your application again by running: mix ecto.migratemix phx.server Then any change you make to the table via Postgres’s CLI should be output to our Applications . users stdout Listening for Specific Actions While it’s nice to be able to see that occurs in the database often we only care about a small subset of these changes. Specifically for this demo: everything User created User subscription updated Luckily Elixir’s pattern matching provides a wonderfully simple way to cut down on all the noise and focus exactly on the shape of data you’re looking for. What we want to do is update to send the payload to a function that will match on the events that matter. handle_info The above only acts on only the exact events we are looking for and outputs a specific message to our log. Anything else is ignored. Link it up to an email service Standard out is nice but in a running application you don’t want to be combing logs for events that your business cares about, you want to be notified in realtime. Lets hook our messages up to an email provider so that we get a notification right in our inbox when a user signs up or upgrades their plan. The Elixir library and service make this far too easy. Bamboo Send Grid Setup Bamboo Add the following to your file config.exs Note: Bamboo offers many more adapters than just Send Grid if you have a different preference. https://github.com/thoughtbot/bamboo#adapters Create a file in your folder mailer.ex pub_sub_demo Sending emails from our Listener Update in to send our log messages to our own email address. handle_user_changes listener.ex Run it for a Final Time Now if you create or update a user in your table you should see emails appear in your SendGrid logs. users Thats it! Conclusion The concept of broadcasting events directly from your database isn’t something new and as a result this type of functionality is available to you in any language and framework. But! The core features and functionality of Elixir and Phoenix make using database events much easier and more reasonable than I have found in any other system. Pattern Matching and OTP principles are both simple and powerful and I encourage anyone to take a deep dive into them when possible. 🧞‍ This is open source! you can find it here on Github ❤️ I only write about programming and remote work. If you I won’t waste your time. follow me on Twitter

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Developers produced some really great resources for each other in 2017. After 8+ years reading and curating developer content, I thought it was about time that I compile an end-of-year list with the scores of resource links that I share on Twitter and Reddit throughout the year. I look through dozens of developer newsletters, subreddits, Medium publications, and HN each week — so I don’t miss much. Hope you find some gems you didn’t catch initially in 2017! –General Dev– Libraries.io, version 2 Search over 311 million rows of metadata about open source projects and the network of dependency data that connects them all in this easy-to-understand interface. In 2017 Library.io had its second open data release, so I’m including it even though the project didn’t originally start in 2017. You can use it to understand how various open source projects are used throughout an ecosystem. Great for new contributors GitHub made an awesome move by creating a page that finally answers this question many budding developers have: “What open source projects can I contribute to?” They’ve crunched and analyzed their data to determine which projects have a history and reputation for being welcoming to new open source contributors. The Art of Comments A really good perspective on how and why to write useful comments in code. Computer Scientist’s Trivia This is the kind of trivia from CS class that’s useful to know but asinine to make people memorize for . Brush up on this stuff and see if it can help you improve your day-to-day code by showing you where deeper bugs and inefficiencies can occur. technical interviews dev-books.com {WARNING: Commenters have informed me that this site uses your computer to mine bitcoin when you visit. If you still want to check it out, install an extension like . Hopefully they can’t circumvent that yet.} Somebody had an excellent idea to scan over 40 million questions on Stack Overflow for any book references. Think of it as a data-driven popularity ranking for the best developer books. No Coin A guide to RESTful API design Over 35 tools and resources for designing good RESTful APIs and keeping up with the API space. I collaborated with the author who built this list and I know that it is continually updated. Programming Talks To anyone who likes this resource list so far — you need to check out the “Awesome” lists on GitHub if you’re not already aware of them. Start with Sindre Sorhus’s . Programming Talks is a GitHub “awesome list” of programming video presentations sorted by language. The author of the list seems to like more academic languages like Haskell, Python, and Clojure, since there’s a large list of talks for those languages, but all the main ones are well-represented. Awesome list of Awesome lists The System Design Primer This repo is a collection resources to help you learn how to build systems at scale. It also includes study materials for system design questions in technical interviews. The Right Way to Select Technology, An Excerpt Although it’s only one chapter of an entire book on selecting technologies for your technology stack, it’s still a good article to help guide your mindset. Readings in Database Systems “The Red Book”, 5th Edition It’s the first update to the Red Book in over ten years. This collection of chapters includes opinionated takes on both classic and cutting-edge research in the field of data management. The Unofficial MySQL 8.0 Optimizer Guide Some unofficial but very good docs on how to use and understand the query optimizer in MySQL 8.0 –Web Performance– The State of the Web If there’s one web performance resource you can’t miss from 2017, it’s Karolina Szczur’s collection of tactics for impactful performance improvements. Everything by Addy Osmani His stuff isn’t just about web performance, but if you develop in JS, you need to be reading Addy’s blog. Measuring web performance; it’s really quite simple An attempt to simplify and focus the topic of web performance to make it more accessible for those who are overwhelmed by some of the complexities discussed in the community. Front End Performance Checklist 2017 So much good advice for setting your front-end performance goals. I think there’ll be a new one soon since this one has been around for just over a year now. Not that I expect any huge differences. A Comprehensive Guide to Font Loading Strategies It may not sound like the most riveting topic, but it’s actually very digestible and heavily bulleted. You’re going to need it if you want to check all the boxes on that Front End Performance Checklist. The Browser Hacker’s Guide To Instantly Loading Everything Instantly loading everything — sounds pretty great. Hear about some JS performance strategies from Addy Osmani. It’s one of several excellent talks he gave in 2017. Reducing CSS bundle size 70% by cutting the class names and using scope isolation One cunning web developer figured out how Google reduces its CSS bundle size and shows you how to do it yourself. –Web Development– Modern JS Cheatsheet This resource isn’t a learn-JS-from-scratch cheatsheet. It’s more focused on the next step after basics — recognizing some of the things you might encounter in more modern JS codebases. 30 seconds of code A curated collection of useful JavaScript snippets that you can understand in 30 seconds or less. Currently there are over 100. Awesome Awesome Node.js It looks like Awesome Awesome Node.js is an attempt to gather all of the best list resources on Node.js, in addition to the existing . So meta… Awesome Node.js repo Node.js Best Practices A curated list of content that covers Node best practices. Checklist: Node.JS production best practices This checklist for running Node.js in production is well-designed, using best practices gleaned from high ranking blog posts. React’s Five Fingers of Death. Master these five concepts, then master React. A nice primer that distills the five key concepts you need to grasp before starting to develop in React. The Beginner’s Guide to ReactJS This React fundamentals course by Kent C. Dodds — A JS developer/speaker of PayPal fame — is now free forever. Best ReactJS books, tutorials, courses & videos 2017 Curated by ReactDOM: The ReactJS, React Native & GraphQL newsletter. Best Vue.js books, tutorials & courses 2017 Also curated by ReactDOM. A 10 minute primer to JavaScript modules, module formats, module loaders and module bundlers Planning to start using JS modules? Start here. The Survive.js Webpack Book Survive.js… an appropriate name when you think about all the churn in the JS space. There are also survive.js books on and in addition to this webpack book, but there are plenty of resources on those topics, and I think the webpack book stands out among its competitors. Webpack is one of the most useful tools in the JS ecosytem you can learn. maintenance React Front End Checklist Unlike the previous checklist on front-end , this one is focused on best practices for page structure and design. Plus, it’s an actual checklist with checkboxes. Fancy. performance What Web Can Do Today Here’s another useful website that helps you quickly determine if a particular browser supports a specific web standard. My giant JavaScript Basics course is now live on YouTube. And it’s 100% free. freeCodeCamp has a lot of free resources on its YouTube and Medium pages. This resource is probably a good place to start if you want to get into web development or brush up on JS basics. How Flexbox works — explained with big, colorful, animated gifs I know the internet is littered with Flexbox tutorials, but this one from 2017 has very helpful animated gifs to help you visualize the concepts while you read about them. Your Regular WordPress Maintenance Checklist Wordpress continues to evolve, and with it — your security and performance maintenance need to evolve as well. WTFJS Inspired by Brian Leroux’s talk , this list contains “funny and tricky” JavaScript examples that can teach you a lot about the language. I tried to end this section with something a little more entertaining! “WTFJS” at dotJS 2012 –Security– The Basics of Web Application Security You know when the Martin Fowler blog breaks down a topic, you need to start taking this shit seriously. Also, how have you not studied the new yet? OWASP top 10 Web Developer Security Checklist And here’s a good, simplified checklist to go with the “Basics” article above. Wargames Here’s 12 unique games for improving your security skills. If you’ve been around the security community at all, you’ll know that games are a common tool for learning. –Testing– Awesome Testing The collection of “awesome lists” for testing grew substantially in 2017. Here’s the basic primer that anyone new to testing in the software industry (or needing a refresher) should read. Awesome Visual Regression Testing Visual regression testing can be tricky to carry out. This list is not tailored to a specific role, so it’s useful for anyone in UX, testing, or development. Awesome Static Analysis More teams need to use static analysis tools, and this curated list of static analysis tools, linters, and code quality checkers is a great place to start. Five Factor Testing This could be a useful framework for discussing test strategy if your testing strategies aren’t already super-mature. –Ops/DevOps/SRE– How to Deploy Software A funny, whimsical, and very readable guide to building a general deployment strategy that isn’t outdated and stupid. Monitoring the SRE Golden Signals This is an ebook in slideshare format outlining how to monitor the “golden signals” aka. important metrics of an app. Apparently a lot of people talk about the golden signals, but not how to monitor them. Best practices for staging environments Staging environments are considered a best practice, but why? This article gives you a lot of good reasons along with great general techniques and advice for running your own staging environment. Minimum Viable Analytics A lot of teams know they need UX and operational analytics for their apps, but they don’t know what metrics they need, and they might not know how to get them either. This article gives you the baseline analytics that every application development team should have, and it tells you how to get them. specific Onboarding New Site Reliability Engineers This is a short article, but it’s useful if you’re starting to hire and use SREs for the first time. –Data Science– Every single Machine Learning course on the internet, ranked by your reviews There are tons of really good machine learning courses on the web now. Here’s a list that can help you sort through some of the noise. Essential Cheat Sheets for Machine Learning and Deep Learning Engineers A list of cheatsheets for popular ML and DL libraries. Python Data Science Handbook Python is perhaps the most common programming language used for data science. While this book was published in late 2016, it became free online in 2017. How to Get Your First Data Science Job You’ve got plenty of resources here, but do you know how to land a data scienmce job? This guide gives you a good starting point (you have to register, but after that it’s free) Learn data science: 44 essential resources for developers I collaborated with the author to build this data science resource list. It has all the best resources and courses from the last couple of years. There are also new resources in the comments since the article was published. datavis.tools A curated guide to data visualization tools and resources. –Soft Skills/Teamwork– Periodic Table of Agile Principles and Practices Any topic turned into a periodic table is pretty cool in my book. This one organizes and defines the more granular practices of XP, Agile, Lean, and other work styles. You might find a few interesting tactics that you never knew about. Awesome Diversity A list of organizations, conferences, actionable resources, and more related to improving diversity in tech. I think it’s a really important and often-overlooked or dismissed topic in our field, so I decided to write up two articles myself on and underrepresented team members. hiring keeping Culture Codes This repository contains many interesting and inspiring employee handbooks and culture decks. Some of the companies include Netflix, Spotify, Valve, GitHub, and Google. I summarized the lessons from several of these culture decks and handbooks in last year. (The site was literally published in the same month that I wrote that article. Same idea at the same time.) an article Mental Models: The Best Way to Make Intelligent Decisions (113 Models Explained) Developers and managers can benefit from learning mental models. They help us make better business and technical decisions. Public Product Road Map: A How to Guide Ever heard of public product road maps? Read about them here and see how they’re done. The Side Project Marketing Checklist 2017 was the year of the “side hustle” (or at least the year where no one would shut up about it). So if you’re looking to market your own side project, there’s no better place to start than with this checklist. 7 Powerful Ways To Get Feedback From Users Some of these strategies might seem like overkill or unnecessary work, but if you want to be sure that you’re making something that people actually want, then you need to be a little extreme sometimes. A free guide to building awesome communities Maybe your side hustle is to start a blog or community. This guide can help you get started with that. –Career– Stack Overflow’s “Calculate your salary” Tool Using data from their annual dev survey, Stack Overflow built a salary calculator web app that shows you typical salaries for your experience level, location, specific technologies, and education. Trending Developer Skills, Based on my Analysis of “Ask HN: Who’s Hiring?” One blogger decided to take Hacker News’ weekly “Who’s Hiring” posts and count the requested skill keywords. It should give you a good look at the skills and stacks that startups are looking for right now. Become a productive programmer, and work saner hours A multi-article series by Itamar Turner-Trauring on how to live your best dev life. Lots of good “learning to learn” material, as well as productivity tips, career advice, and work/life balance advice. Hiring Without Whiteboards I wrote an summarizing the widespread backlash against the “whiteboard interview”. This GitHub repo contains a list of companies that don’t do whiteboard interviews. It helps job seekers who don’t want to support companies that use these technical interview strategies. article in 2016 Rethinking the Developer Career Path Instead of counting the number of days someone’s been paid to write code and massaging that into a title, Randall Koutnik suggests an alternative way for looking at the trajectory of a developer’s career. In this talk, he describes three stages of a developer’s life that can help developers reconceptualize their own growth, and help managers understand a better way to promote developers. That’s a wrap. If you want to see what developer resources I find in 2018, follow me on twitter: @mpron

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The Top 66 Developer Resources From 2017

I used to think is a hard process, but when I actually tried it out I realized it’s not hard at all. Well, dockerizing isn’t an actual name, but it’s an easy way of saying containerizing a setup using docker. I didn’t come up with that name but my colleagues did, I’m merely using it since it’s actually easier to call it that :). dockerizing Anyhow, as I mentioned earlier once you actually start doing it, it doesn’t look hard at all. Let me guide you through it step by step using docker and WSO2 products. First of all, install and in your computer. I will not go through this procedure in detail since you can find dozens of articles online explaining how to do it. Once you are done with this step, create a folder (I will call it ) and copy the zip file of the WSO2 product into it. Create a file by the name inside and just leave it empty. I will explain what to put in this file, later in the article. Then create another directory inside the and copy all the changed configuration files into that (I will call this directory “resources” from this point on-wards). Go into the resources directory and create a file in this directory named product-setup.sh (You can name this whatever you want :) ) docker docker-compose service_root Dockerfile service_root, service_root Once you are done with the initial skeleton, open the product-setup.sh file in a text editor, use command to install all the required packages inside the container. For example, in this case you need the unzip program to extract the product zip file inside the container. It’s also important to run command before running the installation commands to ensure the package manager cache is updated. A very minimal example product-setup.sh file will look as follows. apt-get install apt-get update apt-get updateapt-get install -y unzip unzip /tmp/wso2ei-6.1.1.zip -d /wso2 mv -f /tmp/resources/changed_config_files /wso2/wso2ei-6.1.1/path_to_the_relevant_config Don’t worry about how the product zip file got into /tmp , I will explain it later in the article. From this, the main idea you have to get into your head is, first you need to install relevant applications, then unzip the product zip to a desired folder and overwrite the relevant config files in the product distribution, with the updated config files you put to the resources directory. Rename “changed_config_files” to the file names and “path_to_the_relevant_config” to the path of the files in the distribution. After completing the product-setup.sh file, lets look at the . This is the file docker calls when it’s building the docker image. And in this file, we can also, specify the start up scripts for the docker image. I will first give an example that suits the current context and explain it line by line. Dockerfile FROM airdock/oracle-jdk:1.8 COPY wso2ei-6.1.1.zip /tmpADD resources /tmp/resources RUN chmod +x /tmp/resources/product-setup.sh && /tmp/resources/product-setup.shRUN chmod +x /tmp/resources/wait.sh CMD ["sh", "/wso2/wso2ei-6.1.1/bin/integrator.sh"] The first ‘ command specifies the base docker images to be used for the current docker image. This can change based on the requirement. Since I’m trying to run a product that needs java on the docker container, I picked an image with java. If you you need some other service, then you can use a different pre-built image. Please visit to explore the available pre-built images. You just have to select an image from here, then find the import address then use “ ” command to use that pre-built image. FROM’ docker-hub FROM The command is used to copy the product distribution into the docker image. In here, I’m copying it into the folder inside the container. Then add the resources directory to the container. These paths are used in the product-setup.sh file to perform various tasks. Then give execution access to the product-setup.sh and run it. The “ command specifies that the has to run upon start of the container. ‘COPY’ /tmp CMD” integrator.sh Now that we are done with the and the we can move on to define any other services that we need to run. Go out of the directory that contains the , create folders for the rest of the services and in the same way we did earlier, you can define the rest of the services as well. After defining the setup for all the services we can use docker-compose to build and run those services. First we need to define the file outside the directories. You can refer to documentation to get a better idea about the In this article I will briefly explain how you can use docker-compose to build and run these containers defined. Please see the example file below. product-setup.sh Dockerfile, Dockerfile docker-compose.yml service_root this docker-compose.yml. docker-compose.yml version: '2' services:integrator-service:image: integrator-imgcontainer_name: integrator-svcbuild: ./ei-setupdepends_on:- analytics-service- mb-serviceports:- 9443:9443- 8243:8243- 8280:8280 First line specifies which version of the docker-compose definitions we are using. Then under services you can define details about the services which you would like to build and start using docker-compose. In this file, under we give a name to our service (in this case “ ”). “Image” specifies the name of the build image, “container_name” specifies the name of the container, “build” specifies the name of the folder for a particular service, “depends_on” specifies which services needs to start before the current service starts. This is a bit tricky though, because when you list down a set of services that needs to start first, docker-compose makes sure to start them before the current service, but it doesn’t make sure those services are up and running before it starts the current service. Therefore, you might run into issues if you are using dependent services, but in that case all you have to do is add a line in the start script of your service to wait till these dependent services are up and running. Then in the “ports” section, you can specify which ports needs to be exposed to the outside ( is the syntax to expose ports. services integrator-service product_port:container_port Another important thing is, if you want to communicate between these services, you can refer to them as . Protocol can be http, tcp, etc. and the service name and the ports has to be as defined in the . protocol://service_name:port docker-compose.yml Now, you are all set, you can run the command to build and run the docker containers. docker-compose build && docker-compose up, I hope this article was helpful in understanding how to containerize WSO2 products using docker. If there are any questions or any problems you run into while trying this out, please put them in the comments section. I will try and answer all the questions as soon as possible.

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How To: Dockerize WSO2 products

This post has received a tremendous amount of outcry against my claiming a “victor” in the war between programming languages. While I admit, my title may have been intended to spark controversy and may be “click-baity”, I do still want to emphasize that . this post is not about how JS is the “best” language It is simply about the sheer territory it has covered and the ways in which it has allowed the once-simple front-end dev to do so much more. It’s a versatility I have truly grown to love in my career and one I feel obligated to encourage. And so… In the world of programming, there was a war waged long ago. Since the advent of the computer, scientists have been searching for the perfect programming language. One after the other, a new language was created to accommodate some purpose. And with that new language came a new era of technology, a bolstering community, a million libraries and open-source contributions, and — inevitably — a new limitation. Since the ancient days of assembly programming to the Java Applets and Flash Abominations (and I was a Flash developer at one point…) that dominated the web for so long, we have seen languages come and go for no reason more than that their usefulness had worn out. The world moved in a different direction… And that once shiny, new language was now old-hat, with developers dwindling and a new kid on the block starting to make some noise. Now, JavaScript has been around for — literally — decades. So, you might be wondering, “Where is he going with this?” Well, this post isn’t really about “JavaScript.” Nor is it about the many languages that have risen and fallen before it. Nor is it about how JavaScript is “new and shiny.” This post is about Node. And we really need to start distinguishing that. Because Node is something else. It is not just a language. It is an ecosystem. And that is what this post is about. Well, not entirely. I’m not going to go into detail on the million and a half reasons the ecosystem is the most innovative facilitator of open-source collaboration the world has ever seen. No, that’s a topic for another day. For now, I’m just going illustrate how Node has already won the age-old war for the perfect language by traversing five key territories of modern-era programming: The Web React, Angular, Vue React, Angular, & Vue are easily the most important front-end frameworks in existence today. Collectively, Facebook, Google, and the FOSS community have developed mind-blowingly efficient tools for developing interactive user-interfaces. As a result, practically everything you do on the web today is served up by a highly-interactive, aesthetically pleasing, and easy-to-use interface. And these frameworks have been made possible entirely because of the Node ecosystem, which you already knew. You see, there is no question that JavaScript has dominated front-end web development for an eternity, but React, Angular, & Vue have taken it to another level. This is the age of the UI. The age where front-end developers no longer shy away from building complex, single-page web applications and full-fledged suites of software. Where I was once a web developer, I am now a software developer. And like that… Node won the web. Mobile React Native Not only is this section going to illuminate the mobile successes of Node, but it is also going to make another crucial point: Node is cross-platform. And not just in the, “Oh, cool it works on my phone!” kind of way. Not even in the, “Whoa, my phone, tablet, laptop, and TV can all use YouTube!” kind of way. Node is cross-platform in the most important way possible. It is truly cross-platform for developers. The people that actually build that “oh, cool” and “whoa” stuff mentioned above frackin’ LOVE this. React Native is just one example of a framework developed in the Node ecosystem that bridges the gap between front-end development and mobile app development in a way that no other frameworks have before. The biggest strain on developing for mobile has always been the pull of the web. However, with React Native and the Node ecosystem, a developer can build literally one application that is compatible with the web, iOS, & Android. No other language offers this kind of versatility. And like that… Node won mobile. Desktop Electron Of course, not everything happens on the web. Desktop applications are also crucially important to the way we operate in today’s technologically-dependent world. But why should we treat the desktop any different when the web is now capable of serving up fully-functional applications? It was just a matter of time, really, before JavaScript caught up to the performance needs of the desktop. And so, Electron was born. Sure, there are still more efficient languages to use when programming for desktop, but for a majority of the applications we use today, JavaScript is more than adequate. Thanks to Cheng Zhao & Github, a framework was created that is changing the face of desktop computing. Not only has Electron added desktop application development to the web developer’s already growing repertoire, but it has done so in a way that is wholly cross-OS compatible. While Windows is still the most pervasive OS today, Mac has been on a steady rise for 15 years, and . In addition, little toys like the Raspberry Pi are causing Linux to pop up in more than just a few previously Windows-or-Mac-only households. I think you can see why cross-OS development is such a huge advantage… . more and more developers are switching to Linux every day (as I just did) and this is just the start Now we’ve got the web, mobile, and desktop fully covered by the Node ecosystem. One skill-set that is capable of building the same UI in all of these places. And like that… Node won desktop. Back-end ExpressJS I don’t want to get into an exposé here about the countless packages available on NPM (Node Package Manager) that facilitate back-end development, so instead, I’m only going to mention ExpressJS, and this is to make one simple, but profound point: Node was built for the back-end. And JavaScript in the Node ecosystem has become such a versatile tool that it has been used to literally develop its own server application. Now, this may not seem like the most impressive feat, but let’s consider that up until the creation of Node, JavaScript was pretty much browser-only. It didn’t need to perform complex server-side operations like database fetching, image transforms, or compression. … But now it could And — as with several examples above — this dramatic simplification of code sharing and reuse has had some remarkable side-effects. One such side-effect is . server-side rendering Did you catch that? server-side rendering What do those two things have in common? Well traditionally, nothing. These two responsibilities have always been relegated to their “front-end” (JavaScript) or “back-end” (PHP, Java, Python, Ruby, etc, etc etc) handlers. Often maintained by two completely separate teams. Very different people, back-end & front-end developers… But no longer! Thanks to Node, we are now able to assemble complex user-interfaces on the server-side before a user’s browser ever needs to render a thing. This is why the web is so snappy nowadays. Because Node has the boundary between back-end and front-end. erased And like that… Node won back-end. Gaming Unity 3D I saved this one for last because it’s not really a “Node” thing, but a JavaScript thing and I wanted to close on a slightly broader note: The successes of JavaScript are not a result of it being superior to other languages. Its successes are a direct result of how accommodating it has been to virtually every community. JavaScript developers are not purists. We like our language the way it is(n’t); versionally-fragmented, transpiler-dependent, cross-platform, bleeding-edge, ever-evolving, and going where no language has gone before. Like game development! When Unity 3D first introduced their JavaScript-based “UnityScript” as a means of game development, I saw then, that JavaScript was going to do some really cool things. This was one of it’s first major forays into non-web development, and it was a clear sign of things to come. It was a clear sign that JavaScript could do more than just open fly-out menus and tweak font sizes on a page. It could do more than let you like this post and heart that picture. It could handle immersive, cross-platform gaming experiences. And those same developers that were once restricted to Chrome, Firefox, & Internet Exploder were suddenly game developers. And while Unity did recently announce they’ll be dropping UnityScript support, I’m still going to say: And like that… JavaScript won gaming. OK, maybe not. But it’s not the 12th round, yet, is it? Veni, Vidi, Vici I don’t know when the conquests will cease, but Node is on a rampage. It is toppling one development conundrum after another and paving the way for a world of software development where one language rules them all. I do feel I need to reiterate before trolls, though — in case it was overlooked: JavaScript is NOT the best language for every job. The strength of JavaScript comes from its versatility. It comes from the open-armed community that has embraced this classless little, polymorphic scripting language and turned it into the most powerful development ecosystem available today. ? I’d love to hear about it in the comments. Disagree Otherwise, please share a few claps and show your support for ! the world’s most innovative language My name is Jonny Asmar and I want to sincerely thank you for taking the time to read my post! I started writing code in Notepad over 15 years ago and never stopped. While I mostly work in React/Redux & Node, I have a passion for technology that goes far beyond UI development — this has been my effort to share that passion with you. You can learn more about me at JonnyAsmar.com , see some of my code on GitHub , or reach out to me at jonnyasmar@me.com .

Assembly

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JavaScript Has Already Won

_A community for developers looking to put WebAssembly to use today._www.wasmrocks.com Games Using WebGL shaders in WebAssembly Rust WebAssembly A* Pathfinding Demo An Asteroids clone written in Rust, rendering to an SVG canvas. Funky Karts — a fun browser game written in WebAssembly. WASM game: Worldy Cup on AirConsole CreaturePack: High Performance 2D WebGL Character Animation with WebAssembly Let’s write Pong in WebAssembly Blend4Web applications with physics will now invoke the binary WebAssembly build by default FEDAY — WebAssembly在白鹭引擎的实战（PDF） What’s new with WebAssembly portable code WebAssembly Canvas2D example WebAssembly Is Overdue: Thoughts on JavaScript for Large Projects The Next Generation of Web Gaming

13 Games Built on WebAssembly

Amazon

Apache

Fetch

ORANGE

Velocity

AWS AppSync — Up and Running with GraphQL in the Cloud

In software engineering, remote working makes a lot of sense since, most of the time, you only need a computer and an internet connection to perform your duties. So there are fewer reasons to force people to sit in a predefined office everyday. Consequently, it has become an important feature of a lot of IT jobs, even in Belgium, while it is definitely not the most forward looking job market. That said, most of the time, the remote working offer only apply to a part of the week (1 or 2 days a week seems to be the most frequent proposition here). Nevertheless, it definitely is getting a hold in most companies. There is a lot of good to say about remote working, and I see a lot of rabid defence of the practice. I agree with most of it. That said, I have been working remotely for a little more than 5 years now, and I now must acknowledge that it does not come without stress. This might come as a surprise for some, but in the end, I think that remote working has taken some toll on me over the last two years, especially when I went almost fully remote for a year, from June 2016 to June 2017. So, what can make remote working stressful? Dehumanisation If you are working remotely, communication tends to stick to structured channels: the chats, the daily standup, maybe a few global meeting (retrospective, company status) every other week, Jira for the tasks and bug reports and lots and lots of emails. This works well to accomplish structured tasks, but you might definitely feel disconnected from the company sometimes. The fact that most of this communication happens in written form, or in front of groups makes them unsuitable for small talk or more informal information. This can hamper your work, as just chatting about the atmosphere at work can deliver very important information about the smooth progress of projects, but most importantly, it can prevent you to feel as part of a community. Also, written exchanges are more prone to misinterpretation, even with people you know very well. Not to mention that, if you already spend your day typing on a keyboard to accomplish your technical programming tasks, it might become annoying to have your communication done in written form too: you might end up feeling like a text processing machine. So, after some time working remotely, it happened multiple times to me to miss the coffee chats, previously felt as unproductive wastes of time. I felt detached from the team, especially when the teams I worked with were made of multiple people working in the same office/place, and seeming to have fun. Interruptions and multitasking When working remotely as a developer, the chat (usually Slack or Hipchat) quickly becomes your lifeline to the company: that is the way most people will try to contact you. And to me, being responsive on the chat accomplishes the same as being on time at work in an office: it gives an image of reliability. It also implies that if you do not really want to give the impression that you are taking a lot of breaks, you might find yourself checking your notifications a lot while taking lunch for example, while if people had seen you working the whole morning, or if you were just talking with colleagues at that point, you would not feel the need to be so responsive. I actually often realized that other colleagues working remotely were criticized because they were not answering very quickly on the chat. A part of the problem is that on a chat, people do not see you physically, so they cannot really estimate if you are at a good moment to be interrupted. So, you are interrupted a lot, and if you are a bit like me, you feel forced to answer quickly. So, you interrupt your work a lot. And in case you do not know it: interruptions are loathed by programmers, since it is really bad for their productivity as it breaks their focus. The other problem with this remote chat setup is that people do not know if you are already speaking with somebody else. I cannot count the number of times where I have been juggling three different conversations at the same time, which, to me, can become stressful, especially when I do have tasks to finish by the end of the day. Also, I must mention that there are also often “leisure” chats, created to host non-work stuff (usually, a lot of memes) that can become very, very chatty. At least, I feel that it is really sane to mute these chats most of the time, but when you come back, catching on everything that was said can be a daunting task, while it might be your only opportunity to have some “office spirit” that you are missing by being a remote worker. Overworking There are two types of obligations you get when you are taking a job: , where you commit to give a certain result by a given date. Typically, for a developer, accomplishing a sprint with a given set of bugs/features to develop. Obligations of results where you mainly commit to spend some of your time everyday on your work, and you just give the results you managed to produce over that time. Obligations of means, I am not naive, and I know that in the end, in software engineering, most jobs are really about results (you get fired in the end if you produce nothing), and not means, but in remote working, since people are not seeing you work, you might feel more obliged to show results everyday, even if it forces you to work way past 8 hours a day. As an example, I cannot count the number of times where a configuration problem or a customer call took me a few hours of my day, but I still felt forced to finish the task I committed to do on that day, so that nobody could assume that I was slacking off instead of working. I feel that if people had seen me in front of my computer all day, I would have felt more relaxed about deciding to finish the task the next days. will This leads to two things for me: being really appreciated for the reliability of my output, and … being seriously overworked. According to Jason Fried from Basecamp, this is the true challenge of managing remote workers: . people who work too hard In the end, this all amounts for me to the question of trust: your employer trusted you a lot, allowing you to work on your own terms , and in exchange, I have always felt compelled to actually work a lot more than if I was in an office. Being a stay at home dad When you spend a good part of your time at home, your family sees you as more available than they should. Even if you have places dedicated to work that should be forbidden to your kids, it is still tempting to come ask you “just a little something”. Especially for kids, it is hard to compartimentalize their home. Actually, it is hard for me too … This can make video calls a bit stressing, when you are talking with a customer for example, and your kids end up just appearing behind you on video. Here is the most well known example of this: I also know some people have problems resisting the need to perform home duties, like cleaning the kitchen, for example. This has never been too much an issue for me, but on the other hand, this created tension with my wife from time to time, since it was difficult for her to understand how I could have left a dirty dish the whole day on the dining room table while I was actually at home. Answer: I was working and avoiding interruptions… Loneliness. Working at home can mean a lot of loneliness. I do enjoy being alone quite a lot, but even for me, after two weeks of only seeing colleagues through my screen, and then my family at night, I end up feeling quite sad. I miss feeling integrated in a community of pairs. Social networks might help you fight that loneliness a little, but on the other hand, pausing only with social networks is not different enough physically from working on your computer. Moreover, it is also well known that spending more time on social networks rather tends to make you . less happy than the opposite In the end, I really started to hate being alone most of the time and have felt it to be quite bad for my mental health and my mood. This is a phenomenon. well documented One of the most recommended way to fight this is to work in . To me, they are a mixed bag: they cost some good money (that your employer might agree to pay, or not), and often ask for commitment (you usually need to register for at least a month). They can create social link (and for me, they created a lot of work opportunity, especially the B ), but at the risk of feeling a bit too much like a vacation camp, with activities everyday (cooking, massages, meet ups, …), to force people to socialise. coworking spaces etacowork Notice that I have been to coworking spaces where there was no socialisation, and gave up rather quickly, since it seemed rather pointless to go somewhere to avoid loneliness, and then not talk to anybody all day. So, I am ambiguous on the subject of forced socialisation. Another problem with coworking spaces is that you might introduce long commute times in your life again, then work with headphones all day to avoid being distracted, barely taking a break because you lost time commuting, and feeling awkward for not having spoken with anybody while being there for the community. Not to mention that video calls are more difficult to do in these settings, since you usually lack a place to be alone, there is always a bit of noise, and people might be annoyed by your call. Moreover, sometimes, there are things that you do not want to say in front of strangers… Stress to decide where you work everyday. This might be just me, but not knowing where I will be working everyday, and having to think about which hardware I need to take with me (example: keyboards, DVI adapters, chargers) has led to a lot of problems, by removing the predictability of being all the time in the same office. Also, notice that I think that working in coffee shops is a bad idea, at least for full days. There is usually too much noise, and I do not like feeling obligated to take something to eat/drink every hour (your mileage may vary), and the chairs are bad for your back… . You never leave “work” When you work remotely, you do not leave your working place at night. On top of that, if you work with people in different timezones, you might end up communicating a lot with people while your day is already over (I did that for months when working with people based in New York or SF). It often makes a lot of sense, since otherwise, you might have too few time to communicate with your team, and this can really hamper the progress of a project, but it means that there is no time in the day free of working concerns, which again, is bad for your mental health over the long run. Also, working at home does not leave you time to cool off while coming back home from work. For me, the ideal duration of a commute is 15 to 20 minutes. That leaves you some time to walk, and so, do at least a bit of physical exercise, and to change your thoughts a little bit. There were a lot of evenings where I ended up going from a video meeting to a family dinner in 30 seconds, and I must says that it is not always easy to give a good attention to my kids in such occasions. Career risk Working remotely makes you less visible in your company. If you intend to have more responsibility in your job over time, this can end up being a problem. I worked for example for a company where I felt that people “in the office” were preferred for promotions. So, you have to consider that too when working remotely. On a more humorous note, you have to consider than working in your sweat pants for years, unshaved and without too much time constraints might make you unfit to go back to work in an office. You might suffer from some degradation of your social skills: See the whole comic about working at home here: http://theoatmeal.com/comics/working_home Conclusion Globally, I have enjoyed working remotely over the last few years, and it has been a boon to my family and my wife while my kids were small. I do think it made possible for my wife and me to pursue our careers without too much hassle, as I was more available to take care of the kids when they were sick, which happens a lot in the infancy years. This flexibility came to me at the price of catching up on work in the evenings and weekends, but it was still very much appreciated. Remote working also allowed me to join teams of great quality that I would not have found in my local job market and to work on ambitious projects. So, all in all, I am still a great fan. On the other hand, after more than 5 years of remote working, I have to say that it really took a toll on my mental comfort sometimes, and that had some unwanted impact on my family relationships, mainly irritability on my side. Before you experience it, it might seem as the perfect solution for your life, but as I tried to explain, there are a lots of unforeseen ways in which it can create stress. To summarize, the main problem for me is to feel like a text processing machine, receiving mails, Jira tickets and chat messages as input and writing code as output, without the human interactions needed to make it more meaningful. I do not like becoming a kind of a . remote developer black box

Basecamp

BOON

Instagram

Slack

The Stress of Remote Working

Image credit: Pixabay Make no mistake about it: Cybercrime is a growing concern for businesses of all sizes. In 2016 alone, global losses due to cybercrime amounted to , according to the FBI. Growth estimates vary from a more conservative to a less optimistic . $1.3 trillion $2 trillion by 2019 $6 trillion by 2021 One thing is for sure: Malicious players will always be on their toes, trying to find the next big exploit, and trying their best to profit from malware or social-based attacks. It is no surprise that the cybersecurity industry is also a growing one. According to CSO Online, security spending will amount to a cumulative . This will include acquisition of products and services that fight or mitigate the effects of cyberattacks. $1 trillion from 2017 to 2021 However, as the cybercrime threat landscape is evolving, we all need to realize how quickly we are evolving along with these threats. In a , we are told that cybercriminals will naturally gravitate toward the most efficient and risk-averse mode of operation. In these modern times, the most financially-rewarding and scalable attacks involve extortion and data theft. recent blog post by Imperva In this regard, extortion usually involves ransomware, wherein a malicious agent locks down or encrypts the user’s own data within the user’s own machine or server until a payment is made. This can also include distributed denial-of-service (DDoS) attacks, in which a user’s infrastructure is bombarded with traffic rendering it useless unless a payment is made. Digital assets are also a prime target — these could easily be stolen by malicious insiders or even through unwitting and careless users who are compromised. It almost seems like an unwinnable battle. Attackers are coming from everywhere, and no matter how careful we are with our data and with our digital assets, there will always be a potential attack vector. Today, the trend is moving toward a decentralized and distributed approach to computing. We now store our digital assets on the cloud, and our applications are likewise running off the cloud or even on some distributed infrastructure like blockchains. Our employees and colleagues use mobile devices — laptops, tablets, smartphones, and even internet-of-things (IoT) devices, in managing this data. The threat landscape suddenly became more spread-out. It will no longer be simple for a Chief Security Officer or IT manager to secure the office data and infrastructure if there is no local infrastructure to speak of, in the first place. When everything is running on the cloud, how well can all this data be secured? Traditionally, businesses relied on virtual private networks, in order to wall-in users within a tunneled connection. The problem here is that a VPN can perform very poorly in terms of speed and accessibility, compared to a direct internet connection. These can also come with expensive licensing and deployment costs. The trend today is moving toward having everything as-a-service. Cloud models involve either software-, platform-, and infrastructure-as-a-service, for example. When it comes to ensuring the security of digital assets, an emerging trend would involve a firewall-as-a-service (FWaaS), which eliminates the concept of a firewall appliance that has been a limiting aspect of enterprise and business security for decades. , addresses this emerging need by actually building its cloud-based firewall atop its existing global cloud infrastructure. This is established as a global SD-WAN or software-defined wide area network, which can secure all WAN and internet-based traffic, regardless of where a user’s device is, or how he accesses data. Cato Networks, a provider of FWaaS solutions Deploying the firewall as a service that runs on the cloud itself has several advantages. First, it negates the need for appliance-based firewalls, which do not work well in distributed environments. Secondly, it lets IT managers control the deployment from a single point, even if there are hundreds or thousands of multiple devices and connections all connecting and accessing data from different points in the world. A related service is or WAF, which protects both cloud and on-premises infrastructure from application-layer attacks. The two services actually rely on the same distributed infrastructure in delivering both mainstream and last-mile protection service for its subscribers. A WAF, however, focuses on filtering incoming traffic in order to protect infrastructure against threats such as cross-site scripting, SQL injections, and other major threats that could compromise data. Incapsula’s web application firewall Subscription-based approach to security and other trends With security solutions shifting away from the appliance an on-premises approach, we have likewise moved toward a subscription-based approach for ensuring the integrity of our data and infrastructure. Gone are the days of paying a premium for the latest security software. Even when that approach entailed regular updates, today the standard approach mostly involves a drop-in solution wherein you subscribe, then you integrate the solution into your infrastructure (usually by routing all traffic through the provider), and waiting for it to do its magic. In fact, going beyond the traditional cloud-based services cited above, another emerging trend today is the tokenization of digital services. With a blockchain-based approach, for example, one common approach to acquiring services is through an ad hoc or per-unit approach, which can be easily accomplished through tokenization. Customers pay using crypto assets, cryptocurrency or crypto tokens whenever they utilize a servce. A few examples of security-oriented services that run off the blockchain are and , for instance. Guardtime aims to replace existing key-based authentication with verification based on cryptographic hashing algorithms. Nebulis, meanwhile, aims to replace the current DNS infrastructure with a distributed platform to mitigate the risk of DNS nodes going down due to DDoS attacks. GuardTime Nebulis Changing business models will benefit businesses Capable cybersecurity solutions used to be the domain of enterprises and larger businesses that have the capital to spend on expensive products and services. With the current trend shifting toward subscriptions, cyber security can likewise be treated more as an operational expense rather than a capital-intensive one. This means businesses of all sizes can benefit from increased security without a very big budget. And as for the emerging blockchain-based approaches to security, time will tell if the up-and-coming companies can deliver as promised and whether a purely decentralized approach will be the best means to address growing digital threats. For now, with businesses all going to the cloud, it only makes sense for us to deploy our security solutions mainly through the cloud, as well.

Target

Forget Buying Security Solutions; Everything Comes as-a-Service Now

Prehistory Hello everyone! Most recently, I ran into a problem: for unexplained reasons, the memory card began to move all files to the LOST.DIR folder without any extensions. For a long time, there accumulated more than 500 files of different types: pictures, video, audio, documents. It was impossible to understand the format of the independently, so I started looking for a way to solve this problem programmatically. file Looking for decision I did not want to use ready-made solutions in the form of web services or programs, so there was an idea to write a console utility that would go through all the files and install the extensions automatically. was chosen to write the utility. The search for suitable modules and libraries did not bring results for several reasons: Python Lack of support from the developer Excessive functionality Lack of support for new versions of Python Excessive code complexity Of the many libraries, python-magic is very popular (almost 1000 stars on GitHub). It’s a wrapper for the libmagic library. But it’s impossible to use python-magic under Windows without the DLL for the Unix library. So this option wasn’t good enough. Solution of the problem Proceeding from the above, I decided not to use third-party libraries and modules and solve the problem without them. After a short search of information on how to implement this task, the only true way was to determine the format by the signature of the file, also called “magic number”. The file signature is a set of bytes that provides a definition of the file format. The signature has the following form in hexadecimal notation: 50 4D 4F 43 43 4D 4F 43 Fortunately, there are two good sites on the Internet with a lot of signatures of different formats. The most common formats became the goal.As it turned out, some signatures are suitable for different file formats, such as the signature of Microsoft Office files. Based on this, in some cases it will be necessary to return a list of suitable file extensions. print(get("D:\\some_ms_office_document")) # prints ['doc', 'ppt', 'xls'] Also, often the signatures have an offset from the beginning of the file like 3GP multimedia container. 1. Compiling a list of data As a list of data, I decided to use a JSON file, with the ‘data’ object, whose value will be an array of objects of the following form: {"format": "jpg", "offset": 0, "signature": ["FF D8 FF E0", "FF D8 FF E1", "FF D8 FF E2", "FF D8 FF E8"]} Where: format — file format; offset — offset of the signature from the beginning of the file; signature — an array of suitable signatures for the specified file format. 2. Writing an utility Import the necessary modules: import osimport json Read a list of data: abspath = os.path.abspath(os.path.dirname(__file__))data = json.loads(open(os.path.join(abspath, "data.json"), "r", encoding="utf-8").read())["data"] Great, the data list is loaded. Now we read the file as an array of bytes. We will only read the first 32 bytes, since the determination of common formats doesn’t require more, and full reading of a large file will take a long time. file = open("path_to_the_file", "rb").read(32) If you print ‘file’ variable, you will see something similar to this: \x90\x00\x03\x00\x00\x00\x04 Now bytes must be converted to a hexadecimal system: hex_bytes = " ".join(['{:02X}'.format(byte) for byte in file]) Next, we create a list in which the appropriate formats will be added: out = [] And now we create a structure that will cyclically determine the file format: for element in data:        for signature in element["signature"]:            offset = element["offset"]*2+element["offset"]            if signature == hex_bytes[offset:len(signature)+offset].upper():                out.append(element["format"]) About this string: offset = element["offset"]*2+element["offset"] Since our bytes are represented as a string, and two symbols represent one byte, we multiply the offset by 2 and add the number of spaces between the “bytes”. And the only thing that remains for us is to output a list of suitable formats, which is represented by the ‘out’ variable. print(out) # prints something like ['extension_1', 'extension_2'] Conclusion As it turned out, various projects are faced with the need to recognize the file format, so I decided to release my solution in open-source as a module for Python called fleep . You can install the module using the standard python utility ‘pip’: link to the GitHub page pip install fleep Also there are examples of usage and a complete list of supported file formats on the GitHub project page.I improve fleep every day, adding new features and formats. You can use it in your project :) Thank you for attention! P.S. I would be glad to hear your opinion about my module.P.P.S. English is not my native language, so, excuse me for any mistakes :)

Microsoft

Determining file format using Python

What is Autocomplete ? Let’s take a very common example. Whenever you go to and start typing, a drop-down appears which lists the suggestions. Those suggestions are related to the query and help the user in completing his query. google Suggestions when typing on Google Autocomplete as the says wikipedia Autocomplete, or word completion, is a feature in which an application predicts the rest of a word a user is typing It is also known as or . It helps in navigating or guiding a user by prompting them with likely completions and alternatives to the text as they are typing it. It reduces the amount of character a user needs to type before executing any search actions, thereby enhancing the experience of users. Search as you type Type Ahead Search search AutoCompletion can be implemented by using any database. In this post, we will use to build autocomplete functionality. Elasticsearch Elasticsearch is an open source, distributed and JSON based search engine built on top of . Lucene Approaches There can be various approaches to build autocomplete functionality in Elasticsearch. We will discuss the following approaches. Prefix Query Edge Ngram Completion Suggester Prefix Query This approach involves using a against a custom field. The value for this field can be stored as a keyword so that multiple terms(words) are stored together as a single term. This can be accomplished by using . This approach has some disadvantages. prefix query keyword tokeniser Since the matching is supported only at the beginning of the term, one cannot match the query in the of the text. middle This type of query is not optimised for and may result in increased latency. large dataset Since this is a query, won’t be filtered out. One workaround to deal with this approach can be using an aggregation query to group results and then filtering out results. This involves a bit of processing though on the server side. duplicate results Edge Ngrams This approach involves using at index and search time. When indexing the document, a custom analyser with an filter can be applied. At search time, can be applied. which prevents the query from being split. different analysers edge n-gram standard analyser Edge N-gram tokeniser first breaks the text down into words on custom characters (space, special characters, etc..) and then keeps the n-gram from the start of the string only. This approach works well for matching query in the middle of the text as well. This approach is generally fast for queries but may result in slower indexing and in large index storage. Completion Suggester Elasticsearch is shipped with an in-house solution called . It uses an in-memory data structure called (FST). Elasticsearch stores FST on a per segment basis, which means suggestions scale horizontally as more new nodes are added. Completion Suggester Finite State Transducer Some of the things to keep in mind when implementing Completion Suggester The autosuggest items should have types as its field type. completion An input field can have various canonical or alias name for a single term. Weights can be defined with each document to control their ranking. Storing all the terms in lowercase helps in the case-insensitive match. Context suggesters can be enabled to support filtering or boosting by certain criteria. This approach is the ideal approach to implement autocomplete functionality, however, it also has certain disadvantages Matching always starts at the beginning of the text. So search for in marvels movie dataset will not yield any result. One way to overcome is tokenizing the input text on space and keep all the phrases as canonical names. This way will be stored as america Captain America: Civil War Highlighting of the matched words are not supported. No sorting mechanism is available. The only way to sort suggestions is via weights. This creates a problem when any custom sorting like alphabetical sort or sort by context is required. Implementation Let’s implement the above approaches in Elasticsearch. We will be using Marvels movie data to build our sample index. For easy reference, here is the Spider-Man: Homecoming Ant-man and the Wasp Avengers: Infinity War Part 2 Captain Marvel Black Panther Avengers: Infinity War Thor: Ragnarok Guardians of the Galaxy Vol 2 Doctor Strange Captain America: Civil War Ant-Man Avengers: Age of Ultron Guardians of the Galaxy Captain America: The Winter Soldier Thor: The Dark World Iron Man 3 Marvel’s The Avengers Captain America: The First Avenger Thor Iron Man 2 The Incredible Hulk Iron Man We will be creating an index with type movies marvels. If we see the mapping, we will observe that name is a nested field which contains several field, each analysed in a different way. Field is analysed using a Keyword tokenizer, hence it will be used for Approach name.keywordstring Prefix Query Field is analysed using Edge Ngram tokenizer, hence it will be used for Approach. name.edgengram Edge Ngram Field is stored as a completion type, hence it will be used for Completion Suggester. name.completion We will index all our movies by using Let’s start with Prefix Query approach and try finding movie beginning with . th Query will be This will result in the following movie Thor: The Dark World Thor: Ragnarok The Incredible Hulk Thor The result is fair, but some movies like , are because prefix query only matches at the beginning of the text and not in the middle. Captain America: The Winter Soldier Guardians of the Galaxy missed Lets try finding another movie beginning with . am Here we do not get any results, although satisfy this condition. This confirms the point that Prefix query cannot be used to match in the middle of the text. Captain America Let's run the same search but with Edge Ngram Approach. am Here we get the following result Captain America: The First Avenger Captain America: Civil War Captain America: The Winter Soldier Let’s try finding for Captain America again, but this time with a bigger phrase captain america the Using Edge N-gram approach, we get the following movies Captain America: The Winter Soldier Captain America: The First Avenger Captain America: Civil War Thor: The Dark World Captain Marvel Guardians of the Galaxy The Incredible Hulk Guardians of the Galaxy Vol 2 Ant-man and the Wasp Marvel’s The Avengers If we observe our phrase, only the first two suggestion makes sense. The reason for so many terms getting matched is the functioning of clause. match includes all the documents which contain . Since the field is analysed using ngram, more suggestions(if present) will get included as well. match captain OR america OR the Let’s try using the suggestion query for the same phrase . Suggestion query is written in a slightly different way. captain america the We get the following movies as result Captain America: The First Avenger Captain America: The Winter Soldier Let’s try the same query, but this time with a typo . captain amrica the The above returns no result because no support for fuzziness is present. We can update the query to include support for fuzziness in the following way movie-suggest The above query returns the following results Captain America: The First Avenger Captain America: The Winter Soldier Conclusion Various approaches can be used to implement autocomplete functionality in ElasticSearch. Completion Suggester covers most of the cases which are required in implementing a fully functional and fast autocomplete.

Elasticsearch: Building AutoComplete functionality

This tweet made me think. The whole thread is worth a read. I’m sure many developers who are excited by code sometimes resonate with these feelings. I promised a reply too lengthy for Twitter, and here it is. First, some context: I remember first getting excited about computers in the Christmas of around 1982 or 1983 when my sister (8 years my older) got a Commodore VIC-20. I remember being 4 or 5 years old and thinking I would likely use it “better” than her in her early teens. Every time I touched a computer from then on I got excited, but I didn’t really get into learning how they worked properly until I was about 11 or 12. By the age of 18 I already knew C well enough to top classes in my fresher year at University, and by the age of 28 I had worked in the civil service, academia, multiple small businesses, peculiar corners of the World (the Falkland Islands are lovely), and was running a company helping small startups figure out what this tech revolution was all about. I ended up CTO’ing for a few startups, and then in about 2014/2015 I realised I missed coding, resigned from my job, took a 30%-ish pay cut and went back to being a senior software engineer at a larger firm, where I remain. Each of the tweets Saron sends in that thread encapsulates some aspect of my career that to an outsider can look one way, but actually, something else is going on. Take for example: Interestingly, I can respond to this with a tweet I made myself just a little while back: Junior developers start with this expectation that if they just learn to code, they’ll be done and then get their hours and they’ll progress career wise. This is nonsense. Coding for a living is learning for a living. If you don’t like learning , turn back now, or try and get a jump over into something less demanding from a learning perspective. every single day The more you code, the more you realise there are whole mathematical, theoretical, engineering and creative universes you do not understand, will never get around to understanding and therefore there is no point in pretending you do, will or can understand. If you took me and another developer with a similar history, but the other party had spent their entire lives coding at banks, and put us in a pub together to have a chat, we’d have surprisingly little common ground. We could talk about language semantics a bit. I’d know a lot more about web and app facing stuff more than they do. They might know more about compliance and perhaps strategies more appropriate for Enterprise setups. I’m spending a lot of time working on event sourcing at the moment, so we’d have common ground there but we’d call things by different names. Add a game developer to our table, and we’re likely going to sit quietly for a while until we all remember we all like . Rick & Morty And that’s what I think you’re normally seeing when you see a self-deprecating senior. They don’t actually think they’re terrible, they just know their limitations and enjoy working within them, and have got past the point of bullshitting you into thinking they’re experts at everything. Next up in that thread: The least important thing about a piece of software is the code. Sorry, but it’s true, and the sooner everybody who comes to the career realises that, the more productive, happy and grounded they will be. Saying that code is the most important thing is like saying the most important part of a new building is the architect’s blueprints. You’re not going to get far without them, but there is a hell of a lot of other stuff an architect has to do to make sure clients, local citizens, authorities, other architects, etc. are all pleased with the building. Nobody won an architect’s prize for a good drawing, and a piece of code that serves a need nobody has or does it in a way that unwittingly leaks personal data or breaks machines is not going to win high praise. Language semantics are the equivalent of the language of an architect’s drawing. Just as how an architect passes drawings to construction workers to realise, we pass our code to interpreters and compilers. Just how some architects want to excel at civil engineering, some coders will get into the working pieces of languages. Just how pre-fabricated houses are good value for money for those who don’t care about architecture per se, you can go a long way with downloading or copying/pasting stuff and stitching it together. Ultimately you have a responsibility as a professional to realise that your code has audience expectations, and it has responsibilities to that audience and others, and that’s why it exists. That doesn’t mean you can’t be proud of how you met or exceeded those expectations or responsibilities by expressing those needs in code itself, but until you accept in your heart of hearts that your job is to serve them as primary concerns through the language of code, and the code itself is no important than ink and paper is to writing, you are going to find this a brutal career. I used to say software engineering is 80% communication and 20% writing code. I now think it’s more like 95%/5% when done well, it’s just that more of the communication can be done with other engineers through well designed and architected code. I came back to coding because it’s the best way I know to express myself whilst making a living at it. I can play a little piano badly, I’m a terrible artist, and whilst I enjoy writing it doesn’t pay the bills. Now, years ago, I had stacks of side projects lined up. Very few of them got worked on because real life gets in the way. Some of us just get more tired as we get older, some of us have families, I got ill without realising it and for the last two years have basically been having an issue that culminated in my losing the ability to walk (I’m mostly fine now, more ). here The point is, experience tells us getting too excited about those big ideas might lead to frustration as we might not get to work on them. Don’t let that stop you being excited about those things. Go build as much as you possibly can. If you can and are willing, be not just productive, but prolific. Your energy will wane as you age. That’s OK. Your priorities in life will change. That’s OK. You will narrow your field of interest. That might be OK, it might not be, it’s normally best to keep your mind open to new fields especially in the first 30 years or so of your career. Do not confuse though, those people who have prioritised other aspects of their life for people who have given up on the potential of what a developer with a good idea and the energy and skill to execute it well can do. Just remember though, we all know the names of Gates and Zuckerberg because there are only two of them: the odds are long, the glory is great, and it’s yours if you want it. But, you know, it’s OK to not do that if you want to hang out with people, and in my personal experience, people are nicer to hang out with than computers. Think about that. I tell a story sometimes about an encounter I had a couple of years ago. I was doing STEM outreach for the Royal Society via Salford University. One morning I found myself doing an assembly at Manchester Islamic High School for Girls. Facing a room of 11–14 year old girls, most in head dress, some in burkas, I pulled up pictures of Ada Lovelace, Grace Hopper, Gates, Zuck and others. I told those girls about how I saw their potential: Few things you can choose to do in your life will allow you to have such an impact on the betterment of humanity, if you choose to better humanity with these skills. With the laptop or PC you likely already have at home and some knowledge, you can create experiences for an audience of billions at virtually no cost other than your time. Those experiences can educate, entertain or enhance. They can turn people into superhumans of virtual Worlds in a game or titans of industry inside a spreadsheet. You can build mental muscles that leverage our capability as a species. Writing code sits at a fascinating and beautiful intersection between the analytical world of Science and the expressive potential of the creative arts. It is professional, rewarding, and well-paid. If you learn to code, and you enjoy it, the limit of your expression is entirely of your own making. After giving an impassioned 20 minute speech on these lines, I sat down to listen to the next presenter: a woman from British Gas encouraging them to become boiler repair personnel so they could get their “own uniform and drive a van”. I sighed at my society, picked up my laptop and left. But I’m telling you now Saron, and all who feel as you do, that my thoughts remain unchanged and I’m now telling these things. you Yes, I self-deprecate, yes I am too busy to get excited by absolutely everything, and yes I do prioritise my health and a balance in life to throw myself into the abyss of creatively coding like a maniac. But do not ever mistake this for thinking we are signalling to you that you are naively making a mistake, that your excitement will eventually wane despite you not wanting it to, or that those of us with more experience than you right now think your enthusiasm is misplaced. Godspeed, and good luck.

An open letter to less experienced developers

Intro I will show how to code. upload files to Dropbox from Python Why do I need this? Currently, I am only using for all my web services and also as my private git server. WebFaction I wanted to make an automatic . backup of my git repositories to Dropbox Dropbox App I order to upload files to Dropbox you need to have an . access token And for the access token, you need to register your . app on DBX platform All of this must be done on Dropbox website. The first step is to go to and press “Create App” button. https://www.dropbox.com/developers/apps/ Step 1 Just click “Create app” button Step 2 We will use Dropbox API. We will choose “App folder” because we will just upload one backup to Dropbox, we do not need full access to all our files. Name your app and click “Create App” button. Step 3 We will use defaults settings, here we will get the access token so, click “Generate access token” button. Step 4 Now you have your access token, you will need it in your code, so copy it. Step 5 Now we have our “my_git_backup” Dropbox app. pip install pip install dropbox pip install fabric It is always recommended to inside python. use virtual environments At least I use them always. Code For code sample please go to http://buklijas.info/blog/2017/12/01/automatic-backup-of-git-repositories-to-dropbox-with-python/ How I run this automatically I personally run this command from . crontab once per day 35 02 * * * /home/user_name/code/venv/bin/fab -f /home/user_name/code/fabfile git_backup_to_dropbox Conclusion This can be used for . backup of any folder as zip file automaticaly to Dropbox For any questions, please write them in comments. Originally published at buklijas.info on December 1, 2017.

Dropbox

Automatic backup of git repositories to Dropbox with Python

2017 is ending, and I would introduce my iOS toolset that I used during this year and that I will continue to use during the coming year.Please note this list is not exhaustive and only includes some of the most and libraries that I discovered during this year or that I find really helpful during my work. development tools Tools I don’t know why some people despise , but I find it really useful to manage my git repos, and currently is my favorite tool for GIT. It has everything I need. SourceTree : I tried a lot of editors during the past year, from Sublime to Atom, from TextMate to TextWrangler, but I found that VS Code meets my needs. Is not perfect, but it’s a good combination of practicality and speed. Visual Studio Code : we use it in my development team at Dottori.it, and is really helpful for build API requests through testing, documentation, and sharing. Postman : I literally love it. It preserves copied data from clipboard and allows easy access to those data through a shortcut. That dramatically increase your daily copy/paste workflow, and I’m more productive. PasteBox Libraries : I started to use it when I joined Dottori.it. Now every asynchronous piece of code is used in combination with PromiseKit. PromiseKit : is a wrapper of UIButton written by me during 2017. It allows you to create custom and complex buttons with custom attributes, directly added to the iOS Interface Builder, very easy to integrate into every project. PMSuperButton : is found it really helpful during the development of . It’s a super customizable calendar that meets everyone’s needs. JTAppleCalendar AgendaDottori : is a library that allows you to convert your model objects (classes and structs) to and from JSON. I started using it from Swift 2, and now with Swift 4 that support is less relevant, but already useful because support a lot of features like custom transformations. ObjectMapper Codable : in the new version of AgendaDottori (rewritten from scratch in Swift 4), we needed a mobile database where to store all the events in a calendar. Potentially a lot of data. I tried CoreData and Realm, but after that i see Couchbase Lite 2, literally a “full-featured embedded NoSQL database that runs locally on mobile devices”, i started to use it and it matched all my needs. Couchbase Lite : I used it to generate fake data in DEBUG mode and in my unit tests. Really helpful and with a lot of data that can be generated. Fakery : like the GitHub page description is an Android-like toast with a very simple interface. Is really useful to use it to inform a user of an action. Toaster : last but not least, I can not fail to mention the best (for me) library to manage dates on Swift. Is created by my friend Daniele, and I use it for all my iOS projects. SwiftDate Websites & Services : in January 2017 after the release of the mobile SDK, I started to work on the mobile app of , a startup launched with some friends in Ireland. One of our major features for the mobile app that is useful for the users that want to offers customer support from mobile, is to have push notifications. After my experience with Firebase Cloud Messaging (that not match totally my needs), we tried OneSignal that is exceptional. They offer realtime analytics, unlimited push notifications, delivery automation, localization, full API, unlimited segments, A/B testing, and much more. Amazing. OneSignal Customerly : in Dottori.it we use a lot the deep linking, and when we need to create a new one, usually we use Firebase. The problem with AgendaDottori was that Firebase offers only one link for the project, and the project of Firebase include two apps, that there is a conflict. Then, this year we tried to move the deep link engine on Branch.io, a service that provides the leading mobile linking platform, with solutions that unify user experience and measurement across different devices, platforms, and channels. Simple and effective. Branch.io : english is not my native language, and I’m not perfect when I write in English, in particular when there is a lot to write. This service helped me a lot to increase the quality of my written English and to fix some errors. Grammarly : is a website where every week you can read a new interview with one person that start a business from a side project. I really love it because open my mind to some aspect that I not considered, and is helpful to know how much they earned with every single business that they started. Is inspirational and motivational. Indie Hackers Extra: useful articles and links Web developer roadmap Joel Spolky quotes How to Make a Web Crawler in Swift 🕷 Web Developer Security Checklist PMAlertController The Epic Guide to Bootstrapping a SaaS Startup from Scratch Marketing for Engineers Listening: Levitate by Imagine Dragons Mr. Brightside by The Killers It’s My Life by Bon Jovi Everlong by Foo Fighters Under The Bridge by Red Hot Chili Peppers Hotel California by Eagles you for ! you enjoyed the article as much as I did 🤠 Thank reading I hope If you want to follow me in social media, here are some links. github , twitter , linkedin The last year I read a , and this year I wanted to create my personal list. useful post by Durul Dalknat

Apple

OneSignal

My Development Toolset 2018 for iOS

computing is a fairly new concept that has somewhat exploded in terms of popularity. This is in-part due to AWS’ Serverless offering, as well as Azure’s newly released . Serverless AWS Lambda Functions Serverless computing essentially allows you to define individual API endpoints that perform any number of actions once triggered. This could be as simple as a “Hello World” endpoint or as complex as an online store transaction endpoint that handles credit-card payments. I believe the combination of the following factors are going to cause an explosion in the number of developers leveraging Serverless options in order to extend their existing systems. Parallels With The Unity Game Engine When I first started getting into programming 8 or so years ago, I was focused on game programming. I read up on the forums and bought the books , and . C++ Primer Plus Beginning C++ Through Game Programming OpenGL Programming Guide When I was just getting started I ultimately believed that I could do everything from the physics and gameplay side to the AI and graphics rendering systems. I was overly optimistic and unfortunately I never completed a full game. However I was able to learn a hell of a lot and as I was entering university, a game engine called came out and started to revolutionize the way game developers developed their games. Unity3D By the end of 2016, of games had been developed and released onto the Steam platform. By abstracting away some of the key complexities of game development such as the graphics rendering system, game developers were able to make far further strides than they would have been should they have attempted to go it alone. thousands Serverless computing will have as big an impact on software development as Unity3D had on Game Development. Horizontally Scalable When it comes to services such as AWS Lambda, when you expose an endpoint, you don’t necessarily have to worry about massive surges in traffic. The underlying system will automatically handle things such as load-balancing and the provisioning of appropriate infrastructure in order to meet any massive surges in traffic. Pay For What You Use When it comes to AWS , you pay for what you use. There is no need to provision a tonne of t2.small instances running your service and autoscaling groups that will duplicate said instances in the event of surges. pricing This all comes for free. Underlying Infrastructure Managed For You These Serverless cloud providers constantly monitor and manage the underlying fleet of servers running your code. They apply security patches as and when they are available. This helps to minimize the risk of 0-day exploits hitting your company hard and somewhat reduces underlying infrastructure security concerns. If you were running your own EC2 instances you would have to apply security patches yourself and you would have to keep on top of them as they come out. This can be a time drain and can reduce the amount of time you spend actually producing new products and services. Language Agnostic Endpoints Thankfully, every endpoint you set up can use a different language runtime. If you have Python developers, feel free to let them create endpoints written purely in Python, if you have Go developers, let them do likewise. AWS Lambda supports Node.js, Java, C#, Python and more recently Golang so the option to enable your developers to write in the language they are most comfortable with is certainly there. These endpoints can be written in a number of different languages which allows you to specifically choose the language best fitted for the job. This alone is a major win. Changing the World, Faster As we lower the friction between having an amazing idea and implementing it so that it is production ready, we will maximise the speed at which newer technologies can evolve and subsequently make their mark on the world. Conclusion These are just a few key points that make Serverless computing an incredibly attractive option for all developers to consider when developing new systems. Obviously there will be some reasons why certain applications will never be able to migrate to a serverless but I’m hoping this article has at least made you consider serverless for those scenarios where it is possible! architecture Let me know what you think in the comments section below or by tweeting me: . I’m also on LinkedIn: for those of you wanting to connect! Elliot Forbes https://www.linkedin.com/in/elliotforbes/

How Serverless Computing will Change the World in 2018

Yesterday I wrote a explaining, when not to use ECS (Entity Component System). Lot’s of people told me that even though, the post is interesting, it is very theoretical. So today I decided to compare the thought process of writing something in OOP style and ECS style on an example. blog post As an example I would like to take a — before your game / app starts the user has to enter username and password, we send it to back end validate it and only than it is ok to start playing / using the app. log in process First let’s consider I am in SDK team, I need to write a “module” which other developers in my company, or even people from other companies will buy and use. In this case I need to create a simple to understand abstraction, which hides the complexity / implementation details. In such case it is best to follow the typical top down OOP approach. I introduce a class, which is the main interface for the user. In best case, as a user, I will instantiate the class and at some point, it will tell me that user is successfully logged in. It is a black box to me, it will take over UI, networking, persisting data and maybe give me some possibilities to configure it according to some special needs, but otherwise it is pretty much opaque. LogIn LogIn Now let’s consider me an application developer. Log in process is only one of the features I need to implement. In this case I would rather follow the ECS bottom up approach, where I start thinking about the data I will need. And don’t forget — data is not only application state, it is also events and dependencies. So, from current requirements we can assume that we will have: User name Password Send credentials event User token, which we get from backend Login form renderer Now we can think about networking, if we already have some infrastructure for networking in-place, we can reuse it. If not, we can consider to keep it part of login process systems, or build a networking system which expects networking request components. Same applies to persistence. Logic wise we could have something like: Show log in system Send login system Persist token system Load token system Ask to check credentials system Notify login succeeded system As we are building this bottom up and for our self, we can build it flexible and testable, it would be easy to bypass the login process, or test only small parts of the process. We are not hiding the state, we don’t put abstract easy to understand things first. We decompose the problem in it’s smallest parts and let it work on a global state. This however implies that it will be harder to make generic solution out of it. We could say: Well, we will just take those component and class definitions and put them into a separate / reusable module. But this is not always that simple — specifically if we have a shared networking components and systems in our app. Further more, it is just a collection of things, which form something big, user will need to understand those small things anyways. We could also put something like our OOP class on top, which will aggregate / hide the components and systems. Then we have an OOP approach with ECS underneath. This feels like a Frankenstein monster though. I guess it is ok to do in some cases, but I believe keeping to one paradigm is a better choice. LogIn Having sad that, I just recalled building such a Frankenstein monster myself. When we were sharing code for BackEnd validation, we build a stateless worker which received game state, configuration, user events and returned new game state or an error if the events were not plausible and we suggested the player was cheating. This stateless worker was a pure function for our BackEnd. Internally it did a small re-simulation of the game, based on components and systems. So FP from the outside, ECS on the inside. The short self reflecting episode underlines the conclusion of my . It is all about thought process. In FP I would concentrate on immutable state and functions which will transform it. In OOP I concentrate on abstractions, defining classes which encapsulate state and expose methods. In ECS, I concentrate at components and systems I will need to solve the given problem, elevating data representation as the key to solution not the code. previous more theoretical blog post

Keep

ECS vs. OOP by example

Snapshot from website Story Many cryptocurrency traders and check out the prices regularly because they know a day in this Wild West means a full month in the traditional investment space. hodlers I personally fell in love with the tech behind cryptocurrencies when I read the whitepapers a couple of months ago. I invested in what I considered it had intrinsic value and, naturally, now I want to keep track of my money. is a great tool for that, but there’s a problem. CoinMarketCap Being a who also suffers of tabmania on Chrome, it’s almost impossible to properly keep in touch with my cryptos. Just take a look. It takes ages to look for the right tab. developer This is a decent number of tabs, usually there are many more That’s why I decided to kick off a simple but working for CoinMarketCap, as on a few searches on Google I only found poor, undocumented . desktop client attempts Incentive Simple enough, at the core of the app there is a webview which wraps the official website. At the moment, there are 4 advantages of using the desktop version: Running in its own window, it won’t get mixed up with your normal browsing Has its own special icon in the dock/ task bar/ alt+tab list/ cmd+tab list/ start menu You can set it to launch on startup When you have to quit the web browser because something made it go nuts and it started to use 1,000% CPU and 10 GB RAM, the client will continue to run (and the same goes for your ordinary browsing if it’s the client that’s causing the problem) Also, there are automatic updates, which is really important due to the fact there are some really cool features coming soon. Roadmap 🚀 Refresh button Automatic refresh Ability to set notifications when a specific price is hit Develop the same app for other coin tracking websites, such as CoinGecko Contribute The source code is, of course, open source and anyone can contribute. As I will be constrained by time, I encourage you to try and play with the project. _CoinMarketCap-Desktop — A simple desktop wrapper for CoinMarketCap_github.com PaulRBerg/CoinMarketCap-Desktop Build instructions are in the bottom of the README file. For feature requests and bug reports please or get in touch with me on or Twitter . submit an issue Gitter @PaulRBerg Download Below you can find download links for your favourite OS: (32 and 64 bits, Windows 7 and later) Windows (64 bits, Minimum 10.9) Mac OSX (Ubuntu 12.04, Fedora 21, Debian 8) Linux _A desktop wrapper for the official CoinMarketCap._coinmarketcapdesktop.com CoinMarketCap Desktop Support If you thing the app has true intrinsic value and it would help others, please consider sharing this article. Donations welcome. I will return your act of kindness tenfold by further developing and projects for the community. tools : 38fyAV4dReCog38JRA9UaoPfeh9RqrmhHQ Bitcoin Ethereum: 0x7deb85db0D84CFef5a5b9BDeb868Ac4cF269538d Litecoin: LQZ9LqqEiLjMK1DrTCdDKoRndVfpxF74Rt Thank you for reading. Here are some cookies for you! Looks delicious If you enjoyed this article, would you mind to clap it or share it? It’d be greatly appreciated ✌️ Find me on or if you want to chat. Twitter Keybase

Ethereum

Litecoin

I Developed a Desktop Client For CoinMarketCap

Take a closer look at the “Chinese Ethereum” , formerly called Antshares, has many features that make it superior to Ethereum, the second-generation blockchain platform that has garnered so much attention over the past two years. NEO Like Ethereum, NEO supports smart contracts, which allow for complex logic to be built into blockchain transactions. This means that payments, for instance, can be conditional upon some specific series of events occurring first. When the project launched as Antshares in August/September 2016, the focus was primarily on digital assets. It’s marketing was muddled and the coin price languished for nearly 9 months. Chart from Sep 2016 — April 2017 (from CoinMarketCap.com) Then a funny thing happened, in the spring of 2017 the project started to get its act together. It announced news of major cooperation with the Chinese government. It announced its rebranding to NEO. It started getting coverage in the English-speaking press. I honestly do not know who was behind the effort to redefine the project, but it was truly brilliant. Someone dubbed them the “Chinese Ethereum”, which attached them in spirit to the hottest blockchain in existence. China is a huge market, Ethereum is amazing. Put them both together and you’ve got the Reese’s Peanut Butter Cup of blockchain. But there is MUCH more to NEO than just marketing spin. Flexible Development Environment Unlike Ethereum, which forces software developers to learn and use its own proprietary language (Solidity), NEO supports many different programming languages, including Java, C#, VN.Net, F#, Kotlin, and Python, with plans to support C, C++, Golang, and Javascript in the future. NEO provides compilers and plug-ins for these languages, which are used to compile high-level languages ​​into instruction sets supported by NEO virtual machines. This makes the platform much more accessible to developers, allowing them to use programming languages that they are already familiar with. Ingenious Consensus Method / No Forks All blockchain platforms rely on consensus to prove that all transactions are valid. Bitcoin and many other projects (including Ethereum currently) use Proof of Work (PoW) methods, which basically require expending a lot of energy to solve complex mathematical problems. Another common method is Proof of Stake (PoS). With this method, blockchain nodes are required to “stake” or allocate funds (denominated in the currency being used) to earn verification rewards. The big benefit of PoS, compared to PoW, is that much less energy is expended. It is more eco-friendly. NEO utilizes a different consensus method called Delegated Byzantine Fault Tolerance (dBFT). You can read all about the mechanics of dBFD , but the biggest benefit of that system is that it prevents code splits/forks. This is a huge plus, as we have all seen the controversy and drama associated with the numerous Bitcoin (and Ethereum) forks. This will lead to greater stability of the NEO platform. here Transaction Speed Both Bitcoin and Ethereum suffer from slow (and expensive) transactions. Ethereum can handle about 15 transactions per second, while NEO can support over 10,000 transactions per second. When Cryptokitties became a thing recently, . Ethereum struggled to keep up with demand They look innocent, but they took down Ethereum. NEO is designed to handle mainstream apps like that as well and it is much better equipped for the future. To be fair to Ethereum, there are plans to improve performance in the future, but those plans are still not set in stone, with no near-term timeline for significant improvement. Quantum Computer Proof This one is really important. We are getting closer and closer to the time when quantum computers will be operational. And when they are, nearly every cryptocurrency will be vulnerable, because quantum computers may be able to break their cryptography. It’s important that every blockchain project is prepared as soon as possible for the future by using . quantum-resistant cryptography NEO already does. Dividends For NEO Holders NEO coins represent ownership in the NEO platform. There will be a maximum of 100 million NEO coins and these coins represent shares in its blockchain. NEO owners have voting rights for important decisions related to the platform. They also receive recurring dividends in the form of GAS coins. GAS is used to pay for NEO transactions and the dividends received by NEO holders are generated by those transaction fees. This is a unique, compelling model that incentivizes people to hold NEO. Note: if you own NEO, make sure you own the wallet and/or that you can claim the GAS that you are earning. For instance, most exchanges will not allow you to claim your earned GAS (Binance being a lone exception). I highly recommend the NEON wallet for NEO; it makes it very easy to see your current balances, in terms of NEO and GAS and to claim your GAS anytime you like. NEON Wallet in action. Platform For ICOs Ethereum has rightly gotten a lot of attention for its role in developing the booming ICO market in 2017. Hundreds of ICOs were deployed using Ethereum as the backbone for their tokens. The Ethereum ERC-20 token framework has been the biggest attraction for Ethereum overall and that standard is now accepted on nearly every exchange and most Ethereum-based wallets. But NEO also allows projects to launch their own tokens/projects on its platform. The is their ERC-20 equivalent. We’ve seen a couple of ICOs on NEO recently and now some templates/standards are popping up as well, such as the . NEP 5 token standard NEX ICO smart contract template You can expect a LOT more ICOs to running on NEO in 2018. Summary As you can see, NEO has many powerful features not found in other blockchain projects and the combination of those features, with its smart contract capabilities, make it an attractive platform for future dApps. The world has definitely taken notice, as the price has skyrocket from US$0.20 on April 1, 2017 to nearly $80 at the close of 2017. With a market capitalization of around US$5 billion, however, it still represents a tremendous value, when you consider that Ethereum has a market cap of $70 billion. NEO from April 2017 to Dec 31, 2017 (per CoinMarketCap.com) While this is by no means investment advice, I am extremely bullish on NEO. (In full disclosure, I also own some NEO, as well.) It’s future-proof, thoughtfully-designed, and fully focused on being the hub of the next-generation smart economy. Please consider supporting the new project I am working on, Narrative . Our goal with Narrative is to create the world’s first true content economy, giving users autonomy over the content they create. 85% of all revenue generated by the Narrative Network is returned to its members. Narrative White Paper: https://assets.narrative.network/documents/narrative-network.pdf Narrative Token Sale: https://tokensale.narrative.network

Binance

fees

Why the future may already be here with NEO

Brought to you by . AngelLoop “Making money is an incidental consequence of having strong relationships.” Think about that for a minute. It should help you overcome some of the barriers that you may have put up when delaying building new or improving your current ones. relationships As entrepreneurs we have a tendency to focus on product, market, profit. All of these tenants are important, however they are all derivatives of the relationships we build and nurture along the way. First let’s give some love to Ray: The Ray I speak of is none other than Ray Dalio, the Principal and CEO of Bridgewater Associates — the world’s largest hedge fund. He helped me rediscover this notion in his latest book called the “Principles: Life and Work”. Ray argues that we should assign relative value to things that we want (including money, work, and relationships) and weigh them properly. He sets a higher value to over money because “money” was less meaningful since it is a derivative of the two, i.e. the relationships you build will help you achieve meaningful work and working with them will help you build your . work and meaningful relationships wealth Startups that raised money from investors, let me explain. After knowing your investor for a few short weeks before s/he cuts you a check, you have to understand that you are signing up for, at least, a ten year commitment or something akin to a marriage. Your investor/s have a ton of value to add besides the money that they fund you with and whats more important to acknowledge is that they have a vested interest in your success. You’ve know an investor for a few weeks before they wrote you out a check, you will be married to them for ten years. The values that investors bring to the table. [1] Advice and feedback— Skip a few challenges and ask your investors how they’ve overcome them in their own career. Either they have experienced what your going through before or have seen similar challenges that their other portfolio companies have overcome and will share that with you as a common curtesy. All you have to do is ask for help. [2] The network effect — Your investors have cultivated a big network over their long career and can introduce you to clients, key hires, other CEO’s they’ve backed and when you are ready to new investors. [3] They are your evangelists — People talk and brag and your investors are no different. They are a great lead gen for your business and want to share your trials and tribulations with their network. Strong relationships help you create more wealth How do you build a strong relationship with your investors and increase your companies valuation. [1] Keep them in the (link to an investor template) — In other words keep them updated on your startups progress. For early stage companies, once per month should do it and companies that are a little older, quarterly updates and a few phone calls will make all the difference. loop [2] Ask them for help — This can be around intros to folks in their network, around challenges you are experiencing and reviewing some of the materials you are about to publish. They love being engaged and telling them that everything is peachy is not something that will peak their interest. [3] Lastly, you want to reward them. The way you do that is include a kudos section in your investor update. They love having other investors in your cap table seeing how helpful they’ve been to you because they, too, are trying to get credit from other investors on your cap table. To leave you with something that really inspires me to continue to writing these posts, here’s old Teddy with some truth bombs. I’ve been in the startup game for the last 15 years and I know how investors digest information and how founders lag in providing it. We’ve built a bridge for founders and their stakeholders at because succeeding in your business means being able to build meaningful relationships with people that have a vested interest in your success. Don’t be a {enter derogatory term here} and instead be pro-active with your stakeholders because they will return the favor. It’s a way to stress test your thinking and increases your odds of making the best decision possible. AngelLoop That’s all from me for now, check out our other posts or follow us on the Socials. I love you, Igor @ AngelLoop P.S. Why is 2018 the best year to fundraise for your company? Like the article? Receive ’s latest posts in your inbox — Subscribe ! AngelLoop here , our weekly sponsor, is the communication and collaboration tool for founders to improve transparency with their stakeholders and save time on their investor updates. AngelLoop Track, share and leverage today.

Different

Turn your relationships into wealth. Here’s how.

Write a fast and modern mini todo application using Iris MVC and Vue.js Vue.js is a front-end framework for building web applications using javascript. It has a blazing fast Virtual DOM renderer. Iris is a back-end framework for building web applications using The Go Programming Language (disclaimer: author here). It’s one of the fastest and featured web frameworks out there. We wanna use this to serve our “todo service”. The Tools Programming Languages are just tools for us, but we need a safe, fast and “cross-platform” programming language to power our service. is a open source programming language designed for building simple, fast, and reliable software. Take a look which great companies use Go to power their services. Go rapidly growing here Install the Go Programming Language Maybe or user? Windows Mac OS X The article does not contain an introduction to the language itself, if you’re a newcomer I recommend you to bookmark this article, the language’s fundamentals and come back later on. learn The Dependencies Many articles have been written, in the past, that lead developers not to use a web framework because they are useless and “bad”. I have to tell you that there is no such thing, it always depends on the (web) framework that you’re going to use. At production environment, we don’t have the time or the experience to code everything that we wanna use in the applications, and if we could are we sure that we can do better and safely than others? In short term: Good frameworks are helpful tools for any developer, company or startup and “bad” frameworks are waste of time, crystal clear. You’ll need two dependencies: Vue.js, for our client-side requirements. Download it from , latest v2. here The Iris Web Framework, for our server-side requirements. Can be found , latest v10. here If you have Go already installed then just execute to install the Iris Web Framework. go get -u github.com/kataras/iris Start If we are all in the same page, it’s time to learn how we can create a live todo application that will be easy to deploy and extend even more! We’re going to use a vue.js todo application which uses browser’s local storage and doesn’t have any user-specified features like live sync between browser’s tabs, you can find the original version inside the vue’s . docs web/public/js/app.js web/public/index.html todo/item.go todo/service.go web/controllers/todo_controller.go web/main.go Read the comments in the source code, they may be very helpful The client-side (vue.js) Let’s add our view, the html. The server-side (iris) Our view model. Our service. We are going to use some of the MVC functionalities of the iris web framework here but you can do the same with the standard API as well. And finally our main application’s endpoind. Run the Iris web server you’ve just created by executing from your current path (%GOPATH%/src/%your_folder%/web/). go run main.go $ go run main.goNow listening on: Application Started. Press CTRL+C to shut down._ http://localhost:8080 Open one or more browser tabs at: and have fun! http://localhost:8080 Download the Source Code The whole project, all the files you saw in this article are located at: https://github.com/kataras/iris/tree/master/_examples/tutorial/vuejs-todo-mvc References (using browser’s local storage) https://vuejs.org/v2/examples/todomvc.html (mvc examples and features overview repository) https://github.com/kataras/iris/tree/master/_examples/mvc Thank you, once again Happy new year and thank you for your pattience, once again:) Don’t hesitate to post any questions and provide feedback(I’m very active dev therefore you will be heard here!) Don’t forget to check out my medium profile and twitter as well, I’m posting some (useful) stuff there too:) https://medium.com/@kataras https://twitter.com/MakisMaropoulos

A Todo MVC Application using Iris and Vue.js

When shut down in early 2017, it forced many people to race to find a suitable replacement. That’s because the automation tool had become invaluable part of how they engaged with their Instagram audience. Without it, their followings had simply stopped growing. Instagress This article was originally written a year ago. I’ve decided to update it to keep it current with the latest developments in Instagram automation. The list below contains what I think are the five best Instagress alternatives as of 2019. 1. SocialCaptain SocialCaptain is top-of-the-line when it comes to Instagram automation. Its systems are driven by advanced AI modules, which help it self-optimize and improve its performance the longer it runs. It’s like having a personal Instagram assistant that constantly gets better at its job. The service also comes with an assortment of audience targeting filters, live analytics, exportable growth reports, dedicated customer support, an unlimited amount of actions per day, and many more unique features. 2. Instajool Instajool is one of the few platforms with support for every browser and mobile device out there right now. This makes it exceptionally accessible, as well as completely safe given that it doesn’t require you to download any extra software. Depending on the plan that you choose, you can manage anywhere from ten to a hundred Instagram accounts in one place. Instajool also has a scheduler for planning out certain times when you want the tool to be active. 3. FollowingLike FollowingLike is quite a versatile tool, as it provides automation options for a wide variety of social networks. In addition to Instagram, it can also handle your activity on Facebook, Google+, Linkedin, Pinterest, Reddit, and Tumblr. One aspect that sets FollowingLike apart from the rest is its payment options. Rather than only offer subscription-based plans like most services, you can pay a one-time fee and never have to worry again. 4. Influuu Influuu assists you by pairing you with a team of marketing experts. All you need to do is fill out a short form with the names of other Instagram influencers in your field, and then a little more information about yourself or your business. From there the professionals will take care of the rest. Their marketers take the greatest care in studying your account, so that they can individualize their approach based on your needs and get you the most followers possible. 5. Instazood Instazood allows you to customize your features as you’d like. They have four modules to choose from: an Instagram bot with basic automation, a comment tracker/organizer, a direct messenger, and a post manager. Being able to pay for each module separately, and cut out the ones you don’t need, makes Instazood a very affordable alternative.

5 Helpful Instagram Growth Tools (to Replace Instagress)

Demons in Digital Gold, Part 1 If you have not already done so, please read to this series. the introduction A derivative is security with a price that is dependent upon or derived from an underlying asset. The derivative itself is a contract between two parties based upon the asset. Its value is determined by fluctuations in the underlying asset. The most notorious derivatives were the primary cause of the 2008 great financial crisis. — Financial Times The Times 03/Jan/2009 Chancellor on brink of second bailout for banks — Message embedded in the Bitcoin Genesis Block by Satoshi Nakamoto This detail, “second bailout for banks,” suggests that rescuing banks [from reckless investments in financial derivatives] was a problem for Satoshi. It is seen as one of his motivations for developing Bitcoin. — Bloomberg Summarizing the quote-a-thon: financial derivatives can be dangerous and lead to ruin on an individual or MUCH larger scale. When a party cannot meet their contractual obligations, bad things can happen. Combining “much larger scale” with widespread failure to “fulfill their obligations” and TREMENDOUSLY “bad things can happen.” A derivative is a contract between parties that must TRUST each other to fulfill their obligations. Fair to say that Satoshi loathed financial derivatives, and Bitcoin was developed as an anti-derivative. TRUSTLESS. DECENTRALIZED. SECURE. Stone tablets Those three properties certainly make it onto the stone tablet of Bitcoin’s customer-perceived value proposition. (Quotes in the bullets below are taken directly from the original whitepaper.) the system is entirely self-enforcing, so parties do not have to trust each other — or even know each other — to transact. “What is needed is a system based on cryptographic proof instead of trust.” Trustless: the system is peer-to-peer, and eliminates the need for “financial institutions serving as trusted third parties.” Decentralized: the system absolutely assures transactions between parties. Confirmed transactions are “completely non-reversible.” Secure: Before continuing, let’s address perspective as discussed in to this series (that you’ve already read). the introduction This series focuses on the present perspective, because we live here. So far, I’ve spilled quite some ink on the past perspective. That’s copacetic: these were not only foundational elements serving as key motivations and objectives in 2009, In other words, we are firmly in the present perspective. these remain core elements that define Bitcoin (et al) in the eyes of today’s cryptocurrency users. Bitcoin you’re HODLing “What does all this have to do with my Bitcoin?” you may be thinking, and justifiably so. I am working from the assumption that you hold Bitcoin for one or more reasons, and hopefully not STRICTLY because the price goes up. Your reasons have to do what makes Bitcoin different, and most all of those differences are rooted in the three “stone tablet” properties. Speaking for myself, I consider them THE BIG THREE: these are the properties that initially attracted my attention, then piqued my curiosity, then drove me to learn about technology down to “the bare metal,” and built my enormous respect for what Bitcoin (et al) has accomplished and represents. Hell, I was inspired enough to . blockchain write a book I’m betting we agree that these are key properties that help define Bitcoin’s value. TRUSTLESS. DECENTRALIZED. SECURE. I’m betting we agree that these are key reasons that we own Bitcoin. May be a derivative “Major dissonance!” you contend. “You used the term ANTI-derivative. How the hell could my Bitcoin be a derivative?” I feel you, the dots do not seem to connect. At long last, a thousand words into this post, I am gonna’ get down to dot connecting. I’m here to lay out facts that you may have overlooked. You’re here to reach your own conclusions. Y’all being a sophisticated readership, many of you hold Bitcoin (et al) on your own private wallet. Some of you hold your Bitcoin on an exchange, and I’ve got news for you: you don’t own Bitcoin, you own a bitcoin derivative. [Those of you with your own private wallets need to keep reading, as this also impacts you in a BIG WAY, albeit indirectly.] This is NOT a matter of definitions/nomenclature. While the explanation that follows is not technical, curious readers may want to consult This cuts straight to the matter of what makes a Bitcoin a Bitcoin. Your Bitcoin (et al) on an exchange does not pass the test. Where is a Bitcoin? What’s in YOUR wallet? Bitcoin held in your own private wallet — Mac/Windows/Linux/mobile app, full node, Trezor, etcetera — includes the PRIVATE key of each bitcoin address you own. That private key enables your wallet to construct and submit transactions to the bitcoin network, transactions that SPEND your Bitcoin. Let’s quickly evaluate The Big Three … check. You transact with other entities across the bitcoin network with complete certainty, with absolutely no implicit trust. Trustless: check, as long as you pass . You interact directly with the bitcoin network, peer-to-peer, not relying on ANY intermediary. Decentralized: Our Bitcoin wallet checklist check, ditto passing the checklist. Your wallet performs its own cryptography, generating its own digital signatures when sending Bitcoin and verifying applicable data when receiving Bitcoin. Another facet here is cyber-security — keeping your private keys, well, private — and that element (for example, proper anti-malware and backup) is up to you. Secure: Holistically, this is the promise to “be your own bank” fully realized. What’s on your exchange? “Aren’t you nitpicking?” you ask. “Holding Bitcoin (et al) on an exchange just means that the exchange manages my wallet, right?” WRONG. “But right there on the home page it says ‘My Wallet’ and lists my balances by coin!” What you see is simply your account balances tracked by an internal database maintained by the exchange. On an exchange, you DO NOT HAVE a bitcoin wallet, full stop. **Let’s unspool this**You open and fund an account on an exchange. You purchase Bitcoin on the exchange. The exchange records that purchase in their own internal database. You cannot see the private key corresponding to your Bitcoin purchase. You cannot even see the public key corresponding to your Bitcoin purchase. In fact, THERE IS NO private-public key pair corresponding to your Bitcoin purchase, and furthermore, your purchase IS NOT RECORDED on the bitcoin blockchain. “Say WHAT?!” Re-read the above paragraph and refer to as needed. Before evaluating The Big Three, let’s see what IS on an exchange. Where is a Bitcoin? Your exchange DOES own Bitcoin (et al). Your exchange holds its Bitcoin in a real wallet with a private-public key pair for each address the exchange owns. In other words, your exchange holds an amount of Bitcoin in its wallet equal to the grand total of all bitcoin holdings of all users as recorded in their own internal database. In theory, every exchange keeps a full reserve of each cryptocurrency they own. An exchange expands its reserve by purchasing Bitcoin from another exchange, or when a user transfers (“deposits”) externally held Bitcoin onto the exchange. An exchange reduces its reserve by selling Bitcoin to another exchange, or when a user transfers (“withdraws”) Bitcoin off the exchange. If you routinely review your exchange’s published audits, you’re probably quite comfortable that your exchange is fully backed. If you are confident that your exchange is routinely audited by a reputable third-party, you’re probably pretty comfortable. Do a little homework and you’ll sleep easier. The “in theory” qualifier two paragraphs above may or may not make you uncomfortable. So you’ve done your homework and are secure in the knowledge that your exchange holds a full reserve of Bitcoin. Your account is a balance recorded in their own internal database. Recognize that you DO NOT own any Bitcoin at any specific address. You literally own a bitcoin derivative: an entry in their internal database, representing a tiny fraction of the underlying asset that is the exchange’s reserve of Bitcoin held in its wallet. **Let’s continue to unspool this by selling some of your Bitcoin**Your sell order is matched against buy orders in the exchange’s dark pool. The match — your sell order and one or more buy orders — is settled entirely within the exchange. Your bitcoin balance is reduced reflecting your sell, and some other user(s) bitcoin balance is increased reflecting their buy. Fiat currency balances are adjusted accordingly for you and the other user(s). Now let’s look at what DOES NOT happen in this trade. The exchange’s reserve of Bitcoin does not change. The private-public key pairs in the exchange’s wallet do not change. The only time your activity is recorded to the blockchain is a transfer off the exchange, for example, to your own private wallet. NO TRANSACTION is recorded on the bitcoin blockchain. By now you have an inkling of what evaluating The Big Three will yield … NO. You depend on your exchange and trust them implicitly. Trustless: NO. All of your activities — and the activities of your fellow users — strictly run through the exchange. Decentralized: check, with caveats. A top-notch, reputable exchange is secure on a transaction basis. Such an exchange should also be secure on a cyber-security basis, with low risk that your Bitcoin will be lost. This shouldn’t be a surprise, because successfully hacking an exchange is extremely profitable and VERY difficult to catch. Every one of the major exchanges has a ginormous target painted on their back. Secure: You in an awkward position, nevertheless, as significant hacks with significant losses regularly make headlines. That is such a great question, I will tackle it in two sections. “So I hold a bitcoin derivative,” you acknowledge. “Why should I care?” Bitcoin derivatives: your own holdings Recognizing that on an exchange you hold bitcoin derivatives — as opposed to “Bitcoin proper” — is the first step. If you bought Bitcoin (et al) because you feel strongly about The Big Three, your next step is adjusting your thinking, planning, and actions. I wrote about the pros and cons of on an exchange, complete with actionable mitigations. Check out that post. Keeping your cryptocurrencies **Know thy exchange**One key takeaway from the section above: you are placing A LOT of trust in your exchange. No FDIC insurance. No zero-liability credit card protection. No “contact us” (it’s hard enough to get a reply out of an exchange in the best of times). And most pertinent to our dialog, none of the “be your own bank” dynamic that many of us hold so dear. If something happens to your exchange — through hacking, malfeasance, or plain bad luck — you will be in a world of pain. In short, you could be SOL. So do your homework. Read the terms and conditions. Read reviews from reputable (that would exclude Reddit) sources. You might decide that a different exchange is more trustworthy and/or secure than your own. If you are wedded to keeping your Bitcoin (et al) on an exchange … there is a concrete measure you can take to mitigate risks of your exchange being hacked: . spread your cryptocurrency holding across multiple exchanges … technically speaking, that spreads but does not reduce your risk. **Consider using your own private wallet**There are many options here: an app on your Mac/PC, an app on your mobile, running a full node, and a hardware wallet. Read my earlier series for an overview of these options. Yes, you can “be your own bank!” Where can I keep my Bitcoin? With that said, a note of caution from is in order … The Bitcoin Tutorial Throughout , we’ve discussed the contemporary cryptography that protects Bitcoin. Should you end up on the wrong side of all that cryptography, there isn’t a person on the planet who can help you. If misused, however, every bitcoin wallet has the potential to LOSE all of your bitcoin. The Bitcoin Tutorial It is unbreakable. If you are not comfortable with a wallet you’re considering, find another wallet. Please RTFM. **One last reality check**Transferring Bitcoin (specifically BTC) has become more challenging and expensive in the past months. This is not much of an issue if you are HODLing Bitcoin, as you will not make frequent transfers to and fro. If you want to trade your Bitcoin (specifically) at the drop of a pin, however, you need to be aware of the transaction traffic jam that is the bitcoin mempool. [Lest you wonder, yes, an upcoming post in this series will dissect said traffic jam in detail.] Bitcoin derivatives: the macro picture Hey! You with your own private wallet! This is the where I describe how … this also impacts you in a BIG WAY, albeit indirectly. ... thanks for rejoining the class. There are many reasons why ALL cryptocurrency owners should be concerned about bitcoin derivatives. **The adoption bullshit**First, recognize that the VAST majority of bitcoin (et al) owners keep their holdings on an exchange. When you read about soaring “adoption” rates, those new users are opening an account on an exchange. As spooled out above, such “adoption” has NOTHING to do with the bitcoin ecosystem. Headlines proclaiming “Mass Adoption of Bitcoin!” are bullshit. Are more and more real people transacting commerce in Bitcoin? Quite the opposite, as the aforementioned Bitcoin traffic jam REDUCED the number of businesses and people transacting in Bitcoin in 2017. That would be fabulous news, but you would be quite wrong to reach such a conclusion. **The price discovery distortion**Next, consider a properly functioning price discovery mechanism that reflects the customer-perceived value of a cryptocurrency. Yes, I know, this exercise requires temporary suspension of disbelief … we can at least PRETEND to be value investors driven by fundamentals. Sense of scale: the number of trades of Bitcoin (specifically BTC) on exchanges EACH DAY is greater than the number of transactions recorded on the bitcoin blockchain IN A MONTH. [Ratio extrapolated using data for the last quarter of 2017.] In other words, “bitcoin activity” is dominated by trading that has NOTHING to do with the bitcoin ecosystem. If you’re a speculative trader, you’re totally cool with that. Let me drive that point home with … If you’re fundamentals-driven investor, you must recognize that the price discovery mechanism has little if anything to do with any underlying value. **A creative thought experiment**Finally, imagine that the entire bitcoin ecosystem suddenly goes “poof” and we find ourselves with no miners, no peer-to-peer network, no blockchain. Nope. We’re in the world of make-believe here, so work with me. Everyone trading on the exchanges goes on merrily trading on the exchanges (other than a tiny number of souls unable to transfer Bitcoin to/from their private wallets). Ask yourself: is the disappearance reflected in the hulking bulk of trading activity? I am not working a philosophical “if a tree falls in a forest” exercise with you. I am playfully illustrating that the VAST amount of cryptocurrency activity has precious little to do with the underlying blockchain, much less customer-perceived value of the cryptocurrencies. at least a dozen circa 2013 cryptocurrencies — each built atop the bitcoin code base with their own blockchain ecosystems— continue to trade today on exchanges, Sotto voce: despite the fact that their respective blockchains have long since gone completely dark. Long-time Bitcoin bull and top-flight FinTwit contributor Brent Johnson ( ) recently opined thusly: @ SantiagoAuFund Bitcoin as described in Satoshi’s whitepaper is a marvelous & revolutionary invention. But from what I can see, it is being used very little as Satoshi intended. Once again, I remind you that the of this series is for you to assimilate facts and reach your own conclusion. Neither Brent nor I are throwing the bitcoin baby out with the blockchain bathwater. raison d’etre We believe Bitcoin holds value, and we strongly believe everyone needs to evaluate its value with the latest facts in mind. Future perfect tense? “But what about SegWit and Bitcoin Cash?” you ask. “Won’t they ‘fix’ the derivatives conundrum and make this issue moot?” In a word, NO. Yes, SegWit increases Bitcoin’s (specifically BTC) transaction throughput by as much as 5x. Yes, Bitcoin Cash increases its transaction throughput by as much as 8x compared to pre-SegWit BTC. And neither improvement changes the 1+ hour latency needed to fully confirm a transaction on their respective blockchains. Those are both laudable and useful improvements, though hardly of the scale needed to close the gap with trading activity. Furthermore, exchanges are struggling — to say the least — to support trading activity within their independent closed systems. They have ZERO interest in adding complexity, as would be required for a fully blockchain interwoven system. Even granting a miracle would not “fix” the derivatives conundrum. A suitable could reveal your PUBLIC keys, but the exchange can never hand you the corresponding PRIVATE keys; that would open the Pandora's Box of an entity yanking the bitcoin carpet out from underneath the exchange, with no way to determine if the entity was you or any random ne’er-do-well. deus ex machina Can’t we get a simple Thomas Cook? Way back when I first heard the term “cryptocurrency exchange,” I had a mental image of a simple Thomas Cook exchange. Ya’ know, the airport booth where you exchange “your” fiat currency for local fiat currency. This is entirely workable … Your private wallet app generates a new private-public key pair Your wallet calculates a Bitcoin address from the public key You include that address with the fiat currency transfer to the exchange The exchange sends Bitcoin (et al) to the address you provided Your private wallet acknowledges receipt of the expected Bitcoin … indeed, the above is EXACTLY how some bitcoin ATMs operate! So why don’t cryptocurrency exchanges work that way? Hell, we haven’t even mentioned MARGIN extended by most of the major exchanges. These highly profitable aspects of running an exchange are NOT compatible with the vision of a fully blockchain interwoven system. They are maximized by a closed system trading within the exchange’s dark pool. Simple: there isn’t much money in it. There is way, WAY more money to be made off spreads and fees in crazy-high-volume crypto-currency trading. I leave this post with a word-association exercise … derivatives dubious price discovery exchange dark pools (a.k.a. “ponds” of liquidity) margin (a.k.a. leverage) … see if that rings any bells. Next in the series … Do exchanges pose a systemic risk? Follow me @ Pressed250 on Twitter Copyright © 2018 Bruce Kleinman. All Rights Reserved.

Solana

Bitcoin Cash

Zcash

Dash

Discovery

Bitcoin you’re hodling may be a derivative

We have a fairly standard setup, a primary node and a whole bunch of secondaries that most of the job steps get farmed out to. Jenkins These secondary nodes sit doing nothing overnight so we thought it would be a good idea to scale them down in the evening and then back up in the morning so we can use the money we’ve saved to run more secondaries during the day when they’re in demand. We run various jobs on our Jenkins infrastructure but the most common job is for building and testing our monolith on every push to a PR and merge into master. This basically involves doing a git checkout of the branch (into existing workspaces on the primary node so we don’t have to do a full initial checkout), building a image that contains all of the dependencies and the version of the codebase at the time the job was ran and then running the tests inside the resulting container (on any of our secondary nodes so we can run lots of jobs in parallel, files are transferred between nodes using Jenkins stashes). Docker Building this Docker image from scratch takes around 10 minutes and we rely on the Docker image cache on these nodes to reduce our build times by placing the step which normally invalidates the cache (the copy’ing of the updated codebase) at the end of the Dockerfile. The Dockerfile looks something like: FROM ubuntu:14.04 # Things like apt-get installs, these take a decent amount of time<some bash commands> # These live in our main codebase along side the code and basically never change<copy in some config files> # There's a fair few of these, they take a while but rarely change<copy some requirements.txt files><some pip installs> # This is where we expect the cache to be invalidated and copy'ing in the files doesn't take long<copy in the version of the codebase that's being built> So if we want to autoscale our secondary nodes we need to make sure that they have the image cache before jobs start running. Attempt #1 was to simply pull down a copy of the image from our registry in the Cloudformation userdata when the node comes up. This failed because Docker wont use images pulled from a registry as part of the build cache. This is considered a feature — https://github.com/moby/moby/issues/20316 Attempt #2 was to replace pulling the Docker image, with cloning of our repository into and then building the Docker image from that version of the codebase when the node first comes up. This would give us a copy of the Docker image from a recent version of the codebase along with the build cache we needed to speed up subsequent builds. /tmp This failed, during the first run of the Jenkins job the cache was invalidated at the first step when we copy over the config files even though the contents of them hadn’t changed. COPY This was slightly confusing because I thought that Docker only invalidated the cache at a line if the file had changed and it hadn’t. Some digging around revealed that Docker also uses the value on a file when considering if it has changed or not. COPY mtime https://github.com/moby/moby/issues/4351#issuecomment-76222745 So what was happening was that the git checkout of the codebase in the Jenkins job created files with different to that of the files from our checkout of the codebase into at node creation time and so Docker considered the config files we copy in early on to be changed and invalidated the cache earlier than we wanted. mtimes /tmp We didn’t see this issue before as we do the git checkout part of the job on our primary node into workspaces which are never deleted and so after an initial checkout these files are never touched and Docker never considers the early steps to have been invalidated. COPY We can replicate this behaviour with a simple example: We have a project with two files a Dockerfile and a text file vagrant@vagrant-ubuntu-trusty-64:~$ lsDockerfile  test The Dockerfile just copies in our file vagrant@vagrant-ubuntu-trusty-64:~$ cat Dockerfilefrom ubuntu:16.04COPY test /srv/test And lets take a note of the of our test file for later on mtime vagrant@vagrant-ubuntu-trusty-64:~$ stat testFile: ‘test’Size: 0          Blocks: 0          IO Block: 4096   regular empty fileDevice: 801h/2049d Inode: 140134      Links: 1Access: (0664/-rw-rw-r--)  Uid: ( 1000/ vagrant)   Gid: ( 1000/ vagrant)Access: 2017-12-31 18:03:33.995881878 +0000Modify: 2017-12-31 18:03:33.995881878 +0000Change: 2017-12-31 18:03:33.995881878 +0000Birth: - Finally if we build it vagrant@vagrant-ubuntu-trusty-64:~$ sudo docker build .Sending build context to Docker daemon 13.82 kBSending build context to Docker daemonStep 0 : FROM ubuntu:16.0416.04: Pulling from ubuntuStep 1 : COPY test /srv/test---> 3be8d8c094bf We don’t have that step cached and so Docker just runs it. If we modify test vagrant@vagrant-ubuntu-trusty-64:~$ echo 'hello' > testvagrant@vagrant-ubuntu-trusty-64:~$ sudo docker build .Sending build context to Docker daemon 14.34 kBSending build context to Docker daemonStep 0 : FROM ubuntu:16.04---> c1ea3b5d13ddStep 1 : COPY test /srv/test---> 75bb69e528c3Removing intermediate container 6771d1e1f191Successfully built 75bb69e528c3 Docker picks up the change and invalidates the cache layer, nothing surprising here. Now what if came from a git repo ? test I bundled these two files into a git repo, pushed them up then pulled the repo down to a seperate folder vagrant@vagrant-ubuntu-trusty-64:~$ mkdir gitvagrant@vagrant-ubuntu-trusty-64:~$ cd git/vagrant@vagrant-ubuntu-trusty-64:~/git$ git pull :AaronKalair/test.git git@github.com And does Docker use the cache we created with the earlier for the file? docker build vagrant@vagrant-ubuntu-trusty-64:~/git/test$ sudo docker build .Sending build context to Docker daemon 47.62 kBSending build context to Docker daemonStep 0 : FROM ubuntu:16.04---> c1ea3b5d13ddStep 1 : COPY test /srv/test---> f4fe0a287838Removing intermediate container 20c77a3dee81Successfully built f4fe0a287838 Nope! Are the files identical? The one from the git clone vagrant@vagrant-ubuntu-trusty-64:~/git/test$ md5sum testa10edbbb8f28f8e98ee6b649ea2556f4  test The original vagrant@vagrant-ubuntu-trusty-64:~$ md5sum testa10edbbb8f28f8e98ee6b649ea2556f4  test Yep, there identical. What about the ? mtime vagrant@vagrant-ubuntu-trusty-64:~/git/test$ stat testFile: ‘test’Size: 7          Blocks: 8          IO Block: 4096   regular fileDevice: 801h/2049d Inode: 262341      Links: 1Access: (0775/-rwxrwxr-x)  Uid: ( 1000/ vagrant)   Gid: ( 1000/ vagrant)Access: 2017-12-31 19:37:05.348272796 +0000Modify: 2017-12-31 19:37:05.348272796 +0000Change: 2017-12-31 19:37:05.348272796 +0000Birth: - Nope its changed (it was originally), the git pull sets the modified, access and change time to the time of the clone. 18:03 What about existing files does a git pull affect those? If we add another file to the project push it up … vagrant@vagrant-ubuntu-trusty-64:~$ touch test_testvagrant@vagrant-ubuntu-trusty-64:~$ git add test_testvagrant@vagrant-ubuntu-trusty-64:~$ git commitvagrant@vagrant-ubuntu-trusty-64:~$ git push origin master and then pull it back down into the other git checkout … vagrant@vagrant-ubuntu-trusty-64:~$ cd git/test/vagrant@vagrant-ubuntu-trusty-64:~/git/test$ git pull vagrant@vagrant-ubuntu-trusty-64:~/git/test$ stat testFile: ‘test’Size: 7          Blocks: 8          IO Block: 4096   regular fileDevice: 801h/2049d Inode: 262341      Links: 1Access: (0775/-rwxrwxr-x)  Uid: ( 1000/ vagrant)   Gid: ( 1000/ vagrant)Access: 2017-12-31 19:40:05.032278718 +0000Modify: 2017-12-31 19:37:05.348272796 +0000Change: 2017-12-31 19:37:05.348272796 +0000Birth: - vagrant@vagrant-ubuntu-trusty-64:~/git/test$ stat test_testFile: ‘test_test’Size: 0          Blocks: 0          IO Block: 4096   regular empty fileDevice: 801h/2049d Inode: 262359      Links: 1Access: (0664/-rw-rw-r--)  Uid: ( 1000/ vagrant)   Gid: ( 1000/ vagrant)Access: 2017-12-31 20:36:22.916378925 +0000Modify: 2017-12-31 20:36:22.916378925 +0000Change: 2017-12-31 20:36:22.916378925 +0000Birth: - The existing test file is untouched and the new file appears with all the timestamps set to the time of the git pull Ok so that explains the behaviour we’re seeing and why we’ve never had this problem before but we still can’t autoscale our secondary Jenkins nodes without fixing the caching issue. So attempt #3 that turned out to be successful was to: Create a base image that we use in at the start of the main Dockerfile which already has ran the expensive steps and have that pulled down to the nodes when they spin up. FROM This would then effectively replicate having the expensive steps in the build cache. So we have a nightly build from a Dockerfile that looks like: # NIGHTLY IMAGE FROM ubuntu:14.04 <some bash commands><copy in some config files><copy some requirements.txt files><some pip installs> With our Jenkins job now using a Dockerfile that looks like: FROM NIGHTLY_IMAGE <copy in some config files><copy some requirements.txt files><some pip installs><copy in the version of the codebase that's being built> Now all the expensive commands that we wanted cached (initial bash commands and pip installs) are in the nightly image which we pull to an instance when its created and Jenkins uses it in the line. FROM The repeated in the Dockerfile Jenkins uses for the job ensures that if the requirements change before the next nightly build those changes are reflected in the built image. pip installs If the nightly image build uses versions of the files with different then it doesn’t matter as a with the requirements already there only takes a few seconds. mtimes pip install The nightly image is built as a Jenkins job every night at 2am and cron jobs on the sidekicks as well as autoscaling operations ensure they have the latest nightly image every day. And there we have it, we now spend less money and have more Jenkins capacity during the day when we need it! Follow me on Twitter @AaronKalair

BUNCH

Working with the Docker build cache to autoscale our Jenkins nodes

Yes, I know it is very enticing to chose a Free VPN over a Paid one. I myself have a habit of looking for ways to get out of paying for Online Services as well. However this is one thing you don’t want to skimp on. The reason being is that you need to be able to trust your VPN Provider. When you use a free service there is no value in trust between you. Essentially when you pay for a VPN Service you aren't buying the underlying of Servers and their encryption. You are buying their trust that they will keep all of your information private and safe. network So what is the difference? Why should I pay for something that some offer for free? Well like I said, the big number one reason is you have no way of trusting them. While there are legitimate Free VPN Providers out there. You could easily be downloading a virus or connecting to a malicious VPN of some sort. Most Free VPN Providers will usually log your Internet Usage. Such as what sites you visit and what you do while you’re on those sites. However there are some that will even sell your personal Information on the black market such as email address, name, telephone number, credit card, etc.. pretty much anything that you do on the Internet is up for grabs. Another bad quality of these Free VPN Providers is that they will push ad’s onto the sites you visit. While this on it’s own isn't a terrible thing to most people. The big problem with this is you can’t trust most of the ad’s they push. The reason being is a common trait among free services online is they will use pay per view ad services. These services are the same that Hackers will typically use to push out viruses. So, while the VPN might be protecting you and doing it’s job. The Ad’s that they give you might be harmful to your computer. Remember we want a VPN Provider for Privacy and means and you simply can’t assure you will have that with a Free Service. While I myself like to find free ways of getting stuff. I personally recommend paying for a VPN Service and Highly advise against using a free one. Simply because there is no way of knowing what you will be getting. Security View Original Story Recommended Articles Why You Should Never Trust A Domain Name!! An Article teaching you about how Hackers can use Website URL’s and Domain Names to steal your information and how you can protect against it. WiFi Gone Rouge An article explaining how Hackers can use WiFi Networks in order to steal your personal information and how you can protect against it. Internet Security In The Modern Age an article on VPN’s and other Anonymity features how they work and how you can use them to protect you internet Privacy and Security. My VPN Review Notes All of the notes that I tool down while auditing all the Different VPN Companies out there. You can use this article to base your questions off of when you start searching or to choose the VPN Provider that fits you best. Recommended VPN Providers Private Internet Access Nord Virtual Private Network (TOR Functionality) StrongVPN

Paid

Why You Should Stay Away From Free VPN Providers

Everyone seems ecstatic about Bitcoin right now, and for a while I’ve been interested in writing about — the cool frontend tool for building analytical applications. The reason I like Dash is it allows me to remain in my comfort zone: Python. And it boasts of being lightweight, easily customizable, you know, all those good things. Dash by plotly are a pretty useful indicator in stock trading. It’s still a as to whether Bitcoin is like a stock. As such, I’m using the term loosely here. help identify trends, provide trade signals, and smooth out price action by filtering out the “noise” from random price fluctuations. There are various variants of, and ways to calculate moving averages. Simple Moving Average is simply the average of the last values with being the period to average over. Weighted Moving Average and Exponential Moving Average are less simple in that they introduce weights and also take into consideration the fact that more recent values may provide a better indication of the trend and thus apply some form of decay to the weights. Moving averages (MAs) grey area MAs (SMA) N N (WMA) (EMA) Here, I’ll give a brief tutorial on how to visualize Bitcoin prices, the and the using Dash. SMA EMA Our first challenge is getting real-time Bitcoin prices. Thankfully, provides an that does just that. Coindesk API $ curl https://api.coindesk.com/v1/bpi/currentprice/USD.json {"time":{"updated":"Dec 31, 2017 19:26:00 UTC","updatedISO":"2017-12-31T19:26:00+00:00","updateduk":"Dec 31, 2017 at 19:26 GMT"},"disclaimer":"This data was produced from the CoinDesk Bitcoin Price Index (USD). Non-USD currency data converted using hourly conversion rate from openexchangerates.org","bpi":{"USD":{"code":"USD","rate":"13,935.3500","description":"United States Dollar","rate_float":13935.35}}} Nice. The prices are updated every minute so we need a service that calls this minute by minute. What we would like is a process that schedules the call every minute which is then executed in the background. API REST According to Heroku: Scheduling a job and executing a job are two related but independent tasks. Separating a job’s execution from its scheduling ensures the responsibilities of each component are clearly defined and results in a more structured and manageable system. As you would expect, Python is up to the task. The Advanced Python Scheduler (APScheduler) is a Python library that lets you schedule your Python code to be executed later, either just once or periodically. We also need a queuing system. We’ll use simply because it makes it easy to add background tasks to Python code on Heroku — my favorite . RQ (Redis Queue) PAAS $ pip install apscheduler rq redis We also need to install . There is a comprehensive guide . All I had to do from my Mac was and from my Ubuntu Redis here brew install redis sudo apt install redis-server We can then go on to create a process that listens to, and processes queued jobs. import osimport redisfrom rq import Worker, Queue, Connection listen = ['high', 'default', 'low']redis_url = os.getenv('REDISTOGO_URL', 'redis://localhost:6379') conn = redis.from_url(redis_url) if __name__ == '__main__':with Connection(conn):worker = Worker(map(Queue, listen))worker.work() This is simply a worker process that reads jobs from the given queues in an endless loop, waiting for new work to arrive when all jobs are done. Name the file worker.py Now we can go ahead to author a file named that would serve as our scheduler. We’ll use the class which is quite simple, and obtain a connection to our queue. scheduler.py BlockingScheduler from apscheduler.schedulers.blocking import BlockingSchedulerfrom rq import Queue scheduler = BlockingScheduler() from worker import connq = Queue(connection=conn) Having created and obtained a connection to the queue in our worker process, we can now schedule our job i.e making a REST call to Coindesk’s API. We’ll go ahead to author a file named You may want to install the following packages first utils.py $ pip install iso8601 requests And then import requests, calendar, timefrom iso8601 import parse_date def retrieve_current_price(endpoint): response = requests.get(url=endpoint)  
data = response.json()

updatedTime = data\['time'\]\['updatedISO'\]  
currentPrice = data\['bpi'\]\["USD"\]\['rate\_float'\]  
  
parsed = parse\_date(updatedTime)  
timetuple = parsed.timetuple()  
parsedTime = calendar.timegm(timetuple)

return Nothing groundbreaking here. We are simply making an request to the endpoint and extracting the needed information from the JSON response formatted as shown earlier. What we would like to do next is save these values to a datastore. We’ll use — a straightforward document oriented DB. http GET TinyDB $ pip install tinydb We’ll then go on to add the following snippets of code into Notice that the prices are stored in a file named utils.py bpi.db from tinydb import TinyDB, Query db = TinyDB('bpi.db')BPI = Query() db.insert({'updatedTime': int(parsedTime), 'QueryTime': int(time.time()), 'currentPrice': currentPrice}) So that looks like this utils.py import requests, calendar, timefrom iso8601 import parse_datefrom tinydb import TinyDB, Query def retrieve_current_price(endpoint): response = requests.get(url=endpoint)  
data = response.json()

updatedTime = data\['time'\]\['updatedISO'\]  
currentPrice = data\['bpi'\]\["USD"\]\['rate\_float'\]  
  
parsed = parse\_date(updatedTime)  
timetuple = parsed.timetuple()  
parsedTime = calendar.timegm(timetuple)

db = TinyDB('bpi.db')  
BPI = Query()  
db.insert({'updatedTime': int(parsedTime), 'QueryTime': int(time.time()), 'currentPrice': currentPrice})

return Now that we’ve defined our job, we can go ahead to schedule it in our file. Let’s dig up the file again and add the following snippet of code just underneath everything else in the file. scheduler.py from utils import retrieve_current_price endpoint = "https://api.coindesk.com/v1/bpi/currentprice/USD.json" #To attach the needed metadata we use a decorator#Coinbase publishes prices every minute (60 seconds) @scheduler.scheduled_job('interval', minutes=1)def retrieve_current_price_job(): q.enqueue(retrieve_current_price, endpoint) scheduler.start() Sweet. Notice that we first import the method that executes our REST call. This method is then added to the redis queue with and another such job is added every minute. q.enqueue(retrieve_current_price, endpoint) Running and should begin to populate the file every minute with the Bitcoin price indexes. scheduler.py worker.py bpi.db We now need to move over to visualizations using Dash. As a teaser, here is a look at the expected final output from this tutorial. Its dynamic, so this just gives a peek. Dash is written on top of , , and . Flask Plotly.js React.js Snip of the Dash app As you can see, it does use a bit of styling here and there and most of the styling code is borrowed from . That said, we won’t go over the styling. Go ahead and download the stylesheet. https://github.com/plotly/dash-wind-streaming Stylesheet for the Dash app A bit annoying to install but we also need to download the file that contains packages for the application . You can install them using requirements.txt here $ pip install -r requirements.txt Once that is done, we can go ahead to author a file named that would contain the code for our Dash application. app.py As usual, import a few modules. We’ll describe the functionality of some later on. import osimport datetime as dtimport time import dashimport dash_core_components as dccimport dash_html_components as htmlfrom dash.dependencies import Input, Output, State, Event import plotly.plotly as pyfrom plotly.graph_objs import * import numpy as npfrom scipy.stats import rayleigh from tinydb import TinyDB, Query from flask import Flask, send_from_directory We’ll go ahead and create our object which takes a instance as an argument. Dash Flask server = Flask('BitcoinMAvgs') app = dash.Dash('BitcoinMAvgs-App', server=server, url_base_pathname='/dash/', csrf_protect=False) Voila! we have a Dash application. Pretty useless I know but all we need to do now is define our and . To get a comprehensive dive into Dash head . layouts callbacks here The Dash describes what your app would look like and is composed of a set of declarative Dash components. On the other hand, make Dash apps interactive using Python functions that are automatically called whenever an input component’s property changes. There are components and components. layout callbacks core html we’ll go ahead to start defining our layout. First we define the root div app.layout = html.Div([...], className='main-div') We can then add sub-components to this div If you look at the final layout you’ll notice the banner. We’ll go ahead to add that. Replace the ellipsis in the snippet above with the code below html.Div([html.H2("Bitcoin prices with moving averages")], className='banner'), This basically creates a , sets the reference to its styling and adds a text. div header The next thing we need to do is create the container for our graph, its title, and the corresponding components. Go ahead and add the snippet beneath the banner component. html.Div([ html.Div([html.H3("Price(USD) " + str(dt.datetime.now().date()))], className='Title'), html.Div([dcc.Graph(id='bpi'),],className='twelve columns bpi'), dcc.Interval(id='bpi-update', interval=12000) ],className='row bpi-row'), A few explanations. As we’ve seen already the and are simply components as we know them. But now we have 2 core components. and . The component shares the same syntax as written in the open-source library. The element allows you to update components on a predefined interval. In our case, every or . Also note that these components have IDs. We’ll use these IDs when writing our callbacks. divs header html dcc.Graph dcc.Interval Graph plotly.py Interval 2 minutes 12000 milliseconds Beneath the that contains our , we’ll add 3 more components —all wrapped in their own each having a corresponding label. div graph Dropdowns divs html.Div([ html.P("Period"), dcc.Dropdown(id='period',options= [{'label': i, 'value': i}for i in ['5', '10', '15']], value='10')] style={'width': '31%', 'display': 'inline-block'}), html.Div([ html.P("Box plot Period"), dcc.Dropdown(id='box_plot_period',options=[{'label': i, 'value': i}for i in ['5', '10', '15']], value='10')], style={'width': '31%', 'margin-left': '3%', 'display': 'inline-block'}), html.Div([ html.P("Time frame"), dcc.Dropdown(id='timeframe',options=[{'label': i, 'value': i}for i in ['1', '2', '3', '4']], value='2')], style={'width': '31%', 'float': 'right', 'display': 'inline-block'}) These will dynamically control the for our averages, the grouping for our and the timeframe in hours for which to show the averages respectively. dropdowns period box-plots Having defined our layouts, we can then go ahead to write what happens when we interact with the layouts — callbacks @app.callback( Output(component_id='bpi', component_property='figure'),[ Input(component_id='period', component_property='value'),Input(component_id='box_plot_period', component_property='value'),Input(component_id='timeframe', component_property='value')], [], [Event('bpi-update', 'interval')]) What we have here is simply the for our interface which we will define shortly that describes declaratively its and . The are the properties of a particular component. Here, our inputs are the properties of the components that have the IDs , , and i.e our and our output is the property of the component with the ID which is our . decorator input output inputs value period box_plot_period timeframe dropdowns figure bpi graph Now, we can code up the method to load the data from our datastore and return the figure based on our arguments. Beneath our , we’ll add the code below graph decorator def get_bpi(N, bN, T):T = int(T)curr_time = time.time()begin_time = curr_time - T * 60 * 60 db = TinyDB('bpi.db')  
BPI = Query()  
data = db.search(BPI.updatedTime > begin\_time) First we need to determine what slice of the data to process. And this is controlled by the argument; . We simply query the datastore for the last hours of data. Now that we have the raw data, we want to extract the prices and also build a friendly format of the — we’ll show the and for each data point in our graph. timeframe T T timestamp hour minute for bpi in data: prices.append(bpi\["currentPrice"\])  
a = dt.datetime.fromtimestamp(int(bpi\["updatedTime"\]))

dtime.append(str(a.hour) + ":" + str(a.minute)) plen = len(prices) So we would like to build for our prices but remember that we have parameterized the grouping of these so that we can group our prices into various chunks — , or as you wish. box-plots box-plots 10 minute 15 minute boxtraces = []names = [] for i in xrange(0, plen, bN): y = prices\[i:i + bN\]  
ind = i + bN - 1

if (i + bN) > len(dtime):  
       
     ind = len(dtime) - 1

name = dtime\[ind\]  
names.append(name)

trace = Box(y=y, name=name, showlegend=False,  
x=\[i for j in range(len(y))\])

boxtraces.append(trace) Some explanations here. We loop through our list skipping over in steps — the parameter and for each of these data slices, we associate a label — which is the of the last datapoint in that slice. We then build a graph object using for each slice and append all those objects to a list. prices bN boxplot period timestamp Boxplot trace = Box(…) Now, we can calculate and plot our first moving average. The . The is just as its called — simple. We take an over the prices as we move across the data in chunks — which is our parameter. SMA SMA average N period SMA = []if plen > N: SMA = \[None for i in range(N - 1)\]  
  
for i in xrange(0, plen - N - 1, 1):

    y = prices\[i: i + N\]  
    sma = reduce(lambda x, y\_\_: x + y\_\_, y) / len(y)  
      
    SMA.append(sma) The Exponetial moving average — is slightly different and has the following formular EMA new EMA = [Closing price - previous EMA] x (2 / N+1) + previous EMA where N = period With that, we can go ahead and code up its implementation EMA = []if plen > N: EMA = \[None for i in range(N - 1)\]  
y = prices\[0: i + N\]  
  
avg = reduce(lambda x, y\_: x + y\_, y) / len(y)  
EMA.append(avg)

for i in xrange(N, plen, 1):  
       
    new\_ema = ((prices\[i\] - EMA\[-1\]) \* 2.0 / 11.0) + EMA\[-1\]

 EMA.append(new\_ema) Now to some things. plotly Just as we did for our traces, we also create a using the our and data. box-plot line-plot SMA EMA trace = Scatter( y=SMA, x=[i for i in xrange(0, plen, 1)],line=Line(color='#42C4F7'), mode='lines', name='SMA' ) trace2 = Scatter( y=EMA, x=[i for i in xrange(0, plen, 1)],line=Line(color='#32DD32'), mode='lines',name=str(N) + '-period-EMA' ) Nothing spectacular here, we’re simply creating a object and passing and properties. Scatter data styling With that done, we can create our plotly layout layout = Layout( xaxis=dict(tickmode="array",ticktext=names,tickvals=[i for i in xrange(0, plen, bN)],showticklabels=True), height=450,margin=Margin(t=45,l=50,r=50) ) traces = []traces.append(trace)traces.append(trace2) boxtraces.extend(traces) return Figure(data=boxtraces, layout=layout) The here is simply the list of our human friendly and our boxplots are grouped by so we want to use that too to set our . After which we can create a object instantiated with the and the . names variable timestamps bN tickvals Figure traces layout And that’s it! What’s left is to reference our the way. Just go ahead and copy the code below, and place it beneath all the code in stylesheet Flask app.py external_css = ["https://cdnjs.cloudflare.com/ajax/libs/skeleton/2.0.4/skeleton.min.css","https://fonts.googleapis.com/css?family=Raleway:400,400i,700,700i","https://fonts.googleapis.com/css?family=Product+Sans:400,400i,700,700i"] for css in external_css: app.css.append\_css({"external\_url": css}) css_directory = os.getcwd()stylesheets = ['BitcoinMAvgs.css'] static_css_route = '/static/' @app.server.route('{}<stylesheet>'.format(static_css_route)) def serve_stylesheet(stylesheet): if stylesheet not in stylesheets:

    raise Exception('"{}" is excluded from the allowed static files'.format(stylesheet))

return send\_from\_directory(css\_directory, stylesheet) for stylesheet in stylesheets:app.css.append_css({"external_url":"/static/{}".format(stylesheet)}) This snippet of code assumes the local is located in the same directory as stylesheet BitcoinMAvgs.css app.py Finally! we can run our application. if __name__ == '__main__':app.run_server() Start your server if its not already running Redis $ redis-server and execute these in separate shells $ python worker.py $ python scheduler.py $ python app.py Your application should be accessible via [http://localhost:8050/dash/](http://localhost:8050/dash/) There we have it. Dynamic moving averages of prices without writing a single line of . The complete code can be found on Bitcoin Javascript GitHub https://github.com/Viktour19/BitcoinMAvgs Drop a comment if there are any thoughts on how to make this better. Cheers!

STEPN

Coinbase

Heroku

Trace

Visualizing Bitcoin prices moving averages using Dash

Photo by Carlos Muza ( ) https://unsplash.com/@kmuza Table of Contents Part I: Setup and displaying short URLs using GraphQL Part II: Creating short URLs Part III: Creating serverless function for hashing Part IV: Short URL stats (number of clicks) (this post) Part V: User authentication Welcome back! If you want to start following along with this post, you can check out the GitHub repo for the project code, or start from the first part. With the way project is currently, we can list and create short URLs, but we can’t do anything with those short links yet. In this post we will set up routes to handle short links as well as start tracking the number of clicks and updating the link list to show number of clicks in real time. Let’s get started! Routing The routing library we are going to use is React Router (if you want to learn more in-depth about routing and react router, check this great (free) ). training Let’s start with installing the react router dependency first: $ yarn add react-router-dom To make our code more readable, we are going to create a new file called where we implement our routing logic. In this file we are going to declare which component should render, based on the URL that was requested. For example, if you navigate to root we should render the component; since will server as our main/home page, let’s rename it to . AppRouter.js http://localhost:3000/ App.js App.js Home.js Here’s how the file with simple routing logic looks like: AppRouter.js React router has two types of routers: a and a . The main difference between the two is in a way they generate URLs. For example, this would be a URL , while URL would look like this . BrowserRouter HashRouter BrowserRouter [http://localhost:8080/login](http://localhost:8080/login) HashRouter [http://localhost:8080/#/login](http://localhost:8080/#/login.) Inside of the we define a single that renders some UI ( ) if location matches the routes path ( ). To put it even simpler: if I go to , router will render the component. For example, path with value translates to to URL. Since only supports a single child, we are going to use a later on. BrowserRouter Route component={Home} path=”/” [http://localhost:3000/](http://localhost:3000/) Home **/home** [http://localhost:3000**/home**](http://localhost:3000/home) BrowserRouter Switch Finally, we need to replace component in with : <App /> index.js AppRouter ReactDOM.render(withApolloProvider( ),document.getElementById('root'),); <AppRouter /> If you run and go to you should get the exact same view as before. yarn start [http://localhost:3000/](http://localhost:3000/) In order to handle short URLs and resolve them, we need to define another . So, if user visits , we need to get the part of the URL, figure out the expanded URL by making a GraphQL query and redirecting to the full URL. If we don’t find the full URL or if there’s an error, we show a simple error message. Route [http://localhost:3000/**shorturl**](http://localhost:3000/shorturl) **shorturl** Since the short URLs are going to be dynamic, we will use a variable in the URL path to capture the short URL hash. If the router matches the URL to this route, we are going to extract the shortUrl and render a simple component that’s going to do a lookup and redirect to the full URL. Let’s create a file and implement the component. Here’s the code for that component: src/components/ShortLinkRedirect.js Let’s explain what’s happening in the code above. First, we are creating a new GraphQL query that takes a as an input and returns us an URL that matches that hash. In the component we are passing in the hash and a couple of properties from the data object (this gets injected by the container in line 31). Similarly as in previous components, we do the following (lines 15–28): $hash ShortLinkRedirect graphql Check for any errors and return an error Check if the query is still loading and return a loading message Check if we got any results or not Set the to the full URL window.location Return as we aren’t rendering anything null A thing to note in line 36 is how we’re extracting variable that’s being passed to the component from the AppRouter.js file: hash <Routepath="/:hash"render={props => (<ShortLinkRedirect hash={props.match.params.hash} />)}/> With we are indicating that we want to capture the URL parameter — we read that parameter from object and send it as a prop to , where it gets used as an input variable to the . :hash props.match.params ShortLinkRedirect GET_FULL_LINK_QUERY Try going to the web site and creating either a new short link or accessing a short link you’ve created before. Anytime you visit we try to figure out the long URL for the provided hash and redirect appropriately: [http://localhost:3000/[HASH]](http://localhost:3000/[HASH],) Short URL redirects in action! Tracking clicks Now that we have redirects working, we can think about how to store the number of clicks each short link gets. The simplest solution would be to add a field called to the existing type and use the updateLink mutation to increment the number of clicks each link got. Even though it’s an ok solution, it’s not very extensible in case we later decide that we want to track more things when short link is clicked. Clicks Link We will implement this using a new type ( ) and we will use a relation to define a connection between the link stats and links. LinkStats Let’s open the file, add a the type and create a relation to the type: graphcool/types.graphql LinkStats Link We created a stats field on type and added the directive to define a relation to the type. We do a similar thing on the type and we connect the field back to the type. Link @relation LinkStats LinkStats link Link Let’s deploy these changes to Graph.cool by running and then we can update the code and queries to increment the click count and display the click counts in component. graphcool deploy LinkList With service changes deployed, let’s update the ListList.js component first Update the to include the number of clicks and an ID in the results (updates are in ): ALL_LINKS_QUERY bold const ALL_LINKS_QUERY = gql`query AllLinksQuery {allLinks {idurldescriptionhash }}`; stats {clicks} 2. Update the render method in to get the number of clicks and show it next to the link: Link.js If you refresh the web site at this point, you should see the changes we added to the UI with number of clicks on each link being 0. On to updating the code that increments the link count! First, we need a simple mutation that’s going to take the id of the link and update the click count. Open the and follow the steps below: ShortLinkRedirect.js Update the to return the field and the field as well (updates are in bold): GET_FULL_LINK_QUERY id clicks const GET_FULL_LINK_QUERY = gql`query GetFullLink($hash: String!) {allLinks(filter: { hash: $hash }) {idurlstats {idclicks}}}`; 2. Create the for updating the click count: UPDATE_CLICK_COUNT_MUTATION const UPDATE_CLICK_COUNT_MUTATION = gql`mutation UpdateClickCount($id: ID!, $clicks: Int!) {updateLink(id: $id, stats: { clicks: $clicks }) {id}}`; 3. Create the for creating new link stats (i.e. first time someone clicks on a short link): CREATE_LINK_STATS_MUTATION const CREATE_LINK_STATS_MUTATION = gql`mutation CreateLinkStats($linkId: ID!, $clicks: Int!) {createLinkStats(linkId: $linkId, clicks: $clicks) {id}}`; This should look familiar to previous queries we did — we are passing in the variables and calling mutation to update the clicks. And in the second mutation we are creating new links stats for the provided link. updateLink 4.. Add another container to the export statements and wrap them with : graphql compose export default , graphql(GET_FULL_LINK_QUERY, {options: ({ hash }) => ({ variables: { hash } }),}),)(ShortLinkRedirect); compose(graphql(UPDATE_CLICK_COUNT_MUTATION, { name: 'updateClickCount' }) graphql(CREATE_LINK_STATS_MUTATION, { name: 'createLinkStats' }), 4. Update the function to pass in the and functions, increment the click count and call the mutation function to update it. Here’s the full file: ShortLinkRedirect updateClickCount createLinkStats ShortLinkRedirect.js That’s it! (Well, almost). If you try and access any of the short links, you’ll notice that the click count doesn’t refresh automatically; this is because we are only subscribed to new link created mutation. Unfortunately, we have to use a workaround at this point (first one in the whole series!!), because updates on relations are not supported at the moment yet (see for the discussion on this issue). here Updating the subscription The workaround is fairly simple: we will add a field to the type and update it each time we update the click count. dummy Link Open and add a field to the Link type and deploy the changes ( ). types.graphql dummy:String graphcool deploy In , set a value to the field in : ShortLinkRedirect.js dummy UPDATE_CLICK_COUNT_MUTATION updateLink(id: $id, , stats: { clicks: $clicks }) dummy: "dummy" 3. Open the file and update the query to include the event: LinkList.js LINKS_SUBSCRIPTION UPDATED ...Link(filter: { mutation_in: [CREATED, ] }) {... UPDATED 4. Add a check to in to ensure we don’t add the links twice. Since subscription is firing now on both created and updated events, we need to update the code so it doesn’t just blindly append links to the previous list. We need to check if the item that was updated is already in the list of links (i.e. click count was updated) and just return the list of previous links without doing any merges. Here’s the snippet to add at the top of : updateQuery componentDidMount updateQuery if (prev.allLinks.find(l => l.id === subscriptionData.data.Link.node.id)) {return prev;} Yay! Let’s see this in action: Auto-refresh the click count with a workaround. Great success! If you want to get the latest code, check the . GitHub repo For the next post, I might skip the link expiry feature and just dive straight into adding the user authentication (login, signup, etc.). After that, I was thinking of going through the exercise of actually deploying this — dockerizing the web site, maybe creating some tests and CI/CD pipeline, setting up SSL etc. Let me know if this is something that would interest you! Thanks for Reading! Any feedback on these series is more than welcome! You can also follow me on and . 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Building URL shortener using React, Apollo and GraphQL — Part IV: Tracking URL clicks

Search your (large) documents in seconds Back in May 2017, I was in the exam period of my 3rd year at college. A good preparation required me to go through many assignments and quizzes and answer multiple choice or open questions. Most of the answers were often found in the lecturer’s notes. So, I found myself , only to find the exactly correct answer somewhere in the notes. And I was not the only one doing this. reading tens of pages multiple times An ordinary student preparing for exams. That experience made me wonder: Is there a more effective way? Fast-forward a couple of months, I decided to kick off my Artificial Intelligence journey. I started how some of the most powerful state-of-the-art algorithms work and, eventually, began documenting my knowledge in a . learning weekly blog Seeing the rapid in deep learning and natural language processing, I decided to improvement solve the problem that many students face during their college days. Armed with my recent learnings and passion to create valuable products, I built . Asknote How does it work? is a web application which lets you find the answers you need within any document. Here is how it works: Asknote #1. Enter your email First, you need to enter your email. It is used both when you add files and ask questions. This way the system authorizes you, delivering only answers based on your own documents. Important: always keep your email in the field. Otherwise, you will receive an error message. #2. Upload your PDF file Next you need to add a PDF file of your choice. Just click , followed by . Choose File Upload PDF file Important: after uploading the file, wait until you receive a success message on the screen. Then, you will be sure your document was processed successfully. #3. Ask your question After accomplishing the above steps, just fill in your question and click . Ask You are supposed to enter a question for which you expect the answer to be hidden somewhere in the documents. You will receive the top 5 most relevant answers with their associated page number and file name. This way you can write down the correctly predicted result and read only the respective page. #4. Repeat Iterate over step and as many times as you wish. Your answers will be extracted after a careful analysis of all files. #2 #3 How it was made? Great! Now you fully understand how to use . Asknote In this section, I want to share with you some insights on the process involved in building this application. #1. Answer anything The very first challenge I faced was how to based on a given passage and a question. predict an answer I immediately dived into an extensive research to find out the most recent AI improvements in this field. I came across an amazing which lists all algorithms. Essentially, each one of them takes a question and a passage, represented as vectors, and outputs the start and end position of the answer. leaderboard Due to similarities in their implementation, I decided to first understand the math behind them. This led me to write an , explaining the best model. article For , I chose to go with the second best model (by ) because its performance is excellent for the use case. Asknote Allen Institute for Artificial Intelligence #2. Let’s do files, not text So far so good! I was receiving the correct answers and the system was working. But, as a student, Millennials, like me, can get really impatient when dealing with technology, so everything needs to happen fast and with no more than 2–3 actions. I didn’t imagine myself coping and pasting chunks of texts to search for an answer. The process needed to be simpler. To do so, I introduced The system accepts your files and analysis them to deliver the best results in the end. I wanted a reliable and stable solution, so I spent a decent amount of time perfecting the backend to perform the operations concurrently. That improved the file upload experience significantly. PDF uploads. There are still some drawbacks which I want to point out. I did my best to avoid them but, I guess, they will remain for version 0.1: Currently, you are able to add only PDF files. Any other format will be rejected. (I am planning on supporting Word docs, webpages or images in the upcoming weeks) You can upload a single file at a time. For multiple, just do them one by one. (Don’t worry, your answers will be search amongst all of the files) Images with text, within a PDF, won’t be processed. This means that you can’t find answers based on the information inside the photos. Large files (100+ pages) may sometimes take longer (5–15 sec). (I know this is sometimes annoying so I will work on improvement in the next version) #3. Different users I had the idea of different users at the start of the project, but didn’t know how exactly to execute it. I felt because it would be an additional step before experiencing the core functionality. no need of a whole authentication process, Instead, I decided to The email serves as your unique key, so when search for an answer only your documents are being displayed. This makes it possible for you to ask any question anytime, even if you reload or close the page. require an email to distinguish between different users. #4. Answers design Since the project leverages a fresh new deep learning technique, which was introduced just a couple of months ago (thus it hasn’t gone through many iterations), one can sometimes be dissatisfied with the accuracy of the end result. My solution is to navigate the user towards the right prediction but leave him to choose the answer himself. Instead of presenting the prediction with the highest probability, the system shows the top 5 most relevant answers together with their associated page number and document name. Let’s work together With my recent improvements in the field of Artificial Intelligence I came to realize that a collaboration between machines and humans can result in an immense increase in our total productivity — the power which determines economic growth. perfectly illustrates that partnership. Asknote The AI system simplifies one’s search by providing several recommendations, leaving the human to make the final decision. That results in solving complex problems such as answering any question in a matter of seconds. The project benefits me a lot. I hope you also find it useful. Excited to hear your thoughts. Thank you for the reading. If you enjoyed the article, give it some claps 👏 . Hope you have a great day!

Find the answers you need

(Structure and Interpretation of Computer Programs) 1.3.4 My 1.3.4 exercise solutions are also on Github here: https://github.com/bolducp/SICP/tree/master/exercises/chapter_01/1.3_exercises The final sub-section (1.3.4) of this section on higher-order procedures (1.3) focuses on the usefulness of not only using procedures as arguments but also as the return value of procedures. We are walked through a transformation of the and functions from earlier sections that are implemented, instead, using procedures that return other procedures. One of the main advantages illuminated by this comparison is how explicit the code built up from this style of becomes. sqrt newtons-method programming This section also spends some time explaining the mathematical equations for finding derivatives and average-dumping on the path to implementing the square-root and Newton’s method procedures. It also contains a useful, concise definition of a term that is still often thrown around when discussing programming languages, “first-class status” in reference to types of elements (pgs 76–77). Finally, I’d like to point out this gem of a paragraph, which I think beautifully articulates why the focus of this entire chapter on higher-order procedures matters, in practical terms, for the code we write everyday: As programmers, we should be alert to opportunities to identify the underlying abstractions in our programs and to build upon them and generalize them to create more powerful abstractions. This is not to say that one should always write programs in the most abstract way possible; expert programmers know how to choose the level of abstraction appropriate to their task. But it is important to be able to think in terms of these abstractions, so that we can be ready to apply them in new contexts. The significance of higher-order procedures is that they enable us to represent these abstractions explicitly as elements in our programming language, so that they can be handled just like other computational elements. (pg 76) 1.3.4 Exercises My solutions are provided in gray text blocks below each exercise question. Exercise 1.40 Define a that can be used together with the procedure in expressions of the form (newtons-method (cubic a b c) 1). To approximate zeros of the cubic x^3 + ax^2 + bx + c procedure cubic newtons-method (define (fixed-point f first-guess)(define (close-enough? v1 v2)(< (abs (- v1 v2))0.0001))(define (try guess)(let ((next (f guess)))(if (close-enough? guess next)next(try next))))(try first-guess)) (define dx 0.00001) (define (deriv g)(lambda (x)(/ (- (g (+ x dx)) (g x))dx))) (define (newton-transform g)(lambda (x)(- x (/ (g x)((deriv g) x))))) (define (newtons-method g guess)(fixed-point (newton-transform g)guess)) (define (cube x)(* x x x)) (define (cubic a b c)(lambda (x)(+ (cube x)(* a (square x))(* b x)c))) (newtons-method (cubic 2 -5 7) 1) Exercise 1.41 Define a procedure _double_ that takes a procedure of one argument as argument and returns a procedure that applies the original procedure twice. For example, if _inc_ is a procedure that adds 1 to its argument, then _(double inc)_ should be a procedure that adds 2. What value is returned by (((double (double double)) inc) 5) (define (inc n) (+ n 1)) (define (double f)(lambda (x) (f (f x)))) (((double (double double)) inc) 5) = 21 Exercise 1.42 Let f and g be two one-argument functions. The f after g is defined to be the function x ↦ f(g(x)). Define a procedure that implements composition. For example, if is a procedure that adds 1 to its argument: ((compose square inc) 6) composition compose inc (define (inc n) (+ n 1))(define (square n) (* n n)) (define (compose f g)(lambda (x) (f (g x)))) ((compose square inc) 6) = 49 Exercise 1.43 If f is a numerical function and n is a positive integer, then we can form the nth repeated application of f, which is defined to be the function whose value at x is f(f(…(f(x))…)). For example, if f is the function x↦x+1, then the nth repeated application of f is the function x↦x+n. If f is the operation of squaring a number, then the nth repeated application of f is the function that raises its argument to the 2n-th power. Write a procedure that takes as inputs a procedure that computes f and a positive integer n and returns the procedure that computes the nth repeated application of f. Your procedure should be able to be used as follows: ((repeated square 2) 5) 625 (define (compose f g)(lambda (x) (f (g x)))) (define (repeated f n)(if (> n 1)(compose f (repeated f (- n 1)))f)) ((repeated square 2) 5) = 625

SQUARE INC

SICP 1.3.4: “Formulating Abstractions with Higher-Order Procedures: Procedures as General Methods”

What do to do when you have pages of them. At any given moment, I have zillions of pieces that I have written or started to write on Medium that are not yet published. The come in three flavors (whoops, I mean categories) Articles I have already scheduled for publication. I’m done with these, I wish they would just show up in my “published category” because I can ignore them. BTW: The scheduling support built into medium is very nice. ?? Articles I haven’t finished and want to work on. ** Articles I haven’t finished and am unlikely to ever finish. I want to be able to quickly find Category 2 (Articles I want to work on) and it was frustrating for me having to click on many articles because I couldn’t tell which was which. And when I send unfinished piece out for comment, the ?? let people know. Adding the ?? and ** to the unscheduled articles removed this frustration. It saved time. It may not be a big thing, but anything that improves the “joy per hour” and “ joy per unit of frustration” is not a little thing either. This is the set of tips: 1 | 2 | 3 | 4 | 5 | 6

HackerNoon Tech Stories Archive December 31st, 2017

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