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Carousell Group

carousell

This is the first of the 'How I built' trilogy detailing the build process of all 3 of my clusters. As you may have already read in my , I built my first cluster, in April 2017 for a really superficial reason, if you haven't read it yet, I suggest you do that for a good laugh. earlier post Octopi Origins I chose Octopi, the of the word as it's the only word I could think of with a in it. Coincidentally, the prefix is also a quantifier, signifying 8 and so I thought it would be interesting to create a ludicrous 8-node Raspberry Pi cluster. unsanctioned latin plural Octopus Pi 'octo' The standard pluralised form of "octopus" in English is "octopuses". The alternative plural "octopi" is considered grammatically incorrect because it wrongly assumes that octopus is a Latin second declension "-us" noun or adjective when, in either Greek or Latin, it is a third declension noun. ( ) Wikipedia Lack of budget I had planned to have 8 nodes to fit the name but eventually found it a little too extravagant given that I was a poor student back in 2017 and I had absolutely no idea what to do with the cluster other than to admire its beauty on my desk. In the end, it was technically a as I only managed to procure 5 nodes for cheap off , but the name stuck nonetheless. Pentapi Carousell Cluster specifications |         | 1 x Raspberry Pi Model B+ | 4 x Raspberry Pi Model B |
|---------|---------------------------|--------------------------|
| CPU     | 1× ARM1176JZF-S 700 MHz   | 1× ARM1176JZF-S 700 MHz  |
| RAM     | 512MB                     | 512MB                    |
| USB     | 4x USB 2.0                | 2x USB 2.0               |
| Storage | 16GB MicroSD Class 10     | 8GB SD Class 10          | The first cluster wasn't handsome from the beginning. Before it looked the way you're probably already accustomed to by now, it looked like this: Janky beginnings Not too long after, my neat freak tendencies got the better of me and I bought a laser-cut acrylic stacking-rack for the cluster. There's always an excuse for not enough compute but there's no excuse for an unsightly cluster. But there's always budget for looks Now you may be asking, how much did I spend in total to build Octopi? All in all, I spent building this cluster. Here's the cost breakdown for each component: $183.34 Parts List | Item                                             | Qty | Cost (SGD)   | Cost (USD)* |
|--------------------------------------------------|-----|--------------|-------------|
| Raspberry Pi Model B+ (Used)                     | 1   | S$25.00      | $18.04      |
| Raspberry Pi Model B (Used)                      | 4   | S$80.00      | $57.74      |
| Anker PowerPort 5 40W 5-port USB Charger         | 1   | S$32.58      | $23.51      |
| TP-Link TL-SF1008D 8-Port Ethernet Switch        | 1   | S$20.00      | $14.43      |
| Cat 5e 30cm cable                                | 5   | S$2.50       | $1.80       |
| Cat 5e 1m cable                                  | 1   | S$2.00       | $1.44       |
| MicroUSB charging cable                          | 5   | S$15.00      | $10.83      |
| 8GB Class 10 SD Card                             | 4   | S$24.00      | $36.09      |
| 16GB Class 10 MicroSD Card                       | 1   | S$10.00      | $36.09      |
| Amazon cardboard box                             | 1   | Free         | Free        |
| Rubber band                                      | 4   | Free         | Free        |
| **GeauxRobot Raspberry Pi 5-Layer Dog Bone Stack | 1   | S$41.55      | $29.99      |
| |     | | | SGD/USD exchange rate is 0.72172 as of the time of writing
** Optional but handsome **Total** **S$254.05** **$183.34** * And that was the story of how I broke my wallet in university 3 years back. Provisioning pains For a good half a year, the furthest extent I went was flashing the SD cards with . Essentially, the cluster was a $180 on my desk, consuming 15W to produce heat, in an already hot tropical climate, and light, strong enough to disrupt my sleep cycle. Raspbian kinetic sculpture Then one day, I accumulated enough guilt to motivate myself to stop wasting electricity and start putting the cluster to work for me, and it was only then I started setting the cluster up proper. Initially, I tried provisioning the cluster one by one. With Raspbian already set up, the next thing I had to do was to enable password-less, secure communications from my local machine to the cluster and between cluster nodes. At first, that task sounded simple but I quickly realized how painful this process was. To give you some context, here are the steps I had to follow and repeat 5 times to enable password-less authentication from my machine to each node: 1. Install , a text editor 2. Copy my machine's public key into the file 3. Disable password authentication by editing Generate a public/private key pair on the node in Copy the node's public key and host key into a text editor on my machine vim authorized_keys ~/.ssh/config 4. ~/.ssh/id_rsa 5. After completing the above 5 steps, in order to enable password-less authentication between each node, I had to to: login to every node again 1. Paste the public key of into the file 2. Paste the host key of into every other node except itself authorized_keys every other node except itself /etc/ssh/ssh_known_hosts Those last 2 steps were what I'd call, n² complexity, where the number of manual operations grows to the square of the number of nodes. 😱 I ran out of gas by the time I reached the third node. Enter Ansible I searched around on how I could automate the provisioning steps above, and it was then I picked up , an open-source, software provisioning, configuration management, and application deployment tool. Ansible allows one to write Playbooks, which are essentially a list of tasks in intuitive syntax, to be run on a pre-defined list of target machines. Ansible yaml All of the above tasks that took me 2 hours was done in 10 minutes with a single command: $ ansible-playbook octopi.yml This is how I my first Ansible playbook looked like: octopi.yml --- - hosts: octopi vars: ansible_user: pi comment_re_prefix: '^[# \t]*' # SSH Key Configuration security_ssh_keygen_algorithm: 'rsa' security_ssh_keygen_bits: '2048' security_ssh_keygen_password: '' security_ssh_admin_key: ~/id_rsa.pub # SSH Configuration security_sshd_config_path: /etc/ssh/sshd_config security_ssh_port: 22 security_ssh_password_auth: "no" security_ssh_permit_root_login: "no" security_ssh_usedns: "no" security_ssh_permit_empty_passwords: "no" security_ssh_challenge_response_auth: "no" security_ssh_gss_api_auth: "no" security_ssh_x11_forwarding: "no" tasks: - name: Install common packages become: yes apt: name: vim state: present - name: Check if ssh key exists stat: path: '/home/ /.ssh/id_rsa' {{ ansible_user }} register: security_ssh_key_stat - name: Create .ssh directory file: path: '/home/ /.ssh/' {{ ansible_user }} state: directory - name: Generate ssh key command: 'ssh-keygen -t -b -N " " -f /home/ /.ssh/id_ ' {{ security_ssh_keygen_algorithm }} {{ security_ssh_keygen_bits }} {{ security_ssh_keygen_password }} {{ ansible_user }} {{ security_ssh_keygen_algorithm }} when: security_ssh_key_stat.stat.exists == False - name: Slurp public keys from all nodes slurp: src: '/home/ /.ssh/id_ .pub' {{ ansible_user }} {{ security_ssh_keygen_algorithm }} register: security_ssh_key_slurp - name: Copy public keys of all nodes into authorized_keys authorized_key: user: ' ' {{ ansible_user }} state: present key: ' ' {{ hostvars[item].security_ssh_key_slurp.content | b64decode }} with_items: ' ' {{ ansible_play_hosts }} - name: Copy local public key to authorized_keys authorized_key: user: ' ' {{ ansible_user }} state: present key: " " {{ lookup('file', security_ssh_admin_key) }} - name: Slurp host keys from all nodes slurp: src: '/etc/ssh/ssh_host_ _key.pub' {{ security_ssh_host_key_algorithm }} register: security_ssh_host_key_slurp - name: Insert all nodes into global known_hosts become: yes known_hosts: name: ' ' {{ item }} key: ' ' {{ item }} {{ hostvars[item].security_ssh_host_key_slurp.content | b64decode }} path: '/etc/ssh/ssh_known_hosts' hash_host: ' ' {{ security_ssh_hash_known_hosts }} state: present with_items: ' ' {{ ansible_play_hosts }} - name: Secure SSH configuration become: yes lineinfile: path: ' ' {{ security_sshd_config_path }} regexp: ' ' {{ item.regexp }} line: ' ' {{ item.line }} state: present with_items: - regexp: ' Port' {{ comment_re_prefix }} line: 'Port ' {{ security_ssh_port }} - regexp: ' PasswordAuthentication' {{ comment_re_prefix }} line: 'PasswordAuthentication ' {{ security_ssh_password_auth }} - regexp: ' PermitRootLogin' {{ comment_re_prefix }} line: 'PermitRootLogin ' {{ security_ssh_permit_root_login }} - regexp: ' UseDNS' {{ comment_re_prefix }} line: 'UseDNS ' {{ security_ssh_usedns }} - regexp: ' PermitEmptyPasswords' {{ comment_re_prefix }} line: 'PermitEmptyPasswords ' {{ security_ssh_permit_empty_passwords }} - regexp: ' ChallengeResponseAuthentication' {{ comment_re_prefix }} line: 'ChallengeResponseAuthentication ' {{ security_ssh_challenge_response_auth }} - regexp: ' GSSAPIAuthentication' {{ comment_re_prefix }} line: 'GSSAPIAuthentication ' {{ security_ssh_gss_api_auth }} - regexp: ' X11Forwarding' {{ comment_re_prefix }} line: 'X11Forwarding ' {{ security_ssh_x11_forwarding }} You can get this Ansible playbook at my GitHub repository. I have also written other useful tasks such as disabling the HDMI to reduce the power draw (written out of guilt after having wasted 65kWh over 6 months by letting the cluster idle) or disabling swap to extend the SD card's lifespan. cluster-ansible-playbooks My foray into Ansible was inspired by on his Pi Dramble cluster where he runs Drupal on a cluster of 6 Raspberry Pi 2B. I highly recommend checking his site out if you're just getting into Ansible. Jeff Geerling's blog Ansible was my greatest discovery back then and still remains very much relevant today, not just in my newest cluster but also in my career. After the trauma from provisioning the cluster, I took a break of several weeks to recover (and study for my exams) before starting work on hosting a Drupal blog. I did not end up using the blog as the university network was firewall-ed and not accessible from the outside world not to mention I was a lazy student then. Nevertheless, it was definitely a worthwhile project and I'll explain why with my next post in this series. Should you build this cluster? 1. Are on a really tight budget 2. Are keen on getting your hands dirty to learn how to deploy applications from the ground up 3. Have little to no experience with Linux and networks 4. Wish to explore Docker This build is for you if you: 1. Are already familiar with Linux basics 2. Have experience hosting something like a Wish to learn Kubernetes This build is not for you if you: LEMP stack 3. Should you choose to build this cluster, there are some things that you should be aware of before starting. What you should know There were quite a number of limitations when it comes to using Raspberry Pi Model 1B, most notably, the single-core 700MHz processor which may prove to be under-powered for many tasks. Notwithstanding, I shall list out the other points that I wished I was aware of before I built it. The standby power consumption of Raspberry Pi Model 1B is than that of the Model 1B+ (at 3.5W vs 1W) due to a flaw in the design of their power management hardware . Even though 2W may not sound like a huge difference, it stacks up quickly with 4 of these running 24/7. Therefore, it's almost always advisable to get the Model 1B+ and newer models. Elevated power consumption more than 3x higher (Wikipedia) The storage performance on the Raspberry Pi Models 1 through 3B+ is suboptimal. Even if you were to use the best SanDisk Extreme Pro+ SD card intended for videography usage, it would perform the same as when a standard Class 10 SD card was used. Even on a Class 10 SD card, the I/O (read/write) performance is severely bottlenecked by the shared between the Ethernet Port, the SD card slot and all USB ports. Limited storage speed single USB 2.0 bus USB 2.0 is at its core, a 480mbps connection, enabling full speed communication in only one direction at any instant, effectively halving the bi-directional communication bandwidth to 240mbps. Ethernet on the other hand, is 100mbps allowing 100mbps bi-directional data transfer at any point in time. half-duplex full-duplex, To put things into perspective, in a typical large file download operation, 480mbps of USB 2.0 theoretical bandwidth (~400mbps actual due to protocol overheads) is shared between the I/O operations to your SD card, USB flash drive, and receive/transmit operations to the Ethernet cable. | Operation                    | Read bandwidth | Write bandwidth |
|------------------------------|----------------|-----------------|
| Actual available bandwidth   | 200Mbps        | 200Mbps         |
| Ethernet maximum utilization | -100Mbps       | -100Mbps        |
| USB typical utilization      | -25Mbps        | -25Mbps         |
| | | | **Available for SD Card** **75Mbps** **75Mbps** Tabulating the bandwidth utilizations, we see that only 150mbps of actual bandwidth is available to I/O operations, amounting to a maximum of 9.38MB/s simultaneous read and write speeds, which is slightly below the maximum write speed of 10MB/s in the lowest tier Class 10 U1 SD cards. This is quite a hotly debated issue in the community albeit not very visible to those outside. The justification given by the Raspberry Pi foundation was that using a single shared USB bus keeps the manufacturing costs low, which I agree as most use-cases except mine are not demanding on the I/O aspect. My two cents Despite the restrictive hardware of a single 700MHz CPU and 512MB of RAM per node a surprising number of things can be learnt from it. Besides, most of the time, unless you go into the realm of streaming content and downloading large files, you will not hit the I/O bottleneck. Though instead of 5 nodes, I would recommend building a cluster with 3 nodes as the performance gain of two additional nodes is insignificant as compared to the additional investment it requires. If this is your first exposure to Linux, definitely build yourself one! What's next? In my next post in this series, I shall introduce the Kraken cluster which has since replaced the Octopi cluster, so stay with me! Originally published at https://ikarus.sg on June 19, 2020.

Building Cheap Raspberry Pi Cluster from Scratch

Blockchain technology is bringing the power back to shoppers eCommerce marketplace giants such as Amazon, which alone takes up to , have transformed the way people shop: empowering shoppers to easily make cross-border purchases, compare and select goods from multiple vendors on a single platform. near 50% of the U.S. eCommerce market share Consumer behaviour has also shifted in this evolution of the digital environment, with 64% of respondents in a stating that they begin product searches at marketplaces, citing product variety and price as key motivators. global Amazon and Pymnts.com survey With the evolution of the eCommerce industry and more discerning shoppers with no lack of choices, this presents a new set of challenges and opportunities for industry players. In this competitive landscape, much can be done to improve current systems to maximise business efficiencies and opportunities. Blockchain technology — a perfect fit for the eCommerce industry? Enter blockchain technology — a distributed ledger technology steeped in immutability and transparency with the potential to streamline the eCommerce industry’s complex system of supporting multiple players. Blockchain technology will not only enable varying businesses to enjoy different advantages, but also help enhance the buying experience for shoppers in areas such as: By enabling a distributed peer-to-peer network, unnecessary intermediaries are removed, therefore reducing merchant mark up costs, which translates to cost savings for shoppers Cost efficiency: Providing a borderless payment solution through tokenization Convenience: A decentralised network removes the need for the middleman, protects user data and privacy by preventing any centralised access with its distributed nature. Smart contract technology also helps to enable automated escrow services, preventing any cases of fraud Reliability & security: Here, we further explore some current pain points shoppers face and how blockchain technology could help bring the power back to the people. “ I wish there was a way to forgo expensive third-party payment charges…” Online transactions are typically fraught with , including transaction, currency conversion and merchant mark up fees, which shoppers are often unaware of. To optimise this process, many companies have explored means to bypass external payment gateways and their limitations, while shoppers have looked into bank alternatives such as and . extra charges and hidden fees Transferwise Xfers The reduction of intermediaries, such as third party credit card transaction fees, will enable merchants to reduce costs, which translates to lower mark up prices and in turn leads to more cost savings for shoppers. More companies are also exploring alternatives such as proprietary payment services, with , a native payment gateway which offers an integrated payment solution in the ecosystem to simplify the payment process for both buyers and sellers. Singapore mobile marketplace startup Carousell launching Caroupay last year Asset tokenization, which issues rights to an asset through a digital representation of it could be a way to enhance shoppers’ experience by simplifying and making the payment process more convenient. Through placing it on the blockchain, it comes with the added advantages of traceability, immutability and irrevocability in the system. , is one example where shoppers can pay with , their native digital token, which removes the need for third-party fees such as transaction and service fees thus bringing cost savings to shoppers. QuuBe, e-commerce site Qoo10’s new blockchain-powered counterpart Q*Coins Blockchain smart contracts, which are digital protocols developed for automated proofing conditions of a contract between two or more parties (or otherwise best described as an automated vending machine on simpler terms), could also help eliminate the need for costly intermediaries and prevent fraud. , a blockchain-based project by Arcadier, a leading online marketplaces builder utilises smart contracts in its ecosystem to facilitate peer-to-peer transactions with the options of funds escrow, eliminating the need for costly intermediaries. ArcadierX “Is my data safe here?” A 2018 global survey on Internet Security and Trust has found that , being cautious about online transactions due to privacy and security concerns. over half of internet users are discouraged by the lack of trust online In 2014, an compromised 145 million users’ private information, while Marriott International shockingly had an for 4 years from 2016 to 2018. Such cases highlight the reality and the growing threat and impact of business data breaches. eBay data breach undetected data breach of 500 million customers The growing . This highlights the importance for the eCommerce industry to take action and explore ways to improve the current system before any potential oversight cause irreversible damage to their business and reputation. global average cost of a data breach (defined as both direct and indirect costs to the business) has risen up by 6.4 percent in 2018 over the previous year to $3.86 million Blockchain offers an opportunity to securely manage eCommerce databases through distributed ledger technology, where data and transactions can be stored in a distributed, immutable and irrevocable ledger. Through this decentralised peer-to-peer network, any single point of failure that is present in traditional centralised databases can thus be fully eliminated. is an example of a fully decentralised peer-to-peer only marketplace where data is distributed across the network instead of being stored in a central database, so the power is transferred from a central authority to individuals. Although this helps to minimise cases of data breaches and fraud, it also shifts the responsibility of ensuring safety and security to the individual. Openbazaar Of course, there are also current limitations of blockchain technology with regards to issues of speed and scalability in a decentralised network that companies have to take into consideration. For instance, some companies are choosing to integrate blockchain technology to proven areas such as data storage and payments while industry standards and technology continue to mature. , an eCommerce marketplace, is enhancing their platform with blockchain technology — building its decentralised infrastructure on top of its centralised base, in areas such as payments, data verification and smart contract execution. Storiqa “ Fake reviews, sellers not delivering the products, counterfeit goods… [there’s] too many reasons not to trust the current system!” The growth of the eCommerce industry, with (a threefold increase from 2014) presents lucrative opportunities for players looking to capture a slice of the market. retail sales projected to rise to US$4.88 trillion in 2021 With that growth, however, comes more bad players in the market looking for ways to exploit the system. is a huge issue, with the and the in the industry Fake reviews Federal Trade Commission recently bringing its first case against an Amazon merchant’s fake reviews rise of counterfeit goods Ironically, this is where trustless systems could help play a part in demystifying and rebuilding trust in the industry. As a distributed ledger system, blockchain enables a systemised way of ensuring provenance through a decentralised peer-to-peer ledger which enables the tracking of transactions and the flow of goods. Tmall Global, Alibaba’s international e-commerce platform, has integrated a using blockchain technology set to be able to trace imported goods every single step of the process, where users can simply scan a QR code and receive all information regarding the product. Likewise, Reebonz, an online luxury marketplace, has also with blockchain startup Vechain, to tackle fraud cases by enabling tracking and authentication for the luxury goods sold on its platform. global tracing system “Traceability for TMG” recently signed a Memorandum of Understanding (MoU) The benefits are not limited to the transaction of goods and services but also in other areas such as eCommerce ratings and reviews. For example, on ArcadierX, the distributed nature of blockchain technology would help prevent fake reviews and even allow sellers to bring their reputation with them on multiple marketplaces. Similarly, , another decentralised marketplace builder, is hoping to enable a transparent and automated escrow system through using smart contracts built on the Ethereum blockchain. NeoPlace Empowering shoppers through rebuilding trust Blockchain technology represents a paradigm shift in the system, transforming shoppers’ role and experience in the eCommerce ecosystem. No longer are they passive consumers, but rather active participants gaining back control of their data and privacy through decentralisation. As the technology continues to mature and gain traction, shoppers can look forward to more impactful innovations and disruptions that could further enhance their shopping experience. ** (The writer is the CCO & Co-Founder at ArcadierX) Disclaimer: Nothing written, posted or said by representatives of ArcadierX , its community managers, or community members should be interpreted as, taken as, or constitutes investment advice. All written comments are opinions of individuals and any investment is a risk that individuals take themselves. ArcadierX is leading marketplace builder Arcadier ’s blockchain initiative to onboard users with a blockchain enhanced platform. For more insights and developments about blockchain and eCommerce, check us out on Medium . What are some other ways blockchain technology can disrupt the eCommerce ecosystem? Continue the discussion with us on Telegram .

Blockchain technology is bringing the power back to shoppers

I have been having issues setting up bootstrap carousels on rails. It took me days before I finally found a way out. At a point, all articles and videos are not helping even after following the whole steps religiously. Lets’s skip all that and get to work. Let create a new rails app: rails new carousels We wait for rails to finish the app creation. Once we are done with that, we go into our: app/assets/stylesheets then rename "application.css" to "application.scss" Once that is done, let us head over to the bootstrap website and copy the download the carousels sample code to our local system. Install bootstrap, jquery, and popper.js to our application. yarn add bootstrap jquery popper.js Also add the bootstrap link to the head tag of your . app/views/layout/application.htm.erb <%= stylesheet_link_tag "https://cdn.jsdelivr.net/npm/bootstrap@5.0.2/dist/css/bootstrap.min.css" %> After that, go to , click on the download examples, then extract the file to your system. https://getbootstrap.com/docs/5.0/examples/ Go into the bootstrap extracted folder and locate the folder, not folder. Open the folder, copy the file and move it to your application stylesheet folder. carousel carousel-rtl carousel carousel.css Your folder should consist of the file and carousel.css file. app/assets/stylesheets application.scss Rename: app/assets/stylesheets/carousel.css to app/assets/stylesheets/carousel.scss Go into your and add import the to it by adding the code below to your file: app/assets/stylesheets/application.scss carousel.scss application.scss @import 'carousel'; Also, go into your and the import bootstrap. app/javascripts/packs/application.js import  'bootstrap' We need to generate a view and a controller for our app. We can do that using the scaffold command. Let us generate a “post” view and controller for our app. We can do that by using the command below: rails generate scaffold post After that, we need to run migrations on the database for the scaffold command to take effect on the schema: rails db:migrate Once that is done, we can start our app by: rails s The command above will start the rails server. The next thing is to route the root path of our app to page. post#index Go to your , add the code: config/routes.rb root to: 'posts#index' The code below will route our index page to the post index page. localhost:3000 Next, we go into our index file in the views folder to update it to display our carousels. app/views/posts/index.html.erb Let us go back to the carousel folder we downloaded on bootstrap. Go into the folder, open the index.html file and copy the code from: <div id="myCarousel" class="carousel slide" data-bs-ride="carousel">
  ..........
  ..........
 </div> Paste the copied code to your index page and refresh your browser. Tadaaa!!! Your carousels should work fine now. I hope this article helps. Suggestions are highly welcomed.

Building Rails Carousels Using Bootstrap

Web Performance Optimization I am one of the CoE members in . Our company invests startups, and I help them to grow. Last time, I was helping a Vietnamese company by making their web faster. Cool! See how . This article is from the journey exploring the SSR support of the carousels. It ends with making the . GSShop web performance affects your business Vue.js vue-slick-carousel CSR (Client Side Rendering) With A Spinner The site is a SPA(Single Page Application) made with . Vue.js, like , is one of the famous tech stacks of modern web development. Despite the SPA's many advantages, it has the disadvantage of long loading time due to the . The long loading time is because the browser doesn't know what to render on the screen until the browser evaluates javascript. So it usually put the spinner to say, "Please, don't leave. We're working on it." I wish the magic circle works, but It doesn't. Vue.js React CSR(Client Side Rendering) SSR(Server Side Rendering) With Placeholders allows the server to render the HTML so that the browser can quickly show what visitors want without evaluating javascript. (like for React) provides best practices, including SSR, to help us build fast web sites. SSR(Server Side Rendering) Nuxt.js Next.js We've enabled SSR using Nuxt.js to get rid of the spinner and quickly render the site's contents. SSR made the browser to render fast without having to wait for evaluating the javascript. But this site is made up of many carousel components. The carousel component doesn't support SSR, so it can't quickly render important things like promotions. We removed the spinner, rendered contents instantly, but had to put a lot of placeholders for the carousels. As with before, the contents of the carousels were rendered only a long time after it evaluates the javascript. Wanted: Server Side Rendering Vue.js Carousel Although it looked much better than before, visitors didn't come to see the placeholders. To truly improve UX, we needed a carousel with SSR support. Top 5 Vue.js Carousels To see which carousels work with SSR best, I tested the top 5 carousels on GitHub(except , which has a specialty in 3d rendering). vue-carousel-3d 🏆 Swiper component for @vuejs vue-awesome-swiper A flexible, responsive, touch-friendly carousel for Vue.js vue-carousel vue-concise-slider,A simple vue sliding component vue-concise-slider A carousel component for Vue.js vue-agile Vue component for Slick-carousel vue-slick Example Settings I prepared the SSR examples for the carousels using Nuxt.js( , , , , , ). Also, you can run those on codesandbox( , , , , , ). vue-awesome-swiper vue-agile vue-carousel vue-concise-slider vue-slick vue-slick-carousel vue-awesome-swiper vue-agile vue-carousel vue-concise-slider vue-slick vue-slick-carousel The Examples: Are created on top of Nuxt.js with universal(SSR) mode. Are wrote by following the examples of the components. Have image items as we're likely having one or more in real life. Have identically styled. No dots, no arrows. Profile Configuration: Build for production and run a local server to minimize network Interference. Chrome performance profile with Fast 3G Network + 4x slowdown CPU throttling. vue-agile , vue-carousel , vue-concise-slider , vue-slick These carousels do not support SSR. Trying to render these carousels on the server will throw errors. In most cases, the carousels try to access the through object to manipulate the . However, this problem occurs because that does not exist on the server. browser window DOM elements To avoid the errors, The carousels should be registered on and wrapped by component. Here're the demos( , , , ) and codesandboxes( , , , ) client-side only mode client-only(no-ssr) vue-agile vue-carousel vue-concise-slider vue-slick vue-agile vue-carousel vue-concise-slider vue-slick Component Template < = > div class "carousel-wrapper" < > client-only < = > agile :options "options" < = = = > div v-for "i in 5" :key "i" class "img-wrapper" < = img :src "`./$ {i} -200x100.jpg`" /> </ > div </ > agile </ > client-only </ > div The carousel components need to be wrapped by  client-only to avoid the error. Server Render Result < = > div class "carousel-wrapper" < > client-only < = > agile :options "options" < = = = > div v-for "i in 5" :key "i" class "img-wrapper" < = /> img :src "`./${i}-200x100.jpg`" </ > div </ > agile </ > client-only </ > div The server renders blank inside client-only. The browser will render the carousel after it evaluates the necessary javascript. Performance Profile After receiving the server's response, the browser must evaluate the javascript to draw the carousel. Images included in the carousel children can only be downloaded and painted afterward. vue-awesome-swiper is the most popular Vue.js carousel component. vue-awesome-swiper offers a . You write the rendered DOM structure manually into the component template then the browser runs the to render again. Thus the server just renders what you wrote in the component template without evaluating the carousel script. It means the SSR result doesn't respect any options passed to the carousel. Below is a vue-awesome-swiper with options. Here's the & . vue-awesome-swiper special way for server rendering custom directive slidesPerView: 3 demo project codesandbox Component Template < = >
  < v-swiper:mySwiper= >
    < = >
      < v- = :key= = >
        <img :src= />
      </ >
    </ >
  </ >
</ > div class "carousel-wrapper" div "options" div class "swiper-wrapper" div for "i in 5" "i" class "img-wrapper swiper-slide" "`./${i}-200x100.jpg`" div div div div The custom directive v-swiper is for browsers, server renderer doesn't evaluate it. Server Render Result < = > div class "carousel-wrapper" < = > div v-swiper:mySwiper "options" < = > div class "swiper-wrapper" < = = = > div v-for "i in 5" :key "i" class "img-wrapper swiper-slide" < = /> img :src "`./${i}-200x100.jpg`" </ > div </ > div </ > div </ > div The server renders the template as it is. Browser shows a default vue-awesome-swiper having one slide in it. After the browser evaluates the component directive, It updates the carousel for the given options. Performance Profile Browsers can download and paint images in the early stages because the first HTML response contains images. As soon as the browser evaluates the script, It can render the carousel with images. But it seems to render the carousel takes more time than the other carousels. It is because of the heavier script. Not only downloading but also evaluating the javascript takes longer. Writing SSR Support Carousel: vue-slick-carousel Ok. I tested the most popular carousels. I also looked around the other carousels. But all seemed not working. And I excluded carousels in the UI Frameworks because they do not provide rich features we needed. Here it is. I made the because of the reasons. Long story short, I ended up writing the vue-slick-carousel by porting the . I tested by matching the result of the for the vue-slick-carousel to the result of the for react-slick. I kept in mind that the rendering result works for every carousel settings. Here's the & . vue-slick-carousel react-slick vue-server-renderer react-dom server example codesandbox Component Template < = > div class "carousel-wrapper" < = > VueSlickCarousel v-bind "slickOptions" < = = = > div v-for "i in 5" :key "i" class "img-wrapper" < = img :src "`./$ {i} -200x100.jpg`" /> </ > div </ > VueSlickCarousel </ > div vue-slick-carousel works well on the server. Therefore, you can write the template in the usual way, without the client-only tag. Server Render Result < = > div class "carousel-wrapper" < = = > div dir "ltr" class "slick-slider slick-initialized" data-v-6bed67a2 < = > div class "slick-list" data-v-6bed67a2 < = = > div class "slick-track" style "width:433.33333333333337%;left:-100%;" data-v-4dc0f449 data-v-6bed67a2 < = = = = = > div tabIndex "-1" data-index "-3" aria-hidden "true" class "slick-slide slick-cloned" style "width:7.6923076923076925%;" data-v-4dc0f449 < > div data-v-4dc0f449 < = = = > div tabIndex "-1" class "img-wrapper" style "width:100%;display:inline-block;" data-v-4dc0f449 < = > img src "./3-200x100.jpg" data-v-4dc0f449 </ > div </ > div </ > div  < = = = = = > div tabIndex "-1" data-index "9" aria-hidden "true" class "slick-slide slick-cloned" style "width:7.6923076923076925%;" data-v-4dc0f449 < > div data-v-4dc0f449 < = = = > div tabIndex "-1" class "img-wrapper" style "width:100%;display:inline-block;" data-v-4dc0f449 < = > img src "./5-200x100.jpg" data-v-4dc0f449 </ > div </ > div </ > div </ > div </ > div </ > div </ > div The server fully make the DOM elements and sends them to the browser. The browser can render on the screen without evaluating any javascript. Performance Profile The browser renders the carousel right after the first HTML response. Since the carousel was rendered quick, downloading images can also be started fast. Undoubtedly, the vue-slick-carousel can show content the fastest and prepare the image resources it needs. The actual site contains a much heavier script, and this performance gap will be even more significant. Component Support Completes The SSR All components used by the site must support it for the server to fully render. Thus, the site can deliver what visitors want quickly. Otherwise, In many cases, Trying without the support of components can make the site even slower due to the heavier HTML. Component support completes the Server Side Rendering. My last project had the same issue. To show content to users faster, we enabled SSR, but this was not possible because no Vue.js carousel supported it. The server is now able to fully render the content using the vue-slick-carousel so that it can deliver content to visitors faster. What's Next? Since I started this project to improve performance, I'd like to focus on the goal. And the vue-slick-carousel itself is a new project that has been only a few months old. I want to make it stable. Every issue and PR are welcomed. Your help can make this project mature. Finally, Thank you, react-slick contributors. I'd like to contribute as much as I can while I'm working on this. Besides the project, I'm thinking of two more articles to share what I learned in the last project. Perhaps due to the population differences, I feel that the react ecosystem is more versatile and mature than the Vue.js ecosystem. Just as is the case with the vue-slick-carousel, I guess it's worth sharing "How to port the react component for the Vue.js." And "Vue.js SSR the hard parts" that I struggled with in my last project.

Server Side Rendering Carousels in Vue.js: Blazing Fast Loading

Short answer — it’s risky, but it can also work depending on how you do it in terms of UX. Website carousels have definitely decreased in popularity since a few years ago, but you can still find some here and there — most notably on e-commerce websites that avoid refreshing their UI very often. Carousels used to be a pretty popular thing. It’s a way to cramp 3–5 (or more?) images in the same space by making them switch at an even interval. It adds some movement to a website, which makes it feel more alive, but if done incorrectly, which is often the case, they can cause real confusion for the user, not to mention — nausea. Consider why you want to have a carousel at all Having a carousel on your homepage, because other websites have it is not a good enough reason. Think about whether it adds any value to your website visitors, specifically to their user experience. If done correctly, a carousel can promote your product features, inform your customers of current offers and help them navigate to a specific product. Consumers are generally attracted to large scale images, which normally go with a carousel and the auto-movement allows you to expose more information while preserving space from your homepage. You should also carefully consider, whether an alternative to the carousel might be a far simpler and more elegant solution. An example would be to just use static images on your homepage in a preferred grid, containing all the information you want to show. This is a simpler solution, which also works well on mobile (as opposed to a carousel). I’m using “simpler” since you won’t have to be careful about the pitfalls of having an auto-rotating container. If the content of the carousel is not very carefully curated to be relevant, high-quality and mobile-friendly, the user experience that comes with it will just be unpleasant. Still, if you decide to go for the carousel, please consider the following. The slide sequence This one should be chosen very carefully. Imagine the carousel images like a funnel. The first image you chose will get the most views. Each next one will get significantly less noticed. Visitors simply don’t stick around at the top of the website to wait for all the photos of a carousel to autorotate. They might see the first and the second one and immediately scroll down or click on a link to go to a different page. Consider this when you pick the sequence of your carousel images. Website content paths If you decide to have one (or all) of your carousel images to be placeholders for buttons that lead to a specific website feature or content, be sure to have the option to reach this same feature or content through another place as well. Users often skip the carousel entirely, subconsciously ignoring it, especially if it resembles an ad too much (there’s actually something called “banner blindness”). Another use case is if the internet connection is too slow and the carousel doesn’t load fast enough. The user will immediately go looking for the content he’s interested in, and if the only path to it is in the carousel, she simply won’t find it. Clear manual controls This one should sound very straightforward, but it’s surprising how many websites get it wrong. Just be sure the manual controls are clearly visible. Sometimes they’re just little transparent dots somewhere on the side of the carousel that clash with the image in the background and it’s completely impossible to see them. Might as well not have controls at all. Carousel rotation speed This is a tricky one. If the rotation speed of the carousel slides is too fast, the users may feel like they don’t have enough time to see the content of each one. If, on the other hand, it’s too slow, they will lose patience waiting for the next image and will simply move on. It really depends on how much text you have on each slide, but a good benchmark seems to be 5 to 7 seconds per slide for slides with just a few words. Pause on autorotation The user should have control over the carousel’s autorotation. A good practice is to do this on hover. That way, if the visitor decides to focus on a slide, they can just hover and spends as much time on it as they like. Stop of autorotation Another important carousel behaviour should be stopping the autorotation after any kind of interaction from the user. That means if a visitor uses the controls to switch to a different slide, the autorotation should stop. Otherwise, the user will change slides to focus on a specific one and the slide would change again automatically. Frustrating! Mobile gestures In a mobile context, the carousel should support screen gestures. Simple as that! People are used to pinching and swiping on their phone so the carousel should take this into consideration — specifically the swiping part to change slides. Legible slide text Be wary when directly transferring a website carousel into mobile. If there’s a lot of text on a certain slide, that same text will not be legible on a smaller screen. Either adjust the slide’s text to accommodate for the smaller screen, or create a different slide for the mobile version with less text. Carousel content load speed Users have even less patience when it comes to content being loaded on a mobile device. If the carousel takes more than a second or two to load it will be entirely ignored. When choosing the content of your slides, consider how fast it loads not only for web but for mobile as well. If it seems slow on web it’ll feel like it’s taking ages on mobile. Conclusion As one of the leading design agencies in Singapore, we’ve had a lot of discussions with clients who want to have a carousel on their homepage. Although we’re not entirely against it, it’s sometimes questionable what the added value would be and often times it seems like an unnecessary complication, compared to using static images with content. Always consider why you want to include a certain element on your homepage and what its effect might be for your user’s experience. : Insights taken from research performed by Source Baymard Institute

Is It Still OK To Have A Carousel On Your Website

STEP 1: Create divs inside of your page that will contain the carousel elements .gallery.gallery-main.gallery-main-imageimg(src=”/images/gallery3.jpg”).gallery-filmstripa(href=””)img(src=”/images/gallery1.jpg”)a(href=””)img(src=”/images/gallery2.jpg”)a(href=””)img(src=”/images/gallery3.jpg”)a(href=””)img(src=”/images/gallery4.jpg”)a(href=””)img(src=”/images/gallery5.jpg”) STEP 2: Set the styles for all of the elements inside of your carousel: The Displayed Image Gallery: The div around the display for the selected image /*set styles for the wrapper around the image that will be displayed on click*/ .gallery {background-color: black;} .gallery > .gallery-main {position: relative;height: 400px;overflow: hidden;} The div that contains the div that contains the image itself /*set styles for the inner container for the image that will be displayed on click*/ .gallery > .gallery-main > .gallery-main-image {position: absolute;top: 0; bottom: 0;right: 0; left: 0;} The image itself /*set styles for the image itself*/ .gallery > .gallery-main > .gallery-main-image > img {display: block;margin: 0 auto;max-height: 100%;max-width: 100%;height: 400px;} The Filmstrip that contains thumbnails of the images to be displayed: The container for the filmstrip /*set styles for the filmstrip container*/ .gallery > .gallery-filmstrip {position: relative;height: 280px;margin-top: 10px;} Everything inside of the filmstrip /*set styles for everything inside the filmstrip container*/ .gallery > .gallery-filmstrip > * {position: absolute;top: 0;left: 0;} Position everything inside of the filmstrip in the center /*position everything inside the filmstrip in the center*/.gallery > .gallery-filmstrip > * {position: absolute;top: 0;left: 0;} Animation for the images in the filmstrip /*set animation class to the filmstrip on click*/.gallery > .gallery-filmstrip-animated > * {transition: transform 1s, opacity 1s;} Set a height and width for all images in the container /*set a height and width for the gallery filmstrip images*/.gallery > .gallery-filmstrip img {height: 200px;width: 200px;} STEP 3: Create functions using and that will allow you to iterate through your images using the styles and animations you just created. jQuery Javascript Initialize the Gallery const initializeGallery = function() {positionGalleryFilmstrip(0, false) $(‘.gallery-filmstrip > *’).on(‘click’, function(event) {event.preventDefault();const cell = $(this);const index = cell.index()console.log(‘CLICKED’, index)positionGalleryFilmstrip(index-2)})} initializeGallery() Determine the indices that will be visible in the filmstrip and use an offset to to ensure that whatever index we are on gives us either a result of 0, 1, 2, 3, 4. How do we do this by using a for loop and modulo const visibleIndicies = function(totalNumberOfCells, numberOfVisibleCells, offset){let visible = []for (let index = 0; index < numberOfVisibleCells; index++) {visible[index] = (index+offset) % totalNumberOfCells}return visible} Determine the Z Index, Opacity, and Transform for each position depending on where it is on the filmstrip const zIndexForPosition = function(position){return ((position === 0 || position === 4) ? 1 :(position === 1 || position === 3) ? 2 :3)} const opacityForPosition = function(position){return ((position === 0 || position === 4) ? 0.4 :(position === 1 || position === 3) ? 0.7 :1)} const transformForPosition = function(position){return ({0: ‘translateX(160px) translateY(31px) scale(.8)’,1: ‘translateX(300px) translateY(31px) scale(1)’,2: ‘translateX(500px) translateY(31px) scale(1.3)’,3: ‘translateX(700px) translateY(31px) scale(1)’,4: ‘translateX(860px) translateY(31px) scale(.8)’,})[position]} Determine the index of the image (cell) based on its location in the filmstrip (array) const visibleIndicies = function(totalNumberOfCells, numberOfVisibleCells, offset) {let visible = []for (let index = 0; index < numberOfVisibleCells; index++) {visible[index] = (index+offset) % totalNumberOfCells}return visible} the most complex part of the function — positioning the image so that it applies the css styles to that specific index to be displayed within an array that contains 5 image elements const positionGalleryFilmstrip = function(offset, animate=true){const filmstrip = $(‘.gallery-filmstrip’)const numberOfCells = 5;const cells = filmstrip.children()if (offset < 0) offset += cells.lengthconst visibleCells = visibleIndicies(cells.length, numberOfCells,offset)if (animate){filmstrip.addClass(‘gallery-filmstrip-animated’)}else{filmstrip.removeClass(‘gallery-filmstrip-animated’)}cells.each(function(index){const cell = $(this)let position = visibleCells.indexOf(index)if (isBefore(index, visibleCells, cells.length)){cell.css({display: ‘block’,zIndex: ‘0’,opacity: ‘0’,transform: ‘translateX(100px) translateY(31px) scale(.6)’,})}else if (isAfter(index, visibleCells, cells.length)){cell.css({display: ‘block’,zIndex: ‘0’,opacity: ‘0’,transform: ‘translateX(890px) translateY(31px) scale(.6)’,})}else if (position === -1){cell.css({display: ‘none’,zIndex: ‘0’,opacity: ‘1’,transform: ‘’,})}else{cell.css({display: ‘block’,zIndex: zIndexForPosition(position),opacity: opacityForPosition(position),transform: transformForPosition(position),})}if (position === 2){const src = cell.find(‘> img’).attr(‘src’)const image = $(‘<img>’).attr(‘src’, src)const gallery = filmstrip.closest(‘.gallery’)const galleryMain = gallery.find(‘> .gallery-main’)const currentImageWrapper = galleryMain.find(‘.gallery-main-image:first’)const nextImageWrapper = currentImageWrapper.clone()const nextImage = nextImageWrapper.find(‘> img’)if (nextImage.attr(‘src’) === src) return;nextImage.attr(‘src’, src)galleryMain.prepend(nextImageWrapper)currentImageWrapper.fadeOut(function(){currentImageWrapper.remove()})}})} Whoa!! What is happening here? Let’s break it out and go over it step by step: create a function that positions the gallery filmstrip and set that to animate=true assign some variables that will contain the filmstrip element, the number of cells, and the children of the filmstrip const positionGalleryFilmstrip = function(offset, animate=true){const filmstrip = $(‘.gallery-filmstrip’)const numberOfCells = 5;const cells = filmstrip.children()} if the offset is less than zero then we want to add the total number of cells to that amount. For example if we are at offset -1 and we have an array of images with the length 39, our new offset value will be 38. if (offset < 0) offset += cells.lengthconst visibleCells = visibleIndicies(cells.length, numberOfCells, offset) if the above condition is true, which means the cell is visible then pass the new offset, length, and number of cells into the function visibleIndices. We will then store the value of this function into visibleCells if animate is true then we will add the animated class to the filmstrip, otherwise do not add that class if (animate){filmstrip.addClass(‘gallery-filmstrip-animated’)}else{filmstrip.removeClass(‘gallery-filmstrip-animated’)} now apply the following css styles to each cell which will give it the opacity, zIndex, and transform functions we need for each cell depending on its position in the filmstrip cells.each(function(index){const cell = $(this)let position = visibleCells.indexOf(index)if (isBefore(index, visibleCells, cells.length)){cell.css({display: ‘block’,zIndex: ‘0’,opacity: ‘0’,transform: ‘translateX(100px) translateY(31px) scale(.6)’,})} else if (isAfter(index, visibleCells, cells.length)){cell.css({display: ‘block’,zIndex: ‘0’,opacity: ‘0’,transform: ‘translateX(890px) translateY(31px) scale(.6)’,})}else if (position === -1){cell.css({display: ‘none’,zIndex: ‘0’,opacity: ‘1’,transform: ‘’,})}else{cell.css({display: ‘block’,zIndex: zIndexForPosition(position),opacity: opacityForPosition(position),transform: transformForPosition(position),})} Now we need to assign the attribute to the images that will allow us to fade it out and in if (position === 2){const src = cell.find(‘> img’).attr(‘src’)const image = $(‘<img>’).attr(‘src’, src)const gallery = filmstrip.closest(‘.gallery’)const galleryMain = gallery.find(‘> .gallery-main’)const currentImageWrapper = galleryMain.find(‘.gallery-main-image:first’)const nextImageWrapper = currentImageWrapper.clone()const nextImage = nextImageWrapper.find(‘> img’)if (nextImage.attr(‘src’) === src) return;nextImage.attr(‘src’, src)galleryMain.prepend(nextImageWrapper)currentImageWrapper.fadeOut(function(){currentImageWrapper.remove()})}})} last but not least we need to determine if a cell is before or after the cell const isBefore = function(index, visibleCells, cellsLength){let beforeFirstIndex = visibleCells[0]-1if (beforeFirstIndex < 0) beforeFirstIndex += cellsLengthreturn index === beforeFirstIndex} const isAfter = function(index, visibleCells, cellsLength){let afterLastIndex = visibleCells[visibleCells.length-1]+1if (afterLastIndex > cellsLength) afterLastIndex -= cellsLengthreturn index === afterLastIndex}

Creating a Carousel Using Only Jade(Pug), Javascript, jQuery and CSS

Learn How to Create A Simple Carousel with React.js

Do you want your carousel to extend the full width of the browser window? Do your images look cut off or have unwanted padding on the left and right? Bootstrap In this tutorial we will take a closer look at the Bootstrap 4 carousel and determine the best approach in making it full width and responsive. Problem If you use the from the Bootstrap 4 documentation you will notice the carousel anchor links do not wrap the entire image. In most cases, you will probably want the opposite. So for this example I am going to make this adjustment to the code. carousel code snippet Each image has the class which tells the browser to only scale the image down if it does not fit in the smaller width. But for wide windows it doesn’t scale up. But since you want to go full width, your images will appear cut off on really large screens. .img-fluid .img-fluid {max-width: 100%; height: auto;} In order to fix this, you will need to add the CSS rule below to your stylesheet to force your carousel image to always be full width. I first tried so the image height would stay in the right proportion. But that did not work because the parent element is set to . Changing the height to 100% fixed this. height:auto; .carousel-item display:flex /*Forces carousel image to be 100% width and not max width of 100%*/.carousel-item .img-fluid { width:100%; height:100%; } /*Forces carousel image to be 100% width and not max width of 100%*/.carousel-item .img-fluid {width:100%;height:100%;} This is not mobile friendly because it dramatically decreases page load speed because the images have a large file size (more pixels = more load time). This approach forces you to choose the widest image size and then load it on mobile. One of the most common causes of slow websites is large images, so we will want to correct this in our final solution. Above, notice how the carousel looks super small on mobile and HUGE on wide desktops? This doesn’t look right. In the next section we will improve the following: Improve the load speed by serving the right sized image at the right breakpoint Fix the layout aesthetics of the image sizes being too small or too large View demo of this example Solution HTML5 has introduced two different ways to handle responsive images: the and . Img srcset lets you specify different image resolutions based on window size and pixel density of the screen. This solves the page load problem but would not be able to make the xs and xl image proportions look better. We want the mobile image to be square and the desktop image to be a rectangle so we need more “art direction” control on what image is used and when. picture element srcset img attribute The picture tag is designed for this scenario, so we will use this instead. Keep in mind, you will need to use a to support IE11 and below because these versions do not support the picture tag. picturefill script Below is an example of the picture tag with different images specified. See how each image source has a media query similar to CSS media queries? Following mobile first, the image tag loads the smallest image first and then swaps it out on larger sizes (smallest to biggest from the bottom up). This will improve page load significantly on mobile because it loads an image at a pixel resolution suitable for its screen size. Plus it gives you way more control of how things look at different breakpoints. <picture><source srcset=”https://dummyimage.com/2000x400/007aeb/4196e5" media=”(min-width: 1400px)”><source srcset=”https://dummyimage.com/1400x400/007aeb/4196e5" media=”(min-width: 768px)”><source srcset=”https://dummyimage.com/800x400/007aeb/4196e5" media=”(min-width: 576px)”><img srcset=”https://dummyimage.com/600x400/007aeb/4196e5" alt=”responsive image” class=”d-block img-fluid”></picture> When setting up the image sizes and media size breakpoints, I referenced this list of . The second highest desktop screen size is 1920 x 1080 so I wanted to make sure i could cover that width without making the image blurry. So we are only going to load this if the image is greater than 1400px. Make the necessary adjustments based on your site analytics to target the most common screen resolutions. most common screen resolutions Looking good. The xs breakpoint is square and the xl is a wide rectangle. Maximizing the space and making the carousel more mobile friendly. | View Final Solution Demo Get code Things to watch out for Since you want your carousel to extend to the edges, keep your carousel outside of a or class because this applies left and right padding. .container .container-fluid Using the picture element for your images requires a lot more image editing in or similar software. If a creative change is made it will have to be applied to multiple image versions. So this will take more time. Adobe Photoshop Using placeholder images first can help figure out image sizes and breakpoints before you do any final image cropping. Summary In this tutorial you learned how to customize the carousel code snippet to use responsive images and go full width. This optimization achieves better load times on mobile and gives the designer control on how the images look at the various breakpoints. The only downsides are that it requires more image editing time and needs a polyfill to support IE11 and below. But in my opinion, the pros greatly outweigh the cons. The breakpoint preview screenshots used in this tutorial were created using Robin available in the . Bootstrap 4 Quick Start Get started learning responsive design basics step by step. If you enjoyed this story, please click the 👏 button and share to help others find it! Feel free to leave any questions below. Originally published at bootstrapcreative.com on June 27, 2017.

How to Build a Full Width Bootstrap 4 Responsive Carousel [Tutorial]

How I Grew My Instagram: Sharing My Journey as a Jewelry Designer

I currently run two profitable SaaS products, ResumeMaker.Online and aiCarousels.com. They serve different purposes, but there is some overlap (design-focused), and they share a lot of front-end and under-the-hood AI stuff. And although it has some cons, I couldn’t recommend this approach enough. First: platform risks. You build something on top of LinkedIn, Twitter, YouTube, or whatever platform that’s trending today, and you’re at their mercy. They change something, you’re screwed. Having two products has been my safety net. But this safety net has extra benefits. It keeps you level-headed. You’re not freaking out when a product churn spikes one month. You can make smarter decisions, not panic moves. You’ve got options. You can experiment, try things out, and not have to worry about ‘this product has to work or I’m screwed.’ I used to have a 9to5 job. It felt secure until it wasn’t. When I got fired, it was stressful AS HELL. I only had one product at the time, and I knew I couldn’t rely on just that. That’s why, after being let go, I decided to build aiCarousels, the first AI carousel generator (I documented the whole ride on YouTube). I’ve been running ResumeMaker.Online as well, which helps people create resumes, they’re different products, but because of the shared codebase, I can swap and improve features between the two easily. The big challenge is probably finding two products that can share a codebase. But even if they can’t share everything, at least sharing the front end is worth it. I’m not big on giving advice… I don’t know your personal goals, your market, or what you want out of this. But having two products lets me stay calm, make smarter decisions, and grow both without the constant fear of a single point of failure. Yes, there are some cons (splitting my focus makes me feel like neither product is getting enough attention or growth it could), but I would recommend you AT LEAST give it a thought. I currently run two profitable SaaS products, ResumeMaker.Online and aiCarousels.com . They serve different purposes, but there is some overlap (design-focused), and they share a lot of front-end and under-the-hood AI stuff. And although it has some cons, I couldn’t recommend this approach enough. ResumeMaker.Online aiCarousels.com First: platform risks. You build something on top of LinkedIn, Twitter, YouTube, or whatever platform that’s trending today, and you’re at their mercy. They change something, you’re screwed. Having two products has been my safety net. But this safety net has extra benefits. It keeps you level-headed. You’re not freaking out when a product churn spikes one month. You can make smarter decisions, not panic moves. You’ve got options. You can experiment, try things out, and not have to worry about ‘this product has to work or I’m screwed.’ I used to have a 9to5 job. It felt secure until it wasn’t. When I got fired, it was stressful AS HELL. I only had one product at the time, and I knew I couldn’t rely on just that. That’s why, after being let go, I decided to build aiCarousels, the first AI carousel generator (I documented the whole ride on YouTube). I’ve been running ResumeMaker.Online as well, which helps people create resumes, they’re different products, but because of the shared codebase, I can swap and improve features between the two easily. The big challenge is probably finding two products that can share a codebase. But even if they can’t share everything, at least sharing the front end is worth it. I’m not big on giving advice… I don’t know your personal goals, your market, or what you want out of this. But having two products lets me stay calm, make smarter decisions, and grow both without the constant fear of a single point of failure. Yes, there are some cons (splitting my focus makes me feel like neither product is getting enough attention or growth it could), but I would recommend you AT LEAST give it a thought.

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