In this interview, we sit down with Gabor Koos, the creator of Nullmail, to discuss their privacy-first approach to disposable emails. Nullmail offers instant, anonymous inboxes to help individuals protect their identities, avoid spam, and streamline account testing. Read on to learn how this open-source platform manages to deliver high utility while adhering to a strict zero-tracking philosophy. Nullmail What does Nullmail do? And why is now the time for it to exist? Nullmail is an open-source disposable email service that provides instant, anonymous inboxes with automatic expiry and zero tracking. It helps users protect their privacy, avoid spam, and quickly verify accounts without exposing their real email address. Built with a minimal, privacy-first architecture, it prioritizes usefulness over growth or data collection. Now’s a good time for Nullmail to exist because digital privacy concerns are at an all-time high, and users desperately need reliable tools to access web services without surrendering their personal data to aggressive tracking algorithms. What is your traction to date? How many people does Nullmail reach? Because the project is privacy-first and does not use analytics or tracking at all, exact user numbers are unavailable. However, roughly 10,000 disposable email addresses are generated monthly, indicating consistent active usage. Who does your Nullmail serve? What’s exciting about your users and customers? People who want to protect their privacy online, avoid spam during signups, and developers or testers who need temporary email inboxes for account verification and testing workflows. What technologies were used in the making of Nullmail? And why did you choose ones most essential to your techstack? Nullmail leverages a modern, lightweight tech stack built primarily on SvelteKit (TypeScript/JavaScript) for a fast frontend and server framework. We integrated Supabase for our backend services and storage, paired it with ForwardEmail to reliably handle the email infrastructure, and use Vercel for seamless deployment and hosting. What is traction to date for Nullmail? Around the web, who’s been noticing? Nullmail is currently experiencing solid organic traction, driven by users actively searching for privacy-centric temporary email solutions. Google Search Console reports approximately 2,000 monthly impressions and 500 clicks, which, when combined with the generation of around 10,000 inboxes each month, points to steady, real-world utility without the need for traditional marketing or invasive tracking. Nullmail scored a 76 proof of usefulness score (https://proofofusefulness.com/report/nullmail) - how do you feel about that? Needs reassessed or just right? https://proofofusefulness.com/report/nullmail I think it's broadly about right. Disposable email services are inherently useful because they solve a very concrete problem: protecting your real inbox from spam, trackers, and unwanted follow-ups when you just want to sign up for something quickly. Nullmail does exactly that in a simple and transparent way. At the same time, it's not trying to reinvent the category or become a full communication platform. It's intentionally minimal: generate an address, receive the mail, and move on. Because of that, a score in the mid-to-high range feels fair to me. It reflects that the tool is genuinely useful in practice, even if it's not aiming to be a massive, complex product. If anything, the score reinforces the idea that small, focused tools can still deliver real utility. What excites you about this Nullmail's potential usefulness? Most large disposable email services secretly collect data or require signups, undermining privacy. Nullmail provides instant, temporary inboxes without tracking, signups, or data collection. Its potential lies in offering a truly privacy-first, reliable alternative that solves real-world email needs safely and simply. Walk us through your most concrete evidence of usefulness. Not vanity metrics or projections - what's the one data point that proves people genuinely need what you've built? The strongest signal for me is that people occasionally donate through the Buy Me a Coffee button. Nullmail is completely free, there are no ads, and I don't track users in any way. So when someone voluntarily pays for something they could keep using for free, that's a pretty strong indicator that they found it genuinely useful. Beyond that, the only usage data I have comes from the database itself. Since I deliberately avoid analytics or tracking, the only measurable activity is the auto-incrementing IDs for created addresses and received emails. Those counters increase by several hundred to around a thousand per day, indicating that the service is actively used. Between those two signals - steady organic usage and occasional voluntary donations - I think it’s clear that the tool solves a real problem for people. How do you measure genuine user adoption versus "tourists" who sign up but never return? What's your retention story? In the traditional sense, I don't measure retention at all. Nullmail has no sign-ups, no accounts, and no tracking, so there's no concept of a "user" I can follow over time. That's actually intentional. Disposable email is a very transactional use case: you need an address for a quick signup or verification email, you receive the message, and you move on. In that sense, almost everyone is a "tourist", and that’s exactly how the product is supposed to work. Instead of retention metrics, the signal I look at is continuous usage. The steady creation of new addresses and incoming emails suggests that people repeatedly need a disposable inbox somewhere on the internet. Whether it's the same person returning or different people discovering the service, the ongoing activity indicates that the underlying problem is real and persistent. If we re-score your project in 12 months, which criterion will show the biggest improvement, and what are you doing right now to make that happen? The biggest improvement would probably be in long-term reliability and operational maturity rather than new features. Nullmail is intentionally a very small, focused tool, so I'm not planning to expand it into a larger product. The goal is to keep it simple and dependable. In practice that means maintaining the infrastructure and making sure the service continues to work as expected. For example, disposable email domains sometimes get blocked by services over time, so I monitor deliverability and rotate domains when necessary. I think usefulness for a tool like this is less about adding features and more about consistently doing one thing well: providing a disposable inbox that actually receives the email you're expecting. If the project is rescored in a year, the improvement I'd hope to show is that the service has continued running reliably and serving real usage over time. How Did You Hear About HackerNoon? Share With Us About Your Experience With HackerNoon. I actually heard about the competition because I was already publishing on HackerNoon. I've written a few technical articles there, mainly about practical engineering topics and data structures, so I was already familiar with the platform before the Proof of Usefulness competition. My experience with HackerNoon has been positive overall. I like that it focuses on long-form technical writing rather than short social posts, and that it gives independent developers a place to share detailed engineering work. The editorial process is also helpful to maintain a certain standard. Given that Nullmail processes roughly 10,000 generated inboxes a month without tracking analytics, how do you handle monitoring, abuse prevention, and infrastructure scaling? The service is intentionally very lightweight, so there isn't much to scale in the traditional sense. Disposable email is a fairly simple workload: generate an address, accept incoming mail, and display it. Even with around 10,000 generated inboxes per month, the infrastructure requirements are modest and run comfortably on a small setup. Monitoring is mostly operational rather than user-focused. I keep an eye on the health of the mail pipeline (whether messages are being received correctly) and the database growth. Since there are no user accounts or analytics, there's very little application-level telemetry by design. To keep the service reliable, a GitHub Action runs daily to check whether the email domain has been blacklisted. If it has, I rotate it and bring a new one online. Abuse prevention is also fairly limited by the nature of the service. Nullmail only receives emails, it does not send or relay outgoing messages, so it can't be used for spam campaigns or other outbound abuse. The main operational concern is domain reputation and deliverability. Overall, the philosophy is to keep the system simple: minimal moving parts, minimal data collection, and just enough operational oversight to ensure that emails continue to arrive reliably. With 500 organic clicks monthly, what is your strategy for growing Nullmail's search visibility against larger, albeit less private, disposable email competitors? Early on I promoted Nullmail on Reddit and Hacker News, but these days I don’t actively market it. The focus is on reliability, privacy, and simplicity. People who need a disposable inbox without tracking or ads find it organically, and that steady, quiet discovery is enough. Nullmail has faced and overcome challenges like domain flagging. What steps are you taking to ensure your disposable emails maintain high deliverability and continued usefulness for testing workflows? Daily automated checks: A GitHub Action runs each day to check whether the email domain is blacklisted or flagged, so I can respond quickly if something changes.Clear DNS hygiene: I keep DNS clean and correct with SPF, DMARC, and other recommended records, which makes the domain more trustworthy to receiving systems. Abuse contact and recovery plan: After the flagging incident, I added a dedicated abuse contact mailbox so that registries and providers have a point of contact if there’s ever a question about the service. Domain rotation readiness: Since disposable email domains sometimes get blocked simply because of how disposable services are perceived, I’m prepared to rotate domains when necessary so that emails keep flowing and testers can rely on Nullmail for workflows without disruption. Daily automated checks: A GitHub Action runs each day to check whether the email domain is blacklisted or flagged, so I can respond quickly if something changes. Daily automated checks: Clear DNS hygiene: I keep DNS clean and correct with SPF, DMARC, and other recommended records, which makes the domain more trustworthy to receiving systems. Clear DNS hygiene: Abuse contact and recovery plan: After the flagging incident, I added a dedicated abuse contact mailbox so that registries and providers have a point of contact if there’s ever a question about the service. Abuse contact and recovery plan: Domain rotation readiness: Since disposable email domains sometimes get blocked simply because of how disposable services are perceived, I’m prepared to rotate domains when necessary so that emails keep flowing and testers can rely on Nullmail for workflows without disruption. Domain rotation readiness:
