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500,000 users per month after quitting his developer job

500,000 users a month after quitting his job

Today's interview is with Ruurtjan, a Dutch founder whose two sites get 500,000 users per month. Ruurtjan quit his job to go all in on his business and you can learn how he is progressing as an entrepreneur in this chat we had. Edit: Ruurtjan now has a course out, DNS for Developers (affiliate) where you can learn about domains, protocols and much more.


Can you tell us about why you started NSLookup and What is my ISP?

It all started back when I was a student. I remember wondering what internet provider my university was using. After some searching, I found an API that offers this information, but no single-purpose website. So I decided to make one with PHP and Bootstrap and put it live without much thought. More of a learning experience than a deliberate plan to start a business, if anything.

Fast-forward 10 years, and it has slowly grown to a tool that is used by about 150,000 people every month. Since its inception, I've moved from whoismyisp.org to whatismyisp.com, and partnered with NordVPN. It now keeps running with about one day of work per month.

WhatisMyISP screenshot

NsLookup was a different story. I started it two and half years ago with the goal of making a living from it. This site helps people inspect the configuration of domain names. This data is stored in the DNS and is publicly available to anyone using command line tools. NsLookup makes it easier to navigate and adds additional information to debug DNS issues.

When it started to take off after about a year, I decided to quit my job to focus on these projects. Now that I'm working full-time on them for a bit over a year, I'm getting close to replacing my previous income with them.

NS lookup io screenshot of Twitter

What have been your biggest achievements so far?

That would be the fact that I dared to give up stability to take the leap into the unknown. I didn't know anything about entrepreneurship, accounting, marketing and sales when I started. In fact, growth in these areas was one of the main reasons I decided to go for it.

Other than that, it still blows my mind that about half a million people use whatismyisp.com and nslookup.io. That's one in every 16,000 people alive today 🤯 It’s crazy to me that something I made helps that many people, even if it’s just a tiny bit.

How have you monetized your sites?

I started out with Google Adsense on whatismyisp. When it grew to around $600 / month, I decided it would be worth my time to optimize this. After reaching out to a couple of VPN providers, NordVPN was willing to run a paid trial with me. We’ve kept running month-long A/B-tests to optimize the ad placement and messaging ever since.

NsLookup.io started out without ads. After about eight month, I’ve added Carbon Ads by BuySellAds. They’re great to monetize content with very unintrusive ads. They also don’t track, so you don’t need a cookie wall with them.

More recently, I’ve switched to Google Ads to try to improve monetization. This didn’t improve things at all, to my surprise… So I kept searching and ended up with NitroPay. This about doubled my ad revenue to the point that I’m almost able to live off my projects.

Ad revenue depends on many factors, like where your visitors live, the type of work they do, how long they are on your site, the ad placement, etc. So be sure to test out different ad partners and don’t take Twitter glory shots as facts.

What have been your best marketing channels?

Search. By far. My type of website depends almost completely on Google. It’s a liability for sure, but it can also give a steady stream of traffic without much maintenance. It requires significant effort to rank for competitive keywords, and it takes many months for things to ramp up. But once it gets going… Oh, man!

Google search console chart showing 1.87 million clicks

What's your stack?

I’m a software engineer by trait, so I tend to overcomplicate things. I sure have for NsLookup. To be fair, though, part of the reason I chose this stack is that I enjoy working with it, and wanted to get better at those technologies.

The frontend of NsLookup is built with Typescript and Vue. The backend is Scala 3, ZIO and quite a number of dependencies. A bit overkill perhaps, but it does works nicely with all the async network calls. Being able to construct an execution graph with error handling and timeouts wouldn’t nearly be as easy with other setups. So pro’s and con’s I guess.

I host NsLookup on three cheap VPS’s around the world, with Cloudflare’s geo-loadbalancer and CDN in front. That way static files are instant, and lookups don’t have to travel far. The deployment is a bit more complex, but the payoff is a lightning fast site with no downtime during deployments and single server crashes.

Whatismyisp.com is a lot simpler with a single VPS running PHP. Not much fancy there, but I’m happy with the setup as it served me well all these years.

Do you have tips for people who have quit their jobs to work on their idea?

I’ve actually written a full blog post on this: How to pick a side project strategically.
In general I’d say, pick something that can grow over time, and be patient. Very patient, unfortunately 😉

twitter ghost writer

What does an average day look like for you?

I stick with 9 to 5 to keep work and private life separated as much as possible. I’m either in work mode or not. No midnight coding sessions for me. They can be fun and exciting, but I believe that slow and steady wins the race. I’d rather have a sustainable pace than go fast and risk burnout or get bored when the initial excitement wears off.

The great thing about being an indie maker is that you can take a day off any time, or go for an hour long walk while listening to a podcast. I sure do take these liberties.

Most days I start with some admin tasks like email (and checking statistics, which I know is mostly futile 🙈). Then, depending on what I’m working on, I’ll pick a task and try to make progress on that.

Planning my tasks for the month works well for me. I’ll take some time to think about what I’d like to work on and label them in Todoist. This makes it easier to be deliberate when working, instead of doing random things and being all over the place.

Another thing that works well for me is working in sessions of 35 minutes. It’s enough time to get deep into it, while being short enough to avoid procrastinating. I take 5-minute breaks in between and then go again.

Who are your favorite founders that inspire you?

I love learning about makers like Quentin Tarantino, MrBeast and Adam Savage (known from Myth Busters). The way they obsess about their craft, and design their life and workspace to fit their way of making inspires me. I think it’s really cool to see the passion they pour into their work. Here’s a YouTube playlist of interviews with makers if this is the kind of thing you also enjoy.

Where can people find out more about you?

I’m @Ruurtjan on Twitter. If you have any time to spare, please check out nslookup.io and DM me anything you think I should improve. I’m always trying to improve it, and I’d love to meet fellow (aspiring) makers!

Edit: Ruurtjan now has a course out, DNS for Developers (affiliate) where you can learn about domains, protocols and much more

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