Founder's Leap

The frightening moment when someone decides to take the plunge and go full-time on their own project, without a backup job.

Hi! Welcome to the Founder's Leap newsletter.

I’m JD, and like many others, I'm trying to start my own business.

This involves failing a lot and learning from these failures. This often happens without seeing the light at the end of the tunnel for a long time - it's been over a year for me.

Hearing about others' success helps shortcut this process. It also gives me motivation to keep going.

Founder's Leap is my way of sharing the knowledge from successful people.

It's for those who are forever with one foot out the door, yearning for the right moment to leave. It’s for the ones that are tired of making someone else money while moving their own needle. It’s for the ones who are about to quit.

They have made it, and so can you.

Today, in this first issue of Founder's Leap, we dive into the journey of Ruurtjan Pul. He is an entrepreneur who switched from a 9-to-5 job to running a successful set of web tools. Now, he also runs a course for developers.

Ruurtjan started WhatIsMyISP.com during his student days. He later made NSLookup.io and a DNS course for developers. His story teaches the steps of starting a side project and growing it to a full time job.

Find out his motivations, challenges, and the strategies he used. He took the Founder’s Leap from a secure job to a fulfilling entrepreneurial life.

What you will find today

• Founder’s card

• Background and current work

• Founder’s Leap and Monetization

• Growing as an entrepreneur

Founder’s card

Background and current work

Tell us about yourself, your background, and the path that led you to where you are today.

My name is Ruurtjan Pul, and I’m a full-time indie maker. I’ve always been interested in entrepreneurship, and since a young age, I’ve been interested in web development, building and running websites. It’s fascinating to me that you can push some buttons, and something suddenly exists, and people find and use it.

Since then I’ve built a small portfolio of web tools. You can see the tools I’ve built, which ones failed and why, and which ones succeeded, here.

Eventually, I quit my job to work on my tools full-time, and it paid off.

What are you working on at the moment?

I run two free web tools, and I’ve just finished recording my DNS for Developers course.

My oldest site is WhatIsMyISP.com. This started when I was a student, and I wanted to know what my university's internet provider was, but couldn't find a website that would tell me - only an API. So I decided to build my own with PHP and Bootstrap, just as a learning experience.

I was a bit hesitant to spend money for hosting and a domain name, as I wasn’t sure if anyone would use it, and I was about to let it expire a few times.

I’m glad I didn’t, because 10 years later, this tool only takes about one day of work per month and has grown to over 150,000 people who use it every month, and I have a partnership with NordVPN.

My main site right now is NSLookup - a DNS lookup tool that helps people inspect the configuration of domain names. I started it 3.5 years ago, and since the beginning, I had the goal of making a living from it. Two years ago, it started taking off, and that’s when I decided to quit my job.

Combined, the two tools get 750.000 unique visitors per month.

After years of experience in this area, I’m now launching a course that teaches DNS to Developers. It’s one of those technologies that devs will encounter (and fight) many times throughout their careers.

I think it pays off to learn it once and for all. Having a foundational understanding absolutely pays off in the long run. Websites, email configuration, and service discovery in Docker, K8s, and cloud providers all rely on it.

And it tends to break things every once in a while ;)

Founder’s Leap and Monetization

How long did it take you to earn the same you did from your job?

The second year of my business pretty much exactly equaled my most recent salary. This was mostly because the course sales added a big chunk on top of the ad revenue of my sites.

The nice thing was that they kept growing despite not working on them much during that time.

I know course sales tend to flatten out after a while, so I’ll need to keep growing my business to keep earning as much. But I’m confident I can make it happen. No need to go back to a regular job :)

Why did you decide you had to fully commit to your company - taking the Founder’s Leap?

I didn’t need to. I wanted to!

My sites could have slowly grown over time as I put in evenings and weekends. But I wanted to see faster growth and try entrepreneurship.

The timing was right, because we just got our mortgage (which is hard to do if you just started a business in the Netherlands), personal and professional growth flattened out at my day job, and my projects slowly started to take off.

This was it. My one chance at making it work. That’s not true of course - I could always try again, but that’s what it felt like.

What was the scariest moment on the whole journey since leaving “regular job”?

I’m quite risk-averse.

So I made sure I had a plan B (freelancing) and a plan C (getting a day job again).

I gave myself 12 months to try this, and had enough in the bank to survive that with my family.

The scariest thing for me wasn’t the leap itself, but whether or not I could make it work.

I felt a lot of self-imposed pressure to get to enough profit by the end of the year. Relying on SEO growth didn’t help. You tend to see results many months after you’ve invested in it. That was quite stressful.

Growing as an entrepreneur

What marketing channel was the most important for your growth?

SEO. My type of websites depends entirely on Google search, and this is bittersweet. It’s very hard to rank for competitive keywords, and it takes a long time to do so. But it’s amazing once the engine is running.

I’ve also started advertising on X for my course. Ads didn’t make sense for my sites, but now that I have something to sell, they turn out to be quite profitable.

Based on your experiences, what key piece of advice would you offer someone considering starting their own business?

I believe one of the most important keys to success is to strategically pick a side project. Having a long list of projects allowed me to choose the three most important criteria to evaluate an idea, and they are:

• Longevity — Will it stay relevant for a long time?

• The Monetization Sweet Spot — Can you make a living?

• Limited but Extensible Scope — Can you pull it off?

If you are thinking about going all in on a side project, I strongly recommend that you take a look at my blog post, where I examine each of these criteria more attentively: How to Pick a Side Project Strategically.

Where can people learn more about you and your products?

You can learn more about me and my products by visiting my personal website ruurtjan.com and my product websites nslookup.io and whatismyisp.com.

I’m @Ruurtjan on X.

If you are a developer wanting to learn more about DNS, we offer a specialized course at nslookup.io/dns-course.

Thank you for joining us in this first issue of Founder’s Leap, and a special thanks to Ruurtjan for telling us his amazing story. Reply to this email if you want to give me your feedback!

If you have a story to tell we would love to hear it! Fill out this form and we’ll get back to you.

See you in the next issue,

JD