The year 2025 is coming to an end and did it go fast! It feels like the way we develop has been changing faster than ever. I’m constantly reinventing myself, learning new techniques, and letting go of old patterns. It’s been a year with many milestones, but also the first year in which I’ve been fully independent.
It’s time to look back at the milestones that crafted my successes. I’ll also have a look into what’s next and reflect on how I’m reshaping my way of approaching app development.
A full year as an indie developer
March 2024, I decided to go fully independent. I officially left WeTranfser at the end of July 2024, even though I primarily worked on personal projects since March. Either way, this year has been the first one where I fully focused on indie projects only.
And yes, I can tell the impact. Revenue numbers aren’t fully available yet, but I more than doubled my business income already. I continued to grow existing projects like SwiftLee Weekly and RocketSim, but also had to let go of lower potential ones. The Going Indie podcast was fun to do, but turned out to not be successful enough to focus on.
Time flies when you’re having fun! I’ve spent much more time with my family and I could constantly decide myself what to work on. The colleague I’ve seen the most has been my dog, but it’s not that I’ve been lonely. Many friends from the community went indie as well, I’ve got a constant connection with many of them.
Altogether, I can’t imagine myself working for a company anymore. It simply limits my creativity, it forces me into boxes. I’m sure not every company is like that, but the freedom of switching gears quickly and embracing growth constantly is just unmatched.
Launching my first coding-focused course: Swift Concurrency
One of the things I haven’t been able to do while working at a company was launching courses. It’s time-consuming, even though I knew I had all the skills to do it. I know how to write articles, I know how to explain complex topics in an easy-to-digest manner.
One of my biggest goals for 2025 was to launch a coding course. I already launched my www.going-indie.com, but it was focused on a niche audience. At the same time, I was highly skilled in Swift Concurrency, and it’s been a year full of concurrency announcements. It became a perfect marriage, and I pre-launched the first modules in March 2025 at www.swiftconcurrencycourse.com.
I expected a coding course to do great, as I already have a large following of developers who should all be interested in learning about Swift Concurrency. The course now offers 70+ lessons across 11 modules and has been completed by over a thousand engineers. That’s excluding several teams like Airbnb, Garmin, and Monzo. Responses have been fantastic, and every week, new students post their certificate of completion on their LinkedIn.
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RocketSim for Teams: beating all expectations
What’s been one of the biggest surprises is the success of RocketSim for Teams. I started a new ventures together with two friends (frontender & sales expert) in November 2024. We decided to join forces and bring RocketSim for Teams to life (basically the b2b part). The first version went live in December 2024, mostly focused on enhanced team seats management, license management, but also build insights.
I remember me, Ralph, and Niek, setting a financial Monthly Recurring Revenue goal for the year of 21K. That would be a fantastic goal to work towards to. Not realizing 2 months later in February that we needed a new financial goal, ha!
Growth continued, with one of our biggest milestones during WWDC. Ralph and I went to the Meta head office and presented RocketSim for Teams:
It’s been one of the few companies we’ve visited that week. We also hosted a RocketSim WWDC party and connected with several Apple engineers to set the direction for RocketSim going forward.
Overall, we welcomed 250+ teams to RocketSim, and we’ve only seen a handful of teams not renewing their Gumroad license yet. With new features like Simulator Camera and advanced Simulator recordings, several significant improvements were introduced into our developer tool.
How AI is driving me out of my comfort zone
It’s also been a year of adopting AI for development. It’s insane how fast these tools improve, and as engineers, we have to keep up. I’ve been developing apps since 2009 and I’ve created a certain habit of how I like to build sustainable apps. Yet, it feels like I’m driving myself out of that comfort zone, letting go of certain principles.
Especially for the new app I’m building for my YouTube Series, From Side Project to 10K MRR, I’m finding new ways of development. Instead of crafting code carefully, I’m now running AI agents in parallel to create ideas instantly. If a proof of concept doesn’t work, I revert the changes and start over. Every now and then, I’m revisiting the code that’s here to stay, making it as solid as possible.
It feels like I’m reinventing myself. I’m trying to find new ways of making AI agent output better. I craft high-quality guidelines inside my AGENTS.md file, and I’m embracing SwiftLint and SwiftFormat like never before. Giving agents eyes has been a constant mindset over the past weeks and I feel like it’s becoming even more important for the coming months.
Blog article readers are going down
That AI is growing is not only visible from the development work I do. I can also tell that blog visits are going down. Well, some visits are going up (looking at you, AI crawlers), but those are not the ones that make blogs successful.
It’s a problem in the space — AI is killing its own sources. However, it’s hard to prevent. Why would you go to Google, search for an article manually, and read it carefully to just find a single answer that AI can give you instantly?
These numbers going down are painful for me as a blog writer, but it’s inevitable. I’m honestly afraid it will eventually even lead to me publishing fewer in-depth articles, since it’s not bringing as much value in return anymore.
Shifting my focus to YouTube
That’s also why I’m slowly shifting focus to YouTube. It’s offering a different way of learning, targeting a different audience. My courses did very well in 2025, so well that I’ve been asked to join an accelerator program with the course platform. They told me all big courses have one thing in common: they’re on YouTube. And it makes sense, if you think about it! YouTube is full of educational content, and it’s a great way to connect with a teacher personally. If you like one’s videos, you’re more likely to continue through their courses.
What also helps is that YouTube is growing rapidly, and AI is not easily hijacking views as much as it takes away readers. At least, that’s my assumption. It also helps that I like creating videos, and it feels natural to me. How this evolves exactly is uncertain yet, but the first published videos have been doing great. (feel free to subscribe to my channel)
The newsletter shows higher growth than ever before
The one thing that’s consistent has been my newsletter. Or well, it’s actually doing better than ever before. Growth accelerated since October, and I’m now also sending it out via LinkedIn. Altogheter, I’m reaching 30,000+ developers every single Tuesday.
With AI hijacking blog reads, newsletters are even more critical for discovery. Sponsors leverage this reach, and I also help fellow writers consistently reach new readers for their content. The newsletter evolved quite a bit this year, with the “What I’m working on” section being the most prominent new addition.
What’s next for 2026?
I traditionally start my in-depth planning for each year in January, but I can already look ahead to what I think 2026 will bring.
Let me start by saying that I’ll continue writing weekly articles, my weekly newsletter, and RocketSim development. I’m also working on two new collaborations for new courses. I’ll be giving talks in Amsterdam, Skopje, and maybe two more locations later in the year.
RocketSim’s focus will shift towards two major themes: AI (I’m currently looking into MCP support), and one that’s a bit more secret. We’re expecting a big year for RocketSim, as app development is changing rapidly.
Personally, I want to evolve my business into a multi-app one. I’ve already started development for a new customer-facing app (watch more about it here), and I’m sure I’ll start another one throughout the year. My development speed has been accelerating so much over the last few months, that I can’t imagine what milestones can be achieved by further optimizing my workflows.
Thank you!
I want to close by thanking you for your continuous support. I’ve meet several of you in person at conferences throughout the year, and many of your reached out digitally to share your appreciations. Without your support, SwiftLee’s year would not have been such a success.
I wish you all the best for 2026 and a happpy new year!