Chaincode Labs BOSS 2025 — Cool Challenges, Tough Projects, Real Lessons

I’m a senior backend developer with programming experience since 2015, and I’ve been involved with Bitcoin and crypto since 2014. I left my full-time job in October last year and am currently on a break. In November, I started contributing to Bitcoin-related projects and came across Saving Satoshi, a game that helps people learn about the concepts behind Bitcoin. After completing the game, I joined their Discord to share feedback and was encouraged to apply to the Chaincode Labs BOSS 2025 program.

Application Process

Chaincode Labs is a well-known organization in the Bitcoin space and provides a wealth of learning resources for developers interested in Bitcoin. The Chaincode Labs BOSS program is an initiative aimed at onboarding more developers into Bitcoin open-source development.

Having already read through many Chaincode resources in the past, I decided to apply. The program was scheduled to run from January to April. The application process was simple and straightforward—you just had to fill out a form with basic details like your time zone, programming experience, preferred programming languages, etc. After that, applicants received a basic Bitcoin-related coding challenge on GitHub. Anyone with some coding experience could complete it quickly. Then, there was about a month of silence until I received my acceptance email at the end of December.

Programming Challenges

The program began with a series of programming challenges. The early ones were simple but became progressively more complex. According to the instructors, participants were expected to complete each challenge within 7 days. However, some participants finished them much faster—often in just 1–2 days—and were given the next challenge immediately.

The challenges covered a range of topics, including RPC commands, creating and signing raw transactions, and Lightning Network routing. Participants were encouraged not to use any Bitcoin-specific libraries beyond ECC/ECDSA libraries. The only allowed languages were C++, Python, and Rust, with Rust being encouraged for those unfamiliar with any.

Real World Projects

After completing the challenges, we were given a document listing real-world projects and were asked to pick one and contribute to it. I initially chose a project and joined its Discord to ask a few questions. I soon found out that the task wasn’t currently feasible due to a dependency on a specific library. So I picked a smaller and simpler project instead.

Due to some family issues, it took me a month to complete the task, which I finished around the end of March. I then picked another project—seeing that other participants were doing the same—but wasn’t able to complete it. There were weekly calls for those working on projects to discuss progress, share how they were feeling, and ask for help.

Seminars

At the end of February, the programming challenges were paused, and participants were invited to join the Bitcoin protocol development and Lightning protocol development seminar tracks. Participants were divided into groups, provided with reading material a week in advance, and given a question to present during a group call. Each participant was also paired with someone from another group who had the same question.

More details are available on the Chaincode Labs BOSS website. Those actively working on projects were advised to focus on their project work rather than join the seminars. I chose not to participate in the seminar programs.

Feedback

My main goal in joining the program was to connect with other Bitcoin developers and boost my confidence in my coding abilities. The first few weeks were excellent—the programming challenges were engaging and gave me a strong confidence boost, as I was able to complete them faster than most others.

However, during the project phase, I found the lack of structure a bit challenging. The project list didn’t include clear guidelines or instructions. After completing my first project, I also didn’t receive any feedback. The program instructor explained that this mirrors real-world open-source development: contributors often pick tasks with minimal guidance and may receive little to no feedback on their pull requests. While I understood that, the experience during the project phase felt a bit isolating, especially since I didn’t engage with the instructors much during March due to personal issues.

I felt more connected during the challenge phase than the project phase. The program officially ended in April. While it was slightly unfulfilling not to receive any kind of recognition for completing or attending the program, the experience itself was still valuable.

I’m considering reapplying next year and plan to be more proactive during the project phase.