Introduction

Hey everyone! I’m Devi Charan, and I am writing this blog to share my journey on how I cracked Summer of Bitcoin 2025 . Trust me, it’s been quite a ride, from late-night coding sessions to those “aha!” moments when things finally clicked.

For SOB’25, I got selected to work on the “Extended message signing and verification using On chain addresses” project with Zeus, and I am soo thrilled about it!

Let me tell you a bit about myself first. I’m currently studying Computer Science at Scaler School of Technology, and I love building things with React, JavaScript, TypeScript, and Django. I’ve already worked at two startups as an intern, but what really gets me excited is open source, decentralization, and everything Bitcoin. I also love studying Operating systems and Networking.

Discovering Open Source

You know how they say every journey has a beginning? Well, mine started in my first year of college. Like most freshers, I was deep into DSA (Data Structures and Algorithms), thinking that’s all there was to becoming a good developer. But something felt missing. That’s when I realized that real-world coding is about building actual projects that people can use. So, I jumped into web development, starting with JavaScript.

The whole open-source world opened up to me when our college teachers introduced us to it. They mentioned programs like GSOC, and our open source club started hosting these super helpful sessions. But here’s where things got interesting — one of our instructors mentioned Summer of Bitcoin. I did some quick research, and honestly, it felt like finding a hidden treasure. I just knew I had to give it a shot.

My First Attempt: Rejection & Lessons

My first attempt at SOB wasn’t exactly a success story, but it taught me a lot! They kicked things off with this amazing one-month bootcamp where we dove deep into blockchain, Bitcoin, and decentralization. I was completely hooked! But then came the real challenge that would keep me up at night mining a block from a mempool.

Here’s the thing, Bitcoin transactions aren’t just simple transfers. Each type like P2PKH, P2SH, or SegWit comes with its own structure and rules. Understanding and validating them programmatically is not an easy task. After verifying each transaction, you need to mine a block, create something called a merkle root, handle coinbase transaction, and deal with witness commitment. I know, it sounds like a mouthful, right? At that time, I was just getting started with basic projects, and trying to understand all these concepts, let alone combining them into working code, felt like trying to solve a Rubik’s cube blindfolded!

Those 25 days were some of the most intense of my life. The code just wouldn’t work, and I was about to quit. Thank goodness for my friend (who’s also my classmate), together we finally got it working. Looking back, it’s crazy to think how something that seemed impossible then would become manageable a year later.

I made it to the proposal round that year and, being comfortable with JavaScript and React, I thought Zeus would be the perfect fit. The project was about integrating CLN REST APIs into their codebase. But here’s where I messed up, I spent too much time learning about things, setting up the dev environment, getting used to it and not enough time actually implementing them. Result? I got rejected. Yeah, it stung a bit, but you know what? That rejection turned out to be a blessing in disguise. It made me look hard at what I needed to improve, and those improvements helped me land my first internship at a startup by the end of my first year.

SOB 2025: New Format, New Me

Fast forward to this year, and SOB came with a whole new format. Four assignments in four weeks, each one building on the last. Miss one week, and you’re out. No pressure, right? 😅 But here’s where all that previous struggle paid off. The first assignment? Building a basic Bitcoin transaction that sent 100 BTC with a message “We are all Satoshi!!” embedded in the blockchain. I knocked that one out in just a day, what a confidence boost!

The second week brought us into multisig territory with P2SH-P2WSH addresses (I promise these aren’t just random letters!). It was definitely trickier, and took me about 2–3 days to figure out. But then came week three, the block mining challenge. You know what’s funny? It was almost identical to the assignment that had me pulling my hair out the previous year. But this time around, even though it was still challenging, I could actually see the path forward. Sure, I still struggled trying to fit transactions into a block while following Bitcoin’s rules, but I managed to solve it in about a week. It felt like clear proof of growth.

Looking at these two experiences side by side really showed me how far I’d come. The same challenge that once had me sleeping only 4–5 hours a night for weeks was now something I could tackle with much more confidence. Don’t get me wrong, it wasn’t exactly easy this time either, but at least I wasn’t questioning my life choices at 3 AM anymore! 😄

Proposal Chaos and Acceptance

After conquering all those assignments, I was ready for the next challenge. I headed straight to Zeus to check out their project ideas. Two of them really caught my eye: “View connected and disconnected peers in Zeus” and “Extending Message Signing & Verification with On-Chain Address Keys”. But when I joined the Zeus community, I got hit with this wave of FOMO (Fear of Missing Out). There were already participants, raising PRs and even giving demos! Someone had already started working on that peers project I was interested in.

But then I noticed something interesting, nobody was touching the Extended message signing project. It was like finding an unopened present. I didn’t think twice, I jumped right in. First things first, I dove into research mode, learning everything I could about Bitcoin RPCs and APIs that could help build this thing. You know that feeling when you’re so excited about something that you can’t wait to start? That was me! I got my dev environment set up faster and started coding away.

I managed to put together a quick demo and raised a PR. The implementation wasn’t perfect, but it was pretty close to what they were looking for. Here’s the thing though — I knew one PR wasn’t enough to show what I could really do. So I started hunting for other issues to work on and found some, fixed them, and got those PRs merged. But I never took my eyes off that message signing project, I integrated backends for different types of node implementations and made the UI better !

Now, here’s where things get a bit funny (or scary, depending on how you look at it). I was so caught up in building and coding that I completely forgot about writing the actual proposal! When it hit me, I had just 4 days left before the deadline. Talk about a panic moment! I was sitting there, staring at my screen, wondering how on earth I was going to turn all my work into a proper proposal. I spent an entire day just reading through successful proposals from alumni (thank goodness for those!), picked up some ideas from 2–3 of them, and finally wrote mine.

https://guide.summerofbitcoin.org/the-proposal-round/writing-a-winning- project-proposal _
You can refer this page for writing a good proposal and example proposals._

Then came the waiting game. You know that feeling when you’re both super confident and totally nervous at the same time? That was exactly my state of mind. I knew I’d put in the work, but there was some serious competition out there.

When the results finally came in… I GOT SELECTED! I literally couldn’t believe my eyes! All those late nights and debugging sessions had finally paid off. My mentors at Zeus, Evan and Shubham, sent their congratulations, and I had my first meeting scheduled. I’ll be honest — I was terrified it would be like an intense technical interview, so I crammed all this Bitcoin stuff the night before. But guess what? It turned out to be this really chill conversation about getting to know each other. He even went through my PRs and tech profiles and gave me some really helpful feedback.

Building with Zeus: Real Contributions

I’m still working on the Extended message signing and Verification project, which is almost wrapped up. But the cool part is, I’ve also taken on another exciting challenge: “Circular Rebalance of Channels”. Both these features are pretty awesome and should make life easier for Zeus users. It’s amazing to think how far I’ve come from those sleepless nights trying to figure out my first Bitcoin transaction!

Key Takeaways from My Journey:

You know what’s funny about open source? It’s not just about writing code, it’s about having conversations! One of the biggest lessons I learned is that communication is absolutely key. Don’t be afraid to speak up, share your ideas, and talk to your mentors. They’re there to help, not to judge!

When it comes to picking projects, here’s a golden rule I discovered: choose something that makes you excited to jump out of bed in the morning. It is important to make sure it’s something you can actually build. There’s no point in promising to build a rocket if you’re still learning to ride a bike!

Here’s something that might surprise you, you don’t need to know everything! I used to think I had to be some kind of Bitcoin genius before I could contribute. But that’s not true at all. What matters is being honest about what you know and being eager to learn what you don’t. Speaking of which, don’t try to bluff in your proposals.

The real secret sauce? Consistency. Keep that initial excitement burning even when things get tough. It’s like a marathon, not a sprint. Also, remember that everyone started somewhere. Even the most experienced developers were beginners once.

Looking Forward:

I’m currently wrapping up both features I’ve been working on, but I’m not stopping there! I’ve found some interesting feature requests that could improve the Zeus app for users. You know that feeling when you use an app and think “I wish it could do this…”? Well, now I get to be the person who makes those wishes come true!

I’m committed to keeping up with our weekly check-ins , they’ve been incredibly valuable. There’s nothing quite like getting honest, sometimes brutal feedback to help you grow. Here’s the cool part, even after the program ends, I plan to keep contributing. This isn’t just a summer thing for me anymore; it’s become part of who I am as a developer.

For Future SOB Aspirants:

If you’re reading this and dreaming about cracking SOB yourself, I’ve got your back! Here are some resources that were absolute gold for me:

1. Learn Me a Bitcoin: This site breaks down complex Bitcoin concepts into bite-sized pieces that actually make sense.
2. The Bitcoin Whitepaper : Yes, it looks intimidating at first, but it’s like the Bitcoin bible. Take your time with it.
3. Grokking Bitcoin :This book was a game-changer for understanding the technical stuff.
4. BIPs (Bitcoin Improvement Proposals) : These are great for understanding how Bitcoin evolves and improves.

<https://spiral-yumberry-b12.notion.site/Extending-Message-Signing- Verification-with-On-Chain-Address-Keys-1ded49f2da38805184e8e6758346d344>

Here is the link to my proposal.

Remember, everyone’s journey is different, but I hope sharing mine helps light the way for yours. The Bitcoin community is amazing, and there’s always room for more passionate developers who want to make a difference!