RIP BOZO, Devconnect Buenos Aires Stylus meetup by WakeUp Labs
7th December 2025
Hello everyone! I hope late December is treating you well. We’ve been away for so long, I’ve been busy doing development on Orderbookkit, and we have a deficit of posts in the newsletter at this moment. In this week:
Devconnect Argentina happened! It was amazing. WakeUp Labs organised a fantastic get together for the community, and yours truly was there! Let’s discuss.
Announcing RIP BOZO: A production app show and tell for bobcat-sdk. Deposit more than the last user, and be the last Bozo standing to win the prize pool! Including a silly little video.
Read on, and as always, if you have any feedback, please share it here:
To recap, Stylus is a Arbitrum technology for building smart contracts in Rust, Typescript, Zig, and C. Stylus lets you build smart contracts that are 10-50x more gas effective than Solidity smart contracts.
Devconnect Argentina recap
Devconnect Argentina happened! I headed there to give a talk on the history of Stylus including it’s on-chain penetration. Unfortunately, on the flight over, I got sick and lost my voice, so we gave my talk a miss. Thankfully Jess and the WakeUp Labs team were very forgiving. At their Stylus event, there were several speakers, including:
Peyman, co-founder of Fairblock spoke about Fairblock’s on-chain confidentiality with Stylus. Fairblock are super contributors to the ecosystem!
Srinjoy, product manager at Offchain Labs managing Stylus, reflected on the adoption of Stylus, what’s working, and what’s next.
Sergio, co-founder of Fairgate discussed smart contract execution on Bitcoin, and how Stylus uniquely enables the sidecar that’s needed using Arbitrum and BitVMX. This was a very engaging talk!
Milton, co-founder of WakeUp Labs spoke at length about their AssemblyScript (TypeScript) to Stylus compiler. We covered this in a previous post!
The rest of the event was nice, it was great to meet so many contributors from the space.
At Arbitrum Day, the mood was electric. It was great to name so many faces! WakeUp Labs spoke at a panel on Stylus, which was really great.
My talk will make a reappearance in the future at another venue, and in a recorded video for WakeUp Labs to distribute. We’re really lucky to be a part of the ecosystem, and Arbitrum at large!
Announcing RIP BOZO
RIP BOZO is a defi game of chicken where the rules are simple: be the last to deposit when the time runs out, and win everyone’s deposits. I developed this as a fun little show and tell for bobcat-sdk, and it lives fully open source in the examples directory. The code includes the graph that takes comments, the webapp, and the contract code. The game is powered by USND, the stablecoin by Nerite by CupOJoseph, a decentralised algorithmic stablecoin for the Arbitrum ecosystem.
I vibecoded the frontend with Codex after making the frontend in Figma. Each match lasts 45 minutes, with the last depositor to a growing prize pool that can only be added to if the amount exceeds 110% of the last deposit winning. The contract, despite reverting with an actual stack trace when a revert happens (using Error(string)) is only 30kb. Cool!
I’m developing this project in collaboration with Ivan of Superposition. We’ll have socials and a points program soon! The app is live on Farcaster, and we’re adding support for using Relay to buy from another chain virtually instantly into USND and a position.
The source code includes the entire webapp, the graph code, and more. It also includes the crank script that automatically resets the game and supplies it with randomness.
bobcat-panic
bobcat-panic is a crate with multiple panic-related features to make Stylus development simpler and safer. Enabling it with no_std and the feature panic, it supports the following flags:
panic-revert: On panic, print the full panic message. This is usually an explanation (if you were to use assert! for example), and the line that the error took place. Super helpful for understanding why something broke down.panic-loc: On panic, print the filename and line that the issue took place in.panic-trace: On panic, print the last register of a transient storage slot that was written to, decoding a string or number that was written there.
RIP BOZO actually uses panic-revert, and it falls under codesize anyway!
Testing with Forge Foundry (arbos-foundry)
The testing code was developed in collaboration with Bernard of the arbos-foundry team, so the end-to-end tests are a good example of how to use arbos-foundry to test your code.
The tests in the broader bobcat-sdk repo include fuzzing, with this example being testing an exotic permissionless upgradeable proxy, which we titled the metamorphic migration pattern. This is such a great tool for testing Stylus contracts in the real world!
Stylus Saturdays is brought to you by… the Arbitrum DAO! With a grant from the Fund the Stylus Sprint program. You can learn more about Arbitrum grants here: https://arbitrum.foundation/grants
Follow me on X: @baygeeth and on Farcaster!
I develop Superposition, a defi-first chain that pays you to use it. You can check our ecosystem of dapps at https://superposition.so.
