Case study · Arbitrum
A coding assistant that only claims what it can verify
During the Arbitrum Stylus Sprint, FairAI and EmberAI built Sifter, an assistant for developers writing Arbitrum Stylus contracts in Rust. It cites a source for every claim and, in the editor, compiles the code it suggests before calling it good.
Question
What’s the current tooling for testing Stylus contracts?
Sifter
Here are current tools for building and testing Stylus contracts: the Stylus Playground for building, compiling, and testing in the browser; Foundry and Anvil integrations for Solidity-plus-Stylus testing workflows; stylus-toolkit for primitives and examples; and the Welldone Studio Remix plugin to write and deploy. For the full picture, the official Stylus docs and Awesome Stylus — plus the stylus-sdk-rs testing PRs #365 and #416.
Sources
About the client
Arbitrum is a network that runs on top of Ethereum. With Stylus, contracts can be written in Rust as well as Solidity. Sifter is an independent tool for developers building on it.
The challenge
Stylus is young: the docs, the SDK and the repos change week to week. Generic AI assistants invent functions that don’t exist and hand over code that doesn’t compile, and developers lose hours checking everything.
What we built
- Answers with sources: every claim links to the doc, repo or code change it comes from
- A knowledge base that refreshes itself and knows the SDK version: what went stale is pushed down
- Compiler verification: the code the assistant writes is compiled and fixed until it builds, within the network’s size limit
- A score for each Solidity contract: from 0 to 100, how much it gains from moving to Rust, and why
- Security review and deployment to the network, step by step, never printing the keys
- Every answer can be rated, and well-rated answers are reused in the next ones
- Open source, with a web chat, an editor install (Claude Code, Codex) and an MCP server
Today
Sifter is published as open source, with a web chat, an editor install and an MCP server.
The first project for Arbitrum
An assistant on the funded projects’ proposals
In 2024, for Arbitrum’s incentive programmes (LTIPP and STIP), FairAI built an assistant that reads the funded projects’ proposals and answers questions about them: how many there are, what each one does, how they will use the funds. It was delivered in milestones, each approved by the programme lead.
“…pretty satisfied of the results despite being a complex project requiring a lot of coordinatio[n].”Question
How many projects are participating in the LTIPP program?
Projects Discoverer
According to the provided text, there are 82 protocols listed below that have had their streams initiated by the LTIPP multisig.
Question
Can you give me more information about Clipper?
Projects Discoverer
As for your request to provide more information about Clipper, I can summarize the key points:
- Clipper is a decentralized exchange (DEX) designed specifically for blue-chip token swaps.
- It aims to provide a seamless trading experience with no impermanent loss for liquidity providers (LPs).
- Clipper incorporates prices formed off-chain into a sophisticated formula and validates them on-chain, removing the need for arbitrageurs and ensuring lower gas fees for traders.