Stylus is ready for production on Arbitrum One. The 24 KB number is in the docs. The gate you actually design for is one fragment. That is the difference between a green check and a live user.
This is Part 4: not a fourth Mini-App. It is what generalized once the first three were live on Arbitrum. A DEX aggregator inside Lemon. A randomness pattern against live Chainlink VRF. A USDC vault split across Aave, Morpho, Fluid, and Euler. Stylus handled the workload. These are the production patterns that made the deploys stick.
Three things to know before you ship on Arbitrum One
1. Check against Arbitrum One, not only Sepolia. Arbitrum One’s ArbOS has no multi-fragment support. Sepolia’s does. The same 2-fragment core exited 0 against Sepolia and reverted against One. Point CI at One, and the binary you activate is the binary you tested.
2. Pin gas on Stylus→EVM calls. eth_estimateGas can under-report a Stylus call into a live protocol. Two Arbitrum One transactions mined out-of-gas at the estimator’s limit, then succeeded on retry using less gas than that limit. It looks like a contract bug. It is the estimator. Production clients pin 6,000,000. Unused gas refunds on Arbitrum, so the headroom is cheap insurance.
3. Validate against live protocol state. There is no full fork-test against live L2 state yet. Small real-USDC round-trips on Arbitrum One are how we confirmed Aave, Morpho, Fluid, and Euler would take the call. That is the path that ships.
One more size lever, because it is the one that actually moves the needle: -Cpanic=immediate-abort plus -Zbuild-std reclaimed ~9.9 KB. Relocating features reclaimed ~2.1 KB. Pull panic first, and you stay under the fragment gate.
The production report is public. Architecture, addresses, gas tables, and notes we sent the Stylus team are in the open write-up. Use it on the next deploy.
The three apps, live
BananitaSwap
USDC↔token swap through Camelot and Uniswap V3. Stylus router, sitting inside Lemon, live on Arbitrum One.
- DEX
- Mainnet
- Lemon
CoinFlip
Asynchronous randomness: Stylus core, Chainlink VRF v2.5, locked liability, permissionless refund. The pattern, not the toy.
- VRF
- Solvency
- Open source
Vaulty
One USDC deposit, split across Aave, Morpho, Fluid, and Euler. Live on Arbitrum One since 10 August 2026.
- ERC-4626
- Mainnet
- USDC
Shipping Stylus on Arbitrum this quarter? We already ran this path. Book 30 minutes.
About WakeUp Labs
We build production systems for finance and infrastructure. New runtimes only prove themselves under real constraints: real users, real protocols, real gas. That is the work. If you want Stylus in production on Arbitrum, talk to us.