Arbitrum has activated its ArbOS 61 “Elara” upgrade, adding new tooling for Orbit chains, including an optional protocol-level compliance filtering feature for enterprise deployments.
The upgrade went live on August 20. Node operators are required to update to Nitro v3.11.3. Elara also expands the Stylus contract size limit from 24 KB to 96 KB, giving developers more room for larger smart contracts.
The compliance filter will likely attract the most attention.
But the key word is “optional.”
The feature is designed for private or enterprise Orbit chain operators. It should not be described as censorship on public Arbitrum One or Nova networks.
TL;DR
- Arbitrum activated the ArbOS 61 “Elara” upgrade.
- The upgrade adds optional compliance filters for Orbit chains.
- Stylus contract size limits expand from 24 KB to 96 KB.
Why Elara Matters
Arbitrum is no longer just one L2.
The ecosystem includes Arbitrum One, Nova, and a growing Orbit chain framework that lets teams launch custom chains using Arbitrum technology. That means upgrades increasingly affect not only public users, but also teams building specialized networks.
Elara fits that broader direction.
It adds capabilities aimed at developers and enterprise operators, while continuing to refine Arbitrum’s infrastructure stack.
For Orbit chains, customization is the pitch. Teams can design chains for specific use cases, compliance needs, performance goals, or application environments.
Compliance Filters Will Be Debated
The optional compliance filtering feature is likely to divide opinion.
Enterprise and regulated users may see it as necessary infrastructure. If a private Orbit chain is serving institutions, tokenized assets, or regulated workflows, operators may need tools to meet legal and compliance obligations.
Crypto purists may dislike the idea of filtering at the protocol level.
Both reactions are understandable.
The important point is scope. The feature is not described as a blanket change to public Arbitrum One activity. It is configuration-dependent and aimed at Orbit chain operators.
That distinction matters for users worried about censorship.
Stylus Contract Expansion Helps Developers
The Stylus contract size increase is also important.
Moving the limit from 24 KB to 96 KB gives developers more flexibility when building larger or more complex contracts. That can support richer applications and make migration easier for teams with heavier codebases.
Stylus is one of Arbitrum’s major developer-facing bets.
It allows smart contracts to be written in languages beyond Solidity, opening the door to Rust, C, and C++ developers. Expanding contract size helps make that environment more practical.
Orbit Is Becoming More Enterprise-Friendly
Elara shows Arbitrum leaning further into customizable infrastructure.
Enterprise adoption often requires controls that open public networks do not prioritize. That can include permissioning, compliance tooling, custom gas models, privacy considerations, and operational control.
Orbit chains are designed to serve those needs.
The challenge is maintaining a balance between enterprise flexibility and crypto’s open-network ethos.
Arbitrum’s approach appears to be letting custom chain operators choose features without forcing the same rules across the public ecosystem.
What Comes Next
The next test is adoption.
If more teams launch Orbit chains using Elara’s new capabilities, the upgrade could strengthen Arbitrum’s position in the rollup-as-a-service and enterprise L3 market. If the compliance tooling remains niche, the developer improvements may matter more than the regulatory features.
Either way, ArbOS 61 is a notable infrastructure upgrade.
It shows Arbitrum continuing to build beyond a single public rollup and toward a broader stack for custom Ethereum-aligned chains.
This article is based on Arbitrum and Offchain Labs materials for the ArbOS 61 “Elara” upgrade.
This article was written by the News Desk and edited by Samuel Rae.
This report is based on information released in disclosures at primary source documentation.
