Today while researching L2, I found that the standards for L2BEAT are quite strict.

There are not many in the top 10 L2s that made it to Stage 1, and even those like Base, OP, and Unichain have been tagged; if they do not rectify within 53 days, they will drop back to Stage 0. Of course, they are all using OP Stack, so being tagged together is normal.

Among the top 5, only Arbitrum remains strong, considered the backbone of Stage 1 in L2...

The three-step 'auxiliary wheel' roadmap proposed by @VitalikButerin (Stage 0 → Stage 1 → Stage 2) has been transformed by L2BEAT into a concrete and measurable checklist (proof of usability, exit window, time lock, security committee design, etc.).

Specifically, what Stage an L2 is in depends on a core question: who can veto or change the state?

In Stage 0, the core team (or low-threshold multi-signatures) can override the proof system.

In Stage 1, only a supermajority security committee (≥ 75% signatures) can overturn it; all others (including the core team) must go through the proof system.

In Stage 2, the proof system itself is the final arbiter; the security committee can only intervene to fix provably on-chain vulnerabilities.

Especially in Stage 1, L2BEAT has quantified it specifically:

≥ 8 members in the security committee, with at least half being external members

≥ 7 days upgrade time lock ('exit window')

≥ 5 external validators

So I specifically looked at the current security committee situation of Arbitrum. In addition to foundation members, there are also L2BEAT co-founder Bartek Kiepuszewski, representatives from security or governance organizations like OpenZeppelin, Immunefi, Gauntlet, etc., totaling 12 members.

PS: Humorously, they directly invited the co-founder of L2BEAT to join, saving him from demoting every few days...

Normal upgrades proceed with a 9/12 multi-signature. Then, the Arb committee divides the members into 6+6, with half being re-elected each year.

After Arb Bold (Bounded Liquidity Delay) officially launched this February, the contract supports anyone staking to participate, submit/challenge assertions, which essentially completes the last task of Stage 1.

This is what has made Arbitrum one of the few truly Stage 1 L2s.

@arbitrum_cn @arbitrum