OffchainLabs/arbitrum-classic
Some data may be outdated — see provenance labels.
Powers fast, private, decentralized applications observed · 2026-09-23
Health v2 · maintenance only
84/100
- Activity 94
- Release rhythm 62
- Longevity 100
How is this computed?
round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10) — computed 2026-10-21. Adoption (stars, forks) is never an input.
- gap_med: 357
- age_days: 2633
- days_rel: 41
- days_push: 41
- n_releases_24m: 2
Adoption not part of the score
2001 stars · 1402 forks observed · 2026-09-23
What it is AI-extracted, prompt v1, taxonomy v1, 2026-08-30, confidence not recorded
Arbitrum Classic is the original Arbitrum Layer-2 optimistic rollup tech stack for Ethereum, implemented in Go, that powers fast and private decentralized applications. It is a legacy monorepo, as Arbitrum One was upgraded to the Nitro stack in August 2022.
Use cases
- run a legacy Arbitrum Classic node
- build dapps on the original Arbitrum rollup
- study the pre-Nitro Arbitrum validator and sequencer implementation
- maintain or migrate an app still on the classic Arbitrum stack
- research optimistic rollup execution in Go
When to choose
- you must operate or audit the legacy Arbitrum Classic chain
- you need to reference the original rollup implementation for research or migration
When to avoid
- you are building a new dapp or node on Arbitrum - use the Nitro codebase instead
- you want an actively developed Layer-2 stack
Facets
application · maturity maintenance
blockchain rpc developer-tools blockchain developer-tools microservices windows go cross-platform ethereum layer-2 optimistic-rollup arbitrum smart-contracts monorepo legacy deprecated-in-favor-of-nitro virtual-machine cryptocurrency linux macos
3 sources
- readme: https://github.com/OffchainLabs/arbitrum-classic · fetched 2026-09-23 · 11257a716aba
- homepage: https://offchainlabs.com/ · fetched 2026-08-29 · 8076c31383b2
- site_page: https://www.offchain.io/blog/research/debunking-common-misconceptions-about-timeboost · fetched 2026-08-29 · 8049a4a24c7e
Member repositories
| Repository | Role | Health v2 |
|---|---|---|
| OffchainLabs/arbitrum-classic | main | 84 |
For agents
markdown · JSON · MCP: product_card(name="OffchainLabs/arbitrum-classic")
Data as of 2026-10-19T08:05:51.212177+00:00 · Report a problem