Current mainnet EL — Fusaka
Status: Ready for the public MCP (not launched).
baselineForkIdin the probe — today’s mainnet execution-layer rules.
This page tracks whatever fork mainnet EL is on right now. Today that is Fusaka (EL alias osaka; role alias mainnet-el). After Glamsterdam activates on mainnet, this doc (and probe metadata) will switch to Glamsterdam as current / baselineForkId, and the next preview fork moves under Preview forks. Fusaka twins stay advertised (this page becomes history); they are not dropped on activation.
Fusaka today
ModExp repricing (7883), secp256r1 precompile (7951), and related Fusaka EL changes are active on mainnet. Use this fork to run those features (adoption at your own pace) as well as to compare against Pectra or Glamsterdam. Predecessor in lineage: Pectra (historical table). Preview successor: Glamsterdam.
Activated EIP numbers are in the probe (namedForks[].activatedEips, eipIntroductions). PeerDAS and blob-sidecar behaviour are not fully observable in this lab.
Runnable FYP twins on Fusaka
| EIP | Page |
|---|---|
| 7883 | ModExp gas |
| 7951 | secp256r1 |
Full index: EIP catalogue.
Compare
| Goal | Run twice |
|---|---|
| One Fusaka EIP vs before it existed | Pectra → Fusaka (from derived module comparison or eipIntroductions) |
| Upcoming fork vs mainnet today | Fusaka → Glamsterdam |
What you can ask your agent
- “Run this under current mainnet EL (Fusaka / mainnet-el).”
- “Verify this P-256 payload on Fusaka — does 0x100 return 0x01?”
- “Compare ModExp gas: Pectra then Fusaka.”
- “Same transfer on Fusaka vs Glamsterdam.”
Pass { "baseHardfork": "fusaka", "eips": [] } (or aliases osaka, mainnet-el). Fusaka is not the default lab fork — Glamsterdam is.
Provenance on a generic Fusaka run lists advertised modules 7883 and 7951 with eips: [].
Related
| Preview (Glamsterdam) | Default lab / upcoming |
| Historical forks | Paris → Pectra |
| EIP catalogue | Lineage + EIP twins |
| Fork timeline | External reference |
Changelog
- v0.62026-09-17Fusaka twins stay first-class after activation (adoption runs, not only compares).
- v0.52026-09-17Twin pages linked from this fork doc (sidebar no longer lists EIPs).
- v0.42026-09-17Canonical catalog id is fusaka; osaka is the EL alias; mainnet-el remains the role alias.
- v0.32026-09-16Doc framed as rotating mainnet section (Fusaka now; updates when mainnet fork changes).
- v0.22026-09-16Lineage and predecessor compare pattern.
- v0.12026-09-16Named fork capability — generic Fusaka runs.