[dfuse-bot]

World-chain v2.8.1 pins the optimism monorepo at op-reth/v2.8.1 (72207294) for op-reth, op-alloy, op-revm and alloy-op-evm. release/op-reth-2.x already merged exactly that tag (#28, tagged op-reth-v2.8.1-fh3.1), so this merges it into the world-chain line. Outside the reth pin and CHANGELOG.sf.md, the tree is identical to op-reth-v2.8.1-fh3.1.

Depends on streamingfast/reth#91. rust/Cargo.toml pins streamingfast/reth tag world-chain-v2.8.1-fh3.1, which does not exist until that PR is merged and its merge commit is tagged. The build (and sf-release.yml) fails until then. rust/Cargo.lock records the head of that PR (0d253a1b) for the tag; if the tag lands on another commit, refresh it with cargo update -p reth-firehose in rust/.

Release: once merged, tag the merge commit world-chain-v2.8.1-fh3.1.

Conflicts

The world-chain line was built from op-reth/v2.6.0 plus cherry-picks, the op-reth line from op-reth/v2.6.1. engine_validator.rs, proof_history.rs (deleted upstream, launch_node moved into node.rs), rust/Cargo.toml and rust/Cargo.lock conflicted. Both sides of the Rust files were identical at the previous tags, so each takes the op-reth side; the reth pins then move to the world-chain tag. CHANGELOG.sf.md keeps the world-chain history with a new section on top.

Firehose bug patterns

Same code as op-reth-v2.8.1-fh3.1; the review in #28 applies. I verified the op-revm range myself from da6d3252 (the previous world-chain pin), not op-reth/v2.6.1: handler.rs changed only in comments, and the only fork-gated change is the Lagoon BLS precompile input cap. World Chain maps Lagoon to Never.

CHANGELOG

## world-chain-v2.8.1-fh3.1

Moves the world-chain line to upstream `op-reth/v2.8.1` (`72207294`), the optimism rev world-chain
`v2.8.1` pins. Outside the reth pin and this changelog, the tree is the same as
`op-reth-v2.8.1-fh3.1`.

### Changed

* Merged `release/op-reth-2.x` at `op-reth-v2.8.1-fh3.1`, which merges upstream `op-reth/v2.8.1`
  and moves reth to ethereum-optimism/reth `op-v2.6.0-2` (reth v2.6.0), revm to 43 and alloy-evm
  to 0.39. The fee vault formulas, deposit handling and fork schedule the Firehose hooks depend on
  are unchanged.
* Reth now comes from `streamingfast/reth` `world-chain-v2.8.1-fh3.1`, which merges `op-v2.6.0-2`
  into `release/world-chain-2.x`.
* `alloy-evm` now comes from `streamingfast/evm` tag `v0.39.0-sf`, so block traces keep their
  `systemCalls`.
* The Firehose engine validator follows upstream's payload validator: a block whose transaction
  sender cannot be recovered is now rejected as an invalid block instead of failing with an
  internal error.
* Add `ACTIVATIONS.md`, which lists every OP hardfork with its status on OP Mainnet and Unichain
  and its effect on the Firehose block.

Tests

Built against the reth PR head through a local world-chain-v2.8.1-fh3.1 tag that was never pushed.

• cargo check --locked -p op-reth -p reth-optimism-firehose -p alloy-op-evm --tests: PASSED
• cargo test --locked -p reth-optimism-firehose -p alloy-op-evm -p reth-optimism-evm -p reth-optimism-node -p reth-optimism-payload-builder --no-fail-fast: PASSED (alloy-op-evm 114, reth-optimism-evm 58, reth-optimism-node 51 + 25 + 2 (1 ignored), reth-optimism-payload-builder 41 + 1, doc tests 3; reth-optimism-firehose has no unit tests)
• Battlefield: runs on the world-chain node, see the streamingfast/world-chain PR.