Protocol v21 is live on the testnet with v1.18.1-rc. This release brings updates to congestion handling, faster commit sync, and changes to the Rust SDK. Testnet-only for now.

Protocol Updates

• Protocol v21 is now active on the testnet.
• #10313: Congestion limit overshoot is now enabled in the shared-object congestion tracker and the gas price feedback mechanism. Transactions using randomness also get a separate gas price feedback mechanism. All changes are testnet-specific.
• #9585: Fast commit syncer is enabled on Devnet using the consensus_fast_commit_sync flag. This improves the catch-up rate for fetching committed SubDAGs to ~20x-30x, compared to ~4x-6x without it.
• #10431: New AuthContext native functions added for getters.

Node Changes (Validators and Full Nodes)

• #10380: RestIndexStore is now included in database snapshots.
• #10420: Fixed bugs and re-enabled test_traffic_sketch_with_slow_blocks.
• #9585: Added enable_fast_commit_syncer as a local Starfish consensus parameter (default false). When enabled, nodes use FastCommitSyncer for faster recovery from large commit gaps, provided the protocol flag is active.

CLI Updates

• #10261: iota move build now supports the --client.env flag, allowing you to build a package with a specific network's address values.
• #10226: Fixed a bug where conflicting addresses weren't checked after compiling.

Rust SDK Changes

• #10431: Breaking change to MoveAuthenticator. It's now versioned and must be constructed as V1.

This release is a prerelease for testing purposes only. Full details and changelog: v1.18.1-rc Release Notes.

Sources: v1.18.1-rc, v1.18.0-rc