v1.7.0-rc4 - 2025-10-06

This is Charon's first Fulu-ready pre-release version. Feedback is welcome and appreciated, please use github issues or discord if you have trouble with this release.

Fulu Activation Schedule

Please consult the official Ethereum blog for the latest client versions to run ahead of the hardfork.

Apart from Fulu readiness, there are two major features in this release, both under feature flags:

Chain Split Safety Halt

If the feature flag chain_split_halt is enabled (--feature-set-enable=chain_split_halt), Charon nodes will verify that the target and source votes (FFG) of the attestation a consensus leader proposes to sign matches with their local beacon node's view of the network. If they differ, it means that the nodes are on different chains(forks). Charon will not progress consensus with a leader on a different fork, leading to a timeout and a new leader being chosen.

This means that if more than the fault tolerance of the cluster are on different chains(forks), the cluster will stop attesting until a threshold of nodes are on the same chain. This feature may protect your cluster in worst case slashing situations where a supermajority of nodes attest to the wrong chain. If your cluster does not have those faulty clients as a supermajority amongst its operators, and the opt-in feature is enabled, your cluster will halt rather than incorrectly attest and be doomed to slashing or activity leaking 100% of your principal.

Performance Improvement

Fetch only attestation data with committee index 0 (--feature-set-enable=fetch_only_commidx_0). In Electra the spec for fetching attestation data was changed, hardcoding the committee_index in the request to 0. However, most validator clients continued asking for the specific committee index, while the beacon nodes disregarded this field and returned the data. On Charon we are forced to make both requests in order to accommodate both behaviors in validator clients. Now, most VCs have updated their implementations, and we are releasing opt-in support for the performance improvement, if you confirm your VC supports the behaviour.

If you enable this feature flag you will reduce the amount of requests Charon sends to the beacon node for attestation data. For big clusters that might be as high as 63 requests less per slot. In big clusters with slower beacon nodes turning on this feature flag may improve attestation and efficiency rates.

Confirm in this linked issue for the latest info on whether validator client version is new enough to enable this feature. These release notes may not have the latest status on VC support.

Once all VCs request the correct committee index, this feature will be default-on in a future version of Charon.

Read the rest of the release notes for more:

Full Changelog: v1.6.1..v1.7.0-rc4

Feature

• Attestation source and target vote consensus - chain split halt #3876 #4011 (#3946)
• Fetcher fetch only attestation data with committee index 0 #3980 (#3989)
• Track SSE events block_gossip and block #3877 (#3938)
• Add publishing new cluster definition to Obol API with only --operator-enrs #3993
• Allow beacon node basic auth in URL #3926

Misc

• Turned on feature flag metric #3979 (#3994)
• Add self identification to logs #3919 (#3939)
• Allow pushing metrics to OTLP insecurely #3983
• Remove the pretty key from JSON logging #3924 (#4005)

Compatibility Matrix

This release of Charon is backwards compatible with Charon v1.0.*, v1.1.*, v1.2.0, v1.3.*, v1.4.*, v1.5.*, v1.6.* Though only v1.3.* and newer are Pectra-ready and none of the previous are Fulu-ready.

The below matrix details a combination of beacon node (consensus layer) + validator clients and their corresponding versions the DV Labs team have tested with this Charon release. More validator and consensus client will be added to this list as they are supported in our automated testing framework.

Legend

• ✅: All duties succeed in testing
• 🟡: All duties succeed in testing, except non-penalised aggregation duties
• 🟠: Duties may fail for this combination
• 🔴: One or more duties fails consistently

What's Changed

• app/version: bump to v1.7-dev (#3889)

• cmd: add hostname verification (#3901)

• cmd: renamed add-validators flags (#3902)

• dkg: add zipped flag (#3903)

• core: replace context.WithCancel with t.Context (#3905)

• *: bump go to v1.25 (#3910)

• app: fix some inconsistent function name in comment (#3912)

• *: added otlp headers (#3915)

• p2p: error on closing canceled stream (#3916)

• *: bump govulncheck to v1.1.4 (#3922)

• app: fallback buildinfo logic (#3930)

• *: codebase typos and spelling checked (#3936)

• core/fetcher: improve fee recipient checking (#3937)

• cmd: add missing space (#3957)

• p2p: separate peer and relay p2p metrics (#3971)

• dutydb: check only source and target for commidx 0 (#3974)

• *: otlp insecure flag (#3983)

• *: bump go-eth2-client to v0.27.0-obol.1 (#3985)

• *: bump golangci-lint to v2.5.0 (#3986)

• cmd: cleanup (#3990)

• *: allow --operator-enrs on publishing definition to API (#3993)

• core: fix some comment (#3995)

• app: bump version from dev to rc (#3997)

• *: v1.7.0-rc2 (#4003)

• *: v1.7.0-rc3 (#4008)

• *: v1.7.0-rc4 (#4013)