v1.6.0 - 2025-08-27

This is Charon's v1.6.0 release. Feedback is welcome and appreciated, please use github issues or discord if you have trouble with this release.

Read the rest of the release notes for more:

Full Changelog: v1.5.2..v1.6.0

Notable features

This release ships with opt-in support for the QUIC transport protocol. QUIC aims to improve performance in large, distant clusters. This may become a default feature in future versions once proven stable and well-incorporated across our stack.

To enable this feature, make the following additions:

• Add https://4.relay.obol.dev/ to your obol relay list, e.g. CHARON_P2P_RELAYS:-https://0.relay.obol.tech,https://2.relay.obol.dev,https://1.relay.obol.tech,https://4.relay.obol.dev/
• Add CHARON_FEATURESET_ENABLE=quic as an env variable
• Add CHARON_P2P_QUIC_ADDRESS=0.0.0.0:3610 as an env variable
• Allow UDP traffic on your port 3610. If you're using our docker-compose examples, your ports section should be like

  ports:
    - ${CHARON_PORT_P2P_TCP:-3610}:3610/tcp       # P2P TCP libp2p
    - ${CHARON_PORT_P2P_QUIC:-3610}:3610/udp       # P2P QUIC libp2p
  

This release also introduces new ways of modifying existing cluster which are still in alpha version and are not recommended for Mainnet usage:

• addvalidator command which adds N validators to an existing cluster. This requires a new deposit for newly added validators.
• node_merge.sh script which helps combining validator keys and configuration for single pair of nodes by merging two nodes' folders.
• cluster_merge.sh script which helps expand an existing cluster with new validators by merging two existing clusters, given the same operators set and cluster configuration.

Feature

• Launchpad link per network (#3886)
• charon --split-existing-keys support multiple formats (#3872)
• cluster-lock merge script (#3847)
• Support deleting partial exits (#3838)
• Add add-validators command (#3857)
• Replace go-eth2-client with in-house solution (#3862)
• Put QUIC behind a feature flag (#3814)
• Add zipped flag to DKG (#3903)
• Add hostname verification (#3901)

Bug

• Invalid UUIDs are generated (#3887)
• Memory leak under attestation_inclusion feature flag (#3867)
• Increased duty timeout margin (#3800)
• Set content type in alpha test (#3808)
• Fixed vapi monitoring code (#3812)
• Fix attestation committee index (#3820)
• Remove fulu from fork schedule (#3822)
• Add missing encoding types (#3853)
• Fix flaky test (#3888)

Refactor

• Added sse_head_delay buckets (#3795)
• Changed reorg gauge to historgram (#3796)
• Changed sse-head-delay buckets (#3816)
• Replace HasPrefix+TrimPrefix with CutPrefix (#3824)
• Use maps.Copy for cleaner map handling (#3856)
• Improve fallback beacon node logic and metric (#3870)
• Batch duplicate logs (#3835)
• combine default input should align with create cluster default output. (#3815)

Compatibility Matrix

This release of Charon is backwards compatible with Charon v1.0.*, v1.1.*, v1.2.0, v1.3.*, v1.4.*, v1.5.* Though only v1.3.* and newer are Pectra-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: bump to v1.6-dev (#3792)

• app: added sse_head_delay buckets (#3795)

• *: changed reorg gauge to historgram (#3796)

• core: increased duty timeout margin (#3800)

• cmd: testinfra to verify io perm (#3806)

• cmd: test publish using temp enr key (#3807)

• cmd: set content type in alpha test (#3808)

• app: fixed vapi monitoring code (#3812)

• app: changed sse-head-delay buckets (#3816)

• *: fix attestation committee index (#3820)

• utils: remove fulu from fork schedule (#3822)

• testutil: replace HasPrefix+TrimPrefix with CutPrefix (#3824)

• core: fix some function names in comment (#3833)

• *: bump linter to v2.2.1 (#3837)

• core: make function comment match function name (#3845)

• *: removed addvalidators command (#3850)

• core/validatorapi: add missing encoding types (#3853)

• *: bump linter v2.2.2 (#3855)

• *: use maps.Copy for cleaner map handling (#3856)

• docs: update dv-launchpad URL to launchpad.obol.org (#3858)

• workflows: remove unused Discord webhooks (#3864)

• core/tracker: fix tracker inclusion after PR clash (#3873)

• *: bump linter v2.3.1 (#3883)

• cmd: launchpad link per network (#3886)

• app/eth1wrap: fix flaky test (#3888)

• app/version: bump to v1.6-rc (#3890)

• cmd: add hostname verification (#3901)

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

• dkg: add zipped flag (#3903)

• *: v1.6.0-rc2 cherry-picking (#3906)

• *: v1.6.0-rc3 cherry-picking (#3918)

• *: v1.6.0-rc4 cherry-picking (#3928)

• *: v1.6.0-rc5 cherry-picking (#3931)

• app/version: bump to v1.6 (#3932)