Release Notes - v0.74.0

v0.74.0

Title: Improve ledger compatibility, synchronization, and observability

Date: 2026-09-30

Version: v0.74.0

Release: v0.74.0

This release strengthens ledger compatibility across Dijkstra and Byron eras, improves synchronization and blockfetch behavior, expands operational visibility, and refreshes supporting dependencies.

Recommended Network Compatibility ⚠️

Network	Compatible
mainnet	⛔
preprod-testnet	✅
preview-testnet	✅
musashi	✅

Ledger, compatibility, and synchronization improvements

• Improved Dijkstra nested transaction processing at the sub-transaction body level across live application, rollback and replay, backfill, Mithril gap recovery, and conformance paths. Direct deposits and ordered governance now follow the same state transitions in each path.

• Reduced false peer exclusions by accepting headers that the node already applied and postponing verification after the node prunes the required pool snapshot.

• Normalized Vector Testnet Conway genesis JSON by accepting genDelegs and legacy committee.quorum while still rejecting duplicate or unknown fields. The decoder now reads one JSON value without waiting for end of file.

• Expanded Byron compatibility with EBB and PBFT limits, a configurable PBftSignatureThreshold, legacy Musashi Dijkstra storage decoding, strict peer decoding, and normalized Leios transactions.

• Applied the minimum header batch when early synchronization switches peers, allowing the new peer to continue with the smallest required batch.

• Updated OpenTelemetry stdout tracing from v1.45.0 to v1.46.0.

• Refreshed Google Cloud Storage from v1.67.0 to v1.68.0.

• Detected missing pools by comparing total active stake with Koios and preserved per-pool mismatches when Koios cannot provide epoch information.

• Optimized blockfetch ranges around estimated wire size with an 8 MiB cap, ExpectedBytes, and an in-flight budget of three times the range size.

• Upgraded google.golang.org/api to v0.299.0 together with its related modules.

• Advanced gRPC to v1.86.0-dev and refreshed its Envoy dependency.

• Added opt-in from-genesis Prometheus metrics, new liveness alerts, a reference label, and metrics for incomplete checks.

• Corrected Babbage and Conway reward calculations to use d=0 while retaining the performance-era value for block counting.

• Introduced the Byron update-system state transition and adopted protocol parameters, with stricter checks for boundaries, sizes, fees, and TxAux values.

• Modernized gouroboros to v0.208.3 and changed transaction-submission pipeline error handling. Dingo no longer emits the dingo_ledger_block_pipeline_apply_pending_limit_errors_total metric.

• Aligned Byron EBB placement and ordering with configured epoch lengths and added validation for update votes and adoption boundaries.

• Updated aws/smithy-go to v1.28.2.

• Removed old example applications and moved Preview Koios parity monitoring into an opt-in DevNet Compose profile.

• Automated a non-blocking Homebrew tap update job and standardized release commit hashes.

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Docs authored by Doc Holiday