This version is backwards compatible to [v1.14.0](https://github.com/ava-labs/avalanchego/releases/tag/v1.14.0). It is optional, but encouraged.

The plugin version is updated to `45`; all plugins must update to be compatible.

## Breaking Changes

- Removed `graft/subnet-evm/compatibility.json` in favor of using a single source of truth in `version/compatibility.json`. External tools that relied on this file should now use `version/compatibility.json` from the main AvalancheGo repository.

## Config

- Added:
  - `--simplex-max-network-delay`
  - `--simplex-max-rebroadcast-wait`
  - `--benchlist-halflife`
  - `--benchlist-unbench-probability`
  - `--benchlist-bench-probability`
  - `snowParameters` in subnet configs
  - `simplexParameters` in subnet configs
- Deprecated:
  - `consensusParameters` in subnet configs
- Removed:
  - `--benchlist-fail-threshold`
  - `--benchlist-min-failing-duration`
  - `pull-gossip-poll-size` from the X-chain and P-chain configs
  - `proposerMinBlockDelay` from subnet configs

## API

- Added `avalanche_snowman_consensus_latencies` histogram for each chain

## Fixes

- Fixed potential FATAL during startup due to an incorrect initialization of remaining disk space
- Fixed crash in `TraceCall` with `BlockOverrides`
- Fixed snapshot generation shutdown race
- Downgraded flaky `ERROR` log to `WARN` if recently bootstrapped
- Updated minimum Go version from 1.24 to `v1.25.8`

## Consensus

- Redesigned benchlisting with predicated failure rates
- Added health checks to ensure average block acceptance times are reasonable
- Introduced Simplex consensus engine and parameters (experimental)

## Firewood

- Enabled Firewood deferred persistence for non-pruning nodes
- Fixed Firewood metrics registration
- Unsupported APIs now return an error when Firewood is enabled
- Updated Firewood to v0.3.1 (from v0.0.18)

## What's Changed

- Prep Firewood x/sync for EVM by @alarso16 in https://github.com/ava-labs/avalanchego/pull/4794
- [ci] Migrate reexec tasks to a script to simplify maintenance by @maru-ava in https://github.com/ava-labs/avalanchego/pull/4761
- refactor: Share EVM Utils by @alarso16 in https://github.com/ava-labs/avalanchego/pull/4739
- ci: ensure generated files up to date in CI by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4782
- fix: Always register Firewood metrics when enabled by @alarso16 in https://github.com/ava-labs/avalanchego/pull/4793
- refactor: directly embed files in `graft` by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4795
- chore: remove end year from license headers by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4812
- test(reexecute): add firewood chaos test [2/2] by @RodrigoVillar in https://github.com/ava-labs/avalanchego/pull/4695
- refactor: Firewood Config helper by @alarso16 in https://github.com/ava-labs/avalanchego/pull/4811
- chore(chaos): remove chaos test from PR CI by @RodrigoVillar in https://github.com/ava-labs/avalanchego/pull/4817
- feat(reexecution): collect leveldb and meterdb metrics by @DracoLi in https://github.com/ava-labs/avalanchego/pull/4804
- refactor: warp e2e tests no longer in single function by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4798
- build: bundle subnet-evm releasing into releasing workflow by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4675
- fix: warp e2e flake by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4818
- Provide a useful default for disk percentage by @StephenButtolph in https://github.com/ava-labs/avalanchego/pull/4822
- refactor: Use `state.Database` to generate tries in sync test helpers by @alarso16 in https://github.com/ava-labs/avalanchego/pull/4814
- chore: cleanup `graft/evm` post subnet-evm merge by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4752
- test: fix `TestUptimeSignatures` flake by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4826
- test: add Coreth + Firewood archive UT by @RodrigoVillar in https://github.com/ava-labs/avalanchego/pull/4820
- Introduce gossip system helper by @StephenButtolph in https://github.com/ava-labs/avalanchego/pull/4819
- test: fix `TestAtomicSyncerVM/StateSyncFromScratchTest` flake by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4825
- [direnv] Enable global envrc customization by @maru-ava in https://github.com/ava-labs/avalanchego/pull/4821
- fix(c-chain-reexecution): support genesis execution by @Elvis339 in https://github.com/ava-labs/avalanchego/pull/4841
- Remove `ProposerMinBlockDelay` from subnet configs by @StephenButtolph in https://github.com/ava-labs/avalanchego/pull/4824
- fix(eth/tracers): fix crash in TraceCall with BlockOverrides by @dmkulazhenko in https://github.com/ava-labs/avalanchego/pull/4657
- Fix flake in `TestWaitForEvent/WaitForEvent_build_block_after_re-org` by @yacovm in https://github.com/ava-labs/avalanchego/pull/4789
- fix: apply TraceCall fix in both coreth and subnet-evm by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4846
- Fix race in tests on VM Shutdown by @alarso16 in https://github.com/ava-labs/avalanchego/pull/4852
- refactor: use vms/evm customrawdb in subnet-evm by @alarso16 in https://github.com/ava-labs/avalanchego/pull/4851
- test: enable c-chain <-> subnet e2e warp tests by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4799
- refactor: align `PointerTo` functions by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4741
- chore: cleanup customtypes by @alarso16 in https://github.com/ava-labs/avalanchego/pull/4844
- chore: retype `DelayExcess`  by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4833
- refactor: share triedb by @alarso16 in https://github.com/ava-labs/avalanchego/pull/4843
- refactor: Share core/state by @alarso16 in https://github.com/ava-labs/avalanchego/pull/4863
- test(reexecution): add additional Firewood archival tests by @RodrigoVillar in https://github.com/ava-labs/avalanchego/pull/4853
- build: bump to go 1.24.12 by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4867
- test: Fix `TestResyncNewRootAfterDeletes` flake by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4850
- refactor: granite cleanup - remove `GetWarpValidatorSet` by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4858
- [nix] Update golang flake input for nix 2.25+ by @maru-ava in https://github.com/ava-labs/avalanchego/pull/4875
- feat(vm_reexecute): add pprof profiling support by @Elvis339 in https://github.com/ava-labs/avalanchego/pull/4790
- refactor: granite cleanup - remove pre-granite test-cases by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4860
- refactor(sync): reorganize state sync packages by @powerslider in https://github.com/ava-labs/avalanchego/pull/4857
- Simplex nits & bug fixes by @samliok in https://github.com/ava-labs/avalanchego/pull/4885
- feat: add Sync to database.HeightIndex by @DracoLi in https://github.com/ava-labs/avalanchego/pull/4839
- refactor: granite cleanup - remove `remoteDelayExcess`  by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4859
- refactor: share log package by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4886
- perf: Share proposal between hash and commit by @alarso16 in https://github.com/ava-labs/avalanchego/pull/4697
- refactor: remove strict mode in ABI by @alarso16 in https://github.com/ava-labs/avalanchego/pull/4884
- Firewood v0.1.0 by @alarso16 in https://github.com/ava-labs/avalanchego/pull/4893
- Return range proofs for change proof requests during Firewood sync by @alarso16 in https://github.com/ava-labs/avalanchego/pull/4834
- feat: Add interface between x/sync and EVM syncers by @alarso16 in https://github.com/ava-labs/avalanchego/pull/4832
- Add test coverage for acp118 replay protection by @joshua-kim in https://github.com/ava-labs/avalanchego/pull/4889
- refactor: remove UnpackInput by @alarso16 in https://github.com/ava-labs/avalanchego/pull/4901
- refactor: share EVM rpc package by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4786
- refactor: share version across codebase by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4891
- Update vms/README.md by @meaghanfitzgerald in https://github.com/ava-labs/avalanchego/pull/4904
- [ci] Support running re-execution benchmark with arbitrary version of Firewood by @Elvis339 in https://github.com/ava-labs/avalanchego/pull/4650
- test: address geth flakes by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4902
- refactor: Use libevm accounts/abi by @alarso16 in https://github.com/ava-labs/avalanchego/pull/4865
- [ci] Simplify run-monitored-tmpnet-cmd to use custom actions by @maru-ava in https://github.com/ava-labs/avalanchego/pull/4897
- [tools] Allow ./tools path to be used for local tools by @maru-ava in https://github.com/ava-labs/avalanchego/pull/4896
- test: Ensure code hashes are retrieved in Firewood by @alarso16 in https://github.com/ava-labs/avalanchego/pull/4915
- Add proposervm block delay logs by @yacovm in https://github.com/ava-labs/avalanchego/pull/4917
- Update consensus logs by @StephenButtolph in https://github.com/ava-labs/avalanchego/pull/4920
- Add go workspace by @maru-ava in https://github.com/ava-labs/avalanchego/pull/4899
- Create histogram for consensus latencies by @yacovm in https://github.com/ava-labs/avalanchego/pull/4924
- refactor(graft/evm): extract unified `message` package from `coreth` and `subnet-evm` by @powerslider in https://github.com/ava-labs/avalanchego/pull/4882
- Move x/sync and firewood to database by @alarso16 in https://github.com/ava-labs/avalanchego/pull/4929
- Remove legacy golang build tags by @maru-ava in https://github.com/ava-labs/avalanchego/pull/4933
- Fix go-mod-tidy and ensure it is checked in CI by @maru-ava in https://github.com/ava-labs/avalanchego/pull/4934
- chore: fix network logs typo  by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4941
- docs: fix getutxos incorrect type  by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4943
- Fail HealthCheck if Average Block Acceptance Times are too High by @samliok in https://github.com/ava-labs/avalanchego/pull/4911
- refactor: share constants between avalanchego and subnet-evm by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4914
- Simplify go version maintenance by @maru-ava in https://github.com/ava-labs/avalanchego/pull/4950
- Add latest checkpoints to reexecute benchmark for hashdb by @aaronbuchwald in https://github.com/ava-labs/avalanchego/pull/4953
- [ci] Configure dir exclusion from linting via .golangci.yml by @maru-ava in https://github.com/ava-labs/avalanchego/pull/4940
- chore: only tag subnet-evm on stable releases by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4951
- chore: sync handler param name by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4937
- chore: rename `atomicTrieDB`  by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4936
- Use clock time instead of time.Until in proposerVM by @yacovm in https://github.com/ava-labs/avalanchego/pull/4958
- Fix coreth and subnet-evm flaky tests by @rrazvan1 in https://github.com/ava-labs/avalanchego/pull/4947
- Remove Start/Wait mechanic in x/sync by @alarso16 in https://github.com/ava-labs/avalanchego/pull/4926
- [ci] Free up space to get the subnet evm antithesis test job passing by @maru-ava in https://github.com/ava-labs/avalanchego/pull/4967
- [ci] Add RPM release workflow by @maru-ava in https://github.com/ava-labs/avalanchego/pull/4959
- [ci] Ensure rpm packaging compatibility with legacy subnet-evm by @maru-ava in https://github.com/ava-labs/avalanchego/pull/4970
- Update to go `v1.25.7` by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4961
- [ci] Skip RPM upload for PRs by @maru-ava in https://github.com/ava-labs/avalanchego/pull/4974
- ci: change PR fuzz tests timing and bump fuzz test timeout  by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4978
- ci: just fuzz a single test by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4989
- docs: rewrite releasing readme by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4749
- refactor(sync): extract coreth/sync to evm/sync and adapt coreth and subnet-evm by @powerslider in https://github.com/ava-labs/avalanchego/pull/4921
- Switch to using solc provided by nix by @maru-ava in https://github.com/ava-labs/avalanchego/pull/4787
- Enable multi-module release and consumption strategy by @maru-ava in https://github.com/ava-labs/avalanchego/pull/4905
- feat: Remove FreeListCache from Firewood config by @alarso16 in https://github.com/ava-labs/avalanchego/pull/4963
- [nix] Switch to direct import of golang to fix relative path bug by @maru-ava in https://github.com/ava-labs/avalanchego/pull/5000
- [tmpnet] Annotate pods for collection to grafana cloud by @maru-ava in https://github.com/ava-labs/avalanchego/pull/4981
- test: skip StateSyncToggleEnabledToDisabledTest flake by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/5002
- fix: skip flaky firewood test due to go bump by @RodrigoVillar in https://github.com/ava-labs/avalanchego/pull/5001
- chore: upgrade lint to 2.9.0 by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4962
- refactor: in-line network stats package by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4887
- fix: skip TestConflictingImportTxsAcrossBlocks if using Firewood by @RodrigoVillar in https://github.com/ava-labs/avalanchego/pull/5018
- Remove Validator State Interface by @samliok in https://github.com/ava-labs/avalanchego/pull/4983
- docs: add missing APIs to Coreth docs by @ceyonur in https://github.com/ava-labs/avalanchego/pull/5020
- Migrate subnet-evm antithesis builder to the root by @PlatCore in https://github.com/ava-labs/avalanchego/pull/4836
- rename coreth api.md to service.md by @ceyonur in https://github.com/ava-labs/avalanchego/pull/5024
- fix: remove build arguement by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/5029
- Update Firewood to v0.2.0 by @alarso16 in https://github.com/ava-labs/avalanchego/pull/5030
- Move validator metadata DB writes into validatorState by @DracoLi in https://github.com/ava-labs/avalanchego/pull/5008
- Restrict benchmark auto-push to scheduled runs only by @aaronbuchwald in https://github.com/ava-labs/avalanchego/pull/5032
- Improve readability of ValidatorWeightDiff logic by @StephenButtolph in https://github.com/ava-labs/avalanchego/pull/5042
- test: blockchain test cleanup by @alarso16 in https://github.com/ava-labs/avalanchego/pull/5035
- Replace DelegateeReward API with generalized API by @rrazvan1 in https://github.com/ava-labs/avalanchego/pull/5017
- fix: only ignore specific firewood directory by @RodrigoVillar in https://github.com/ava-labs/avalanchego/pull/5047
- build: add ACP-224 interface and build ABI +  bindings  by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4871
- Add simplex consensus parameters by @samliok in https://github.com/ava-labs/avalanchego/pull/4870
- Introduce Simplex Engine Struct by @samliok in https://github.com/ava-labs/avalanchego/pull/4903
- Nits From Engine PR by @samliok in https://github.com/ava-labs/avalanchego/pull/5053
- Benchlist response handling by @aaronbuchwald in https://github.com/ava-labs/avalanchego/pull/4964
- update libevm to v1.13.14-0.4.0.rc.2 by @ceyonur in https://github.com/ava-labs/avalanchego/pull/5058
- Update to go 1.25.8 by @alarso16 in https://github.com/ava-labs/avalanchego/pull/5055
- PlatformVM: Support arbitrary validator addition and deletions by @yacovm in https://github.com/ava-labs/avalanchego/pull/5003
- Remove State Interface by @samliok in https://github.com/ava-labs/avalanchego/pull/5025
- Add back EWMA benching logic by @aaronbuchwald in https://github.com/ava-labs/avalanchego/pull/4982
- Remove Manager Interface From platformvm/validators by @samliok in https://github.com/ava-labs/avalanchego/pull/5056
- benchlist: greedy eviction to bench worst offenders at capacity by @aaronbuchwald in https://github.com/ava-labs/avalanchego/pull/5028
- [antithesis] Halve duration of triggered jobs by @maru-ava in https://github.com/ava-labs/avalanchego/pull/5054
- Remove State Interface from platformvm/validators by @samliok in https://github.com/ava-labs/avalanchego/pull/5057
- Early return unsupported APIs in Firewood by @alarso16 in https://github.com/ava-labs/avalanchego/pull/5075
- Add Firewood as a state syncer by @alarso16 in https://github.com/ava-labs/avalanchego/pull/4913
- Unskip tests skipped due to firewood stack corruption issue by @demosdemon in https://github.com/ava-labs/avalanchego/pull/5072
- [bazel] Enable initial build and test by @maru-ava in https://github.com/ava-labs/avalanchego/pull/4544
- Selectively log warning or error depending on how much time elapsed since bootstrapping finished by @yacovm in https://github.com/ava-labs/avalanchego/pull/5082
- feat(benchmark-cchain): add 40m-41m test cases for hashdb and firewood by @Elvis339 in https://github.com/ava-labs/avalanchego/pull/5088
- Upgrade to Firewood v0.3.0 by @alarso16 in https://github.com/ava-labs/avalanchego/pull/5085
- [bazel] Fix metadata generation on macos by @maru-ava in https://github.com/ava-labs/avalanchego/pull/5090
- Snapshot generation shutdown race by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/4816
- feat: enable Firewood deferred persistence by @RodrigoVillar in https://github.com/ava-labs/avalanchego/pull/5022
- chore: increase Firewood commit interval by @RodrigoVillar in https://github.com/ava-labs/avalanchego/pull/5091
- build(deps): bump google.golang.org/grpc from 1.75.0 to 1.79.3 by @dependabot[bot] in https://github.com/ava-labs/avalanchego/pull/5100
- build(deps): bump go.opentelemetry.io/otel/sdk from 1.37.0 to 1.40.0 by @dependabot[bot] in https://github.com/ava-labs/avalanchego/pull/5036
- [ci]  Disable monitoring checks for grafana cloud migration by @maru-ava in https://github.com/ava-labs/avalanchego/pull/4298
- [ci] Migrate monitoring to grafana cloud by @maru-ava in https://github.com/ava-labs/avalanchego/pull/4299
- Update Firewood to v0.3.1 by @alarso16 in https://github.com/ava-labs/avalanchego/pull/5107
- Remove Diff Interface From State by @samliok in https://github.com/ava-labs/avalanchego/pull/5099
- refactor: introduce base trie by @RodrigoVillar in https://github.com/ava-labs/avalanchego/pull/5113
- use UTXOs() in state assertion in executor tests by @samliok in https://github.com/ava-labs/avalanchego/pull/5132
- INFRA-6664: Update fuji boostrappers.json list with new IPs after migration to sa-east-1 from me-south-1 by @stylianosrigas in https://github.com/ava-labs/avalanchego/pull/5125
- Update canoto to v0.18.0 by @StephenButtolph in https://github.com/ava-labs/avalanchego/pull/5137
- chore: release v1.14.2 by @JonathanOppenheimer in https://github.com/ava-labs/avalanchego/pull/5135

## New Contributors

- @dmkulazhenko made their first contribution in https://github.com/ava-labs/avalanchego/pull/4657
- @PlatCore made their first contribution in https://github.com/ava-labs/avalanchego/pull/4836
- @demosdemon made their first contribution in https://github.com/ava-labs/avalanchego/pull/5072
- @stylianosrigas made their first contribution in https://github.com/ava-labs/avalanchego/pull/5125

**Full Changelog**: https://github.com/ava-labs/avalanchego/compare/v1.14.1...v1.14.2