Create CHANGELOG.md for easier communication of library changes, especially possible breaking changes.

CHANGELOG.md

@@ -0,0 +1,61 @@
+# Changelog
+
+## main / unreleased
+
+### What's Changed
+
+* [ENHANCEMENT] Create CHANGELOG.md for easier communication of library changes, especially possible breaking changes. https://github.com/prometheus/common/pull/833
+
+## v0.66.1 / 2025-09-05
+
+This release has no functional changes, it just drops the dependencies `github.com/grafana/regexp` and `go.uber.org/atomic` and replaces `gopkg.in/yaml.v2` with `go.yaml.in/yaml/v2` (a drop-in replacement).
+
+### What's Changed
+* Revert "Use github.com/grafana/regexp instead of regexp" by @aknuds1 in https://github.com/prometheus/common/pull/835
+* Move to supported version of yaml parser by @dims in https://github.com/prometheus/common/pull/834
+* Revert "Use go.uber.org/atomic instead of sync/atomic (#825)" by @aknuds1 in https://github.com/prometheus/common/pull/838
+
+**Full Changelog**: https://github.com/prometheus/common/compare/v1.20.99...v0.66.1
+
+## v0.66.0 / 2025-09-02
+
+### ⚠️ Breaking Changes ⚠️
+
+* A default-constructed TextParser will be invalid. It must have a valid `scheme` set, so users should use the NewTextParser function to create a valid TextParser. Otherwise parsing will panic with "Invalid name validation scheme requested: unset".
+
+### What's Changed
+* model: add constants for type and unit labels. by @bwplotka in https://github.com/prometheus/common/pull/801
+* model.ValidationScheme: Support encoding as YAML by @aknuds1 in https://github.com/prometheus/common/pull/799
+* fix(promslog): always print time.Duration values as go duration strings by @tjhop in https://github.com/prometheus/common/pull/798
+* Add `ValidationScheme` methods `IsValidMetricName` and `IsValidLabelName` by @aknuds1 in https://github.com/prometheus/common/pull/806
+* Fix delimited proto not escaped correctly by @thampiotr in https://github.com/prometheus/common/pull/809
+* Decoder: Remove use of global name validation and add validation by @ywwg in https://github.com/prometheus/common/pull/808
+* ValidationScheme implements pflag.Value and json.Marshaler/Unmarshaler interfaces by @juliusmh in https://github.com/prometheus/common/pull/807
+* expfmt: Add NewTextParser function by @aknuds1 in https://github.com/prometheus/common/pull/816
+
+* Enable the godot linter by @aknuds1 in https://github.com/prometheus/common/pull/821
+* Enable usestdlibvars linter by @aknuds1 in https://github.com/prometheus/common/pull/820
+* Enable unconvert linter by @aknuds1 in https://github.com/prometheus/common/pull/819
+* Enable the fatcontext linter by @aknuds1 in https://github.com/prometheus/common/pull/822
+* Enable gocritic linter by @aknuds1 in https://github.com/prometheus/common/pull/818
+* Use go.uber.org/atomic instead of sync/atomic by @aknuds1 in https://github.com/prometheus/common/pull/825
+* Enable revive rule unused-parameter by @aknuds1 in https://github.com/prometheus/common/pull/824
+* Enable revive rules by @aknuds1 in https://github.com/prometheus/common/pull/823
+* Synchronize common files from prometheus/prometheus by @prombot in https://github.com/prometheus/common/pull/802
+* Synchronize common files from prometheus/prometheus by @prombot in https://github.com/prometheus/common/pull/803
+* Sync .golangci.yml with prometheus/prometheus by @aknuds1 in https://github.com/prometheus/common/pull/817
+* ci: update upload-actions by @ywwg in https://github.com/prometheus/common/pull/814
+* docs: fix typo in expfmt.Negotiate by @wmcram in https://github.com/prometheus/common/pull/813
+* build(deps): bump golang.org/x/net from 0.40.0 to 0.41.0 by @dependabot[bot] in https://github.com/prometheus/common/pull/800
+* build(deps): bump golang.org/x/net from 0.41.0 to 0.42.0 by @dependabot[bot] in https://github.com/prometheus/common/pull/810
+* build(deps): bump github.com/stretchr/testify from 1.10.0 to 1.11.1 in /assets by @dependabot[bot] in https://github.com/prometheus/common/pull/826
+* build(deps): bump google.golang.org/protobuf from 1.36.6 to 1.36.8 by @dependabot[bot] in https://github.com/prometheus/common/pull/830
+* build(deps): bump golang.org/x/net from 0.42.0 to 0.43.0 by @dependabot[bot] in https://github.com/prometheus/common/pull/829
+* build(deps): bump github.com/stretchr/testify from 1.10.0 to 1.11.1 by @dependabot[bot] in https://github.com/prometheus/common/pull/827
+
+### New Contributors
+* @aknuds1 made their first contribution in https://github.com/prometheus/common/pull/799
+* @thampiotr made their first contribution in https://github.com/prometheus/common/pull/809
+* @wmcram made their first contribution in https://github.com/prometheus/common/pull/813
+* @juliusmh made their first contribution in https://github.com/prometheus/common/pull/807
+

RELEASE.md

@@ -11,7 +11,17 @@ With those steps done, you can proceed to cut a release.
 
 ## How to cut an individual release
 
-There is no automated process for cutting a release in `prometheus/common`. A manual release using GitHub's release feature via [this link](https://github.com/prometheus/prometheus/releases/new) is the best way to go. The tag name must be prefixed with a `v` e.g. `v0.53.0` and then you can use the "Generate release notes" button to generate the release note automagically ✨. No need to create a discussion or mark it a pre-release, please do mark it as the latest release if needed.
+There is no automated process for cutting a release in `prometheus/common`.
+The primary trigger for announcing a release is pushing a new version tag.
+
+NOTE: As soon as a new tag is created, many downstream projects will automatically create pull requests to update their dependency of prom/common.
+Make sure the release is ready to go, with an updated changelog including notices of any breaking changes, before pushing a new tag.
+
+Here are the basic steps:
+
+1. Update VERSION, applying the next logical version number, without any `v` prefix (e.g.  `0.53.0`).
+2. Update CHANGELOG.md, applying the new version number (this time including the `v` prefix, e.g. `v0.53.0`) and date to the changes listed under ``## main / unreleased`, and commit those changes to the main branch.
+2. Use GitHub's release feature via [this link](https://github.com/prometheus/prometheus/releases/new) to apply a new tag. The tag name must be prefixed with a `v` e.g. `v0.53.0` and then use the "Generate release notes" button to generate the release notes automagically ✨. No need to create a discussion or mark it a pre-release, please do make sure it is marked as the latest release.
 
 ## Versioning strategy
 

VERSION

@@ -0,0 +1 @@
+0.66.1