diff --git a/CHANGELOG.md b/CHANGELOG.md
index 13f34cd..f78c31d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [0.21.0] - 2024-12-18
+
 ### Changed
 
 - The build now fails early if known problematic Python and pip-related env vars have been set by the user or earlier buildpacks. ([#308](https://github.com/heroku/buildpacks-python/pull/308))
@@ -264,7 +266,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - Initial implementation. ([#3](https://github.com/heroku/buildpacks-python/pull/3))
 
-[unreleased]: https://github.com/heroku/buildpacks-python/compare/v0.20.1...HEAD
+[unreleased]: https://github.com/heroku/buildpacks-python/compare/v0.21.0...HEAD
+[0.21.0]: https://github.com/heroku/buildpacks-python/compare/v0.20.1...v0.21.0
 [0.20.1]: https://github.com/heroku/buildpacks-python/compare/v0.20.0...v0.20.1
 [0.20.0]: https://github.com/heroku/buildpacks-python/compare/v0.19.2...v0.20.0
 [0.19.2]: https://github.com/heroku/buildpacks-python/compare/v0.19.1...v0.19.2
diff --git a/buildpack.toml b/buildpack.toml
index 5c38003..a58731a 100644
--- a/buildpack.toml
+++ b/buildpack.toml
@@ -2,7 +2,7 @@ api = "0.10"
 
 [buildpack]
 id = "heroku/python"
-version = "0.20.1"
+version = "0.21.0"
 name = "Heroku Python"
 homepage = "https://github.com/heroku/buildpacks-python"
 description = "Heroku's buildpack for Python applications."