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Releasing.md

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+# Releasing AsyncMonitor
+
+There's no schedule here. Ship bug fixes whenever, features when they're ready, and breaking changes as rarely as you can stand.
+
+AsyncMonitor is a Swift package and a release is just a git tag. SwiftPM resolves versions directly from tags.
+
+## Before You Cut a Release
+
+Run the tests and make sure they pass.
+
+```shell
+swift test
+```
+
+Check that you're on `main` with a clean working tree, and that nothing looks weird in the recent history.
+
+```shell
+git status
+git log -5 --oneline
+```
+
+## Update the Changelog
+
+Find the `[Unreleased]` section in [Changelog.md](./Changelog.md), rename it to the new version, stamp it with today's date, and add the diff link at the bottom of the section.
+
+```markdown
+## [0.4.0] - 2026-05-17
+
+### Removed
+- Description of removals
+
+### Changed
+- Description of changes
+
+### Fixed
+- Description of fixes
+
+### Added
+- Description of additions
+
+[0.4.0]: https://github.com/samsonjs/AsyncMonitor/compare/0.3.1...0.4.0
+```
+
+Drop the "Your change here." placeholder if it's still there, and drop any of the Removed/Changed/Fixed/Added sections that don't actually have anything in them.
+
+Commit and push.
+
+```shell
+git add Changelog.md
+git commit -m "Prepare for release 0.4.0"
+git push github main
+```
+
+## Tag and Release on GitHub
+
+Tag it, push the tag, and cut the release. GitHub will generate notes from merged PRs and commits since the last tag:
+
+```shell
+git tag 0.4.0
+git push github 0.4.0
+gh release create 0.4.0 --verify-tag --generate-notes
+```
+
+If you'd rather use your changelog entry as the release body, this pulls just that section out:
+
+```shell
+gh release create 0.4.0 --verify-tag --notes "$(awk '/^## \[0\.4\.0\]/,/^## \[/' Changelog.md | sed '$d')"
+```
+
+## Start the Next Version
+
+Drop a fresh `[Unreleased]` section at the top of [Changelog.md](./Changelog.md) so there's somewhere to write down the next round of changes.
+
+```markdown
+## [Unreleased]
+
+- Your change here.
+
+[Unreleased]: https://github.com/samsonjs/AsyncMonitor/compare/0.4.0...HEAD
+```
+
+Commit and push and you're done.
+
+```shell
+git add Changelog.md
+git commit -m "Start next changelog entry"
+git push github main
+```