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CHANGELOG.md

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+# Changelog
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
+and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
+
+## [Unreleased]
+## [v1.0.0] - 2022-08-20
+The project has been around for nearly two years now, so I'm bumping the version to v1.0.0. 
+
+### Fixed
+* There was a bug reported where in some cases the `payee_node_key` wasn't calculated correctly.
+
+### Removed
+* The minimum supported PHP version is now PHP 7.4.0.
+
+### Added
+* The CI process now tests compatibility with PHP 8.1.0 as well.
+
+## [v0.2.0] - 2021-12-07
+### Added
+* Added support for PHP 8.0.0.
+
+## [v0.1.0] - 2021-01-26
+First version
+
+[Unreleased]: https://github.com/Jorijn/bitcoin-bolt11/compare/v1.0.0...HEAD
+[v1.0.0]: https://github.com/Jorijn/bitcoin-bolt11/compare/v0.2.0...v1.0.0
+[v0.2.0]: https://github.com/Jorijn/bitcoin-bolt11/compare/v0.1.0...v0.2.0