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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][Keep a Changelog] and this project adheres to [Semantic Versioning][Semantic Versioning].
+
+## [Unreleased]
+
+## [v0.2.0] - 2021-03-29
+### Changed
+- Renamed `RSAKeySizeBytes` to `rsaKeySizeBits`, which fixes the mismatch
+  between its name and its value, and also makes the variable private to the
+  userlib module. This means it cannot be referenced in student implementations.
+
+- Updated `Hash()` to return a []byte slice instead of a [64]byte array.
+
+### Fixed
+- Updated `HashKDF()` to return a more useful error message when the given key
+  is the wrong size.
+
+### Added
+- Added `DatastoreGetBandwidth()` and `DatastoreResetBandwidth()` functions to
+  help students write tests for the `AppendFile()` efficiency requirement.
+
+---
+
+## [Released]
+
+## [v0.1.0] - 2021-02-21
+CHANGELOG did not exist in this release.
+
+---
+
+<!-- Links -->
+[Keep a Changelog]: https://keepachangelog.com/
+[Semantic Versioning]: https://semver.org/
+
+<!-- Versions -->
+[Unreleased]: https://github.com/cs161-staff/project2-userlib/releases/v0.2.0...HEAD
+[Released]: https://github.com/cs161-staff/project2-userlib/releases
+[v0.2.0]: https://github.com/cs161-staff/project2-userlib/releases/v0.1.0...v0.2.0
+[v0.1.0]: https://github.com/cs161-staff/project2-userlib/releases/v0.1.0