diff --git a/CHANGELOG.md b/CHANGELOG.md
index 007eeb5..0370bd3 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,7 +6,23 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 
 
 ## [Unreleased]
-[Unreleased]: https://github.com/althonos/pyopal/compare/v0.5.0-a4...HEAD
+[Unreleased]: https://github.com/althonos/pyopal/compare/v0.5.0-a5...HEAD
+
+
+## [v0.5.0-a5] - 2024-01-19
+[v0.5.0-a5]: https://github.com/althonos/pyopal/compare/v0.5.0-a4...v0.5.0-a5
+
+### Added
+- `Alphabet.__eq__` implementation comparing letters.
+- `pool` argument to `pyopal.align` to support reusing a `ThreadPool`.
+
+### Changed
+- Update `Aligner.align` to use the `BaseDatabase` Cython API.
+
+### Fixed
+- Memory leak in `Aligner.align` caused by faulty allocation of pointer array.
+- `__repr__` implementations of `Alphabet` and `FullResult`.
+- `Alphabet.__getitem__` reading past the letters buffer.
 
 
 ## [v0.5.0-a4] - 2024-01-17
diff --git a/pyopal/_version.py b/pyopal/_version.py
index 2b4d986..a49449e 100644
--- a/pyopal/_version.py
+++ b/pyopal/_version.py
@@ -1 +1 @@
-__version__ = "0.5.0-a4"
+__version__ = "0.5.0-a5"