diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4610767..4636022 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,25 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [0.5.1] — 2026-05-31
+
+### Changed
+- Close out the **LLM-reduction roadmap (issue #33)**. All four levers ship and
+  are exercised by the test suite:
+  - **D — content-addressed completion cache** (`simplicio/_cache.py`,
+    `simplicio cache stats|clear`) with session hit/miss/put telemetry.
+  - **C — static verify-loop fixers** (`simplicio/pipeline_fixers.py`).
+  - **A — declarative plan recipes** (`simplicio/scratch/recipes.py`).
+  - **B — mechanical task executors** (`simplicio/scratch/codegen/*`) for
+    Python, TypeScript, Go, Rust and PHP, dispatched ahead of any task-level
+    LLM call.
+- The remaining empirical release-validation gate — a real 50-goal
+  codegen-disabled LLM baseline measuring B/codegen pass-rate and latency — is
+  tracked separately as a dedicated release-validation issue and does not block
+  this release. The repo-local closure audit
+  (`bench/results_issue_closure_audit.*`) continues to report that gate as open
+  by design, so partial evidence is never claimed as complete.
+
 ## [0.5.0] — 2026-05-31
 
 ### Added
diff --git a/pyproject.toml b/pyproject.toml
index eff7f06..e3b0797 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [project]
 name = "simplicio-cli"
-version = "0.5.0"
+version = "0.5.1"
 description = "Portable task-to-code pipeline that works with any LLM. Turn a one-line task into a verified code change — diff + test + verify loop. +55 pts on a 156-check benchmark, 21% faster, ~same tokens."
 readme = "README.md"
 license = { text = "MIT" }
diff --git a/simplicio/__init__.py b/simplicio/__init__.py
index 3d18726..dd9b22c 100644
--- a/simplicio/__init__.py
+++ b/simplicio/__init__.py
@@ -1 +1 @@
-__version__ = "0.5.0"
+__version__ = "0.5.1"
diff --git a/tests/python/test_package_metadata.py b/tests/python/test_package_metadata.py
index 329edec..b45d86a 100644
--- a/tests/python/test_package_metadata.py
+++ b/tests/python/test_package_metadata.py
@@ -7,7 +7,7 @@
 def test_package_version_matches_release_metadata() -> None:
     project = tomllib.loads(Path("pyproject.toml").read_text(encoding="utf-8"))["project"]
 
-    assert project["version"] == "0.5.0"
+    assert project["version"] == "0.5.1"
     assert __version__ == project["version"]