diff --git a/README.md b/README.md
index 4f95c6d5..99c726ea 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,4 @@
-# dotSCAD 2.2
+# dotSCAD 2.2.1
 
 > **Reduce the burden of 3D modeling in mathematics.**
 
diff --git a/RELEASE.md b/RELEASE.md
index 0bb79e2e..5e392349 100644
--- a/RELEASE.md
+++ b/RELEASE.md
@@ -1,5 +1,13 @@
 > Version numbers are based on [Semantic Versioning](https://semver.org/).
 
+# v2.2.1
+Bugfixes:
+- `util/sort`: z not sorted.
+
+Improvements:
+- Faster when the `style` of `function_grapher` is `"LINES"` or `"HULL_LINES"`.
+- Dedup pixels of `pixel/px_polyline`, `pixel/px_circle`, `pixel/px_cylinder`, `pixel/px_sphere`, `pixel/px_polygon`.
+
 # v2.2
 - Bugfixes
   - `util/sort`: fix "search term not found" warning when `by` is `"idx"`.