(chore) prepare for release v2.2.0

Author: epwalsh

CHANGELOG.md

@@ -7,6 +7,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## Unreleased
 
+## [v2.2.0](https://github.com/allenai/OLMo-core/releases/tag/v2.2.0) - 2025-08-26
+
 ### Added
 
 - Added option to set LR scheduler based on tokens instead of steps (e.g. `--train_module.scheduler.units=tokens`).

src/olmo_core/version.py

@@ -1,5 +1,5 @@
 _MAJOR = "2"
-_MINOR = "1"
+_MINOR = "2"
 _PATCH = "0"
 _SUFFIX = ""