diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 7361f04..ff9c276 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -11,6 +11,10 @@ on:
         type: boolean
         default: false
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
 permissions:
   checks: write
   contents: read
diff --git a/CHANGELOG.md b/CHANGELOG.md
index d284e61..14bc997 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -22,6 +22,12 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   assistant policy, and project communication channels. Added
   `docs/branching.md` as the long-form companion covering the release
   workflow, version conventions, and merge-direction rationale.
+- CI workflow (`.github/workflows/ci.yml`) now declares a top-level
+  `concurrency` block keyed on `(workflow, ref)` with
+  `cancel-in-progress: true`. Force-pushes and rapid successive
+  pushes to the same ref now retire the in-flight run rather than
+  letting superseded and current-tip runs both consume runner minutes.
+  Tag-triggered release-build workflows are deliberately untouched.
 
 ### Fixed