diff --git a/.release-please-manifest.json b/.release-please-manifest.json
index 0967ef4..11fea0f 100644
--- a/.release-please-manifest.json
+++ b/.release-please-manifest.json
@@ -1 +1 @@
-{}
+{".":"1.0.0"}
diff --git a/CHANGELOG.md b/CHANGELOG.md
new file mode 100644
index 0000000..afb58ed
--- /dev/null
+++ b/CHANGELOG.md
@@ -0,0 +1,8 @@
+# Changelog
+
+## 1.0.0 (2026-08-07)
+
+
+### Features
+
+* initial open source release ([dfd9dc6](https://github.com/spotify/confidence-metrics-sync/commit/dfd9dc6b0575a3146e3f194109d6693e9b97fd11))
diff --git a/action.yml b/action.yml
index bfaf147..c1a7401 100644
--- a/action.yml
+++ b/action.yml
@@ -35,7 +35,7 @@ runs:
       shell: bash
       env:
         CONFIDENCE_METRICS_RELEASE_ROOT: https://github.com/spotify/confidence-metrics-sync/releases/download
-        CONFIDENCE_METRICS_VERSION: 0.0.0 # x-release-please-version
+        CONFIDENCE_METRICS_VERSION: 1.0.0 # x-release-please-version
       run: "$GITHUB_ACTION_PATH/scripts/install.sh"
 
     - name: Run Confidence metrics