diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index d536117..41cd858 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -11,6 +11,37 @@ default:
   tags:
     - build
 
+# ============================================================================
+# MANUAL TRIGGER: Run Full Test Matrix On Demand
+# ============================================================================
+# Click the play button in GitLab UI to run the full 42-language matrix
+# without needing to create a tag. Useful for load testing & pool churn.
+manual-matrix-run:
+  stage: test
+  script:
+    - echo "Generating full test matrix..."
+    - bash scripts/generate-matrix.sh --force-all
+    - echo "Matrix generated, triggering child pipeline..."
+  artifacts:
+    paths:
+      - test-matrix.yml
+    expire_in: 1 hour
+  rules:
+    - when: manual
+      allow_failure: true
+
+manual-matrix-trigger:
+  stage: test
+  needs:
+    - manual-matrix-run
+  trigger:
+    include:
+      - artifact: test-matrix.yml
+        job: manual-matrix-run
+    strategy: depend
+  rules:
+    - when: on_success
+
 # CI variables UNSANDBOX_PUBLIC_KEY, UNSANDBOX_SECRET_KEY, DEPLOY_KEY
 # are configured in GitLab Settings > CI/CD > Variables
 
diff --git a/scripts/generate-matrix.sh b/scripts/generate-matrix.sh
index ed829a3..4bace11 100755
--- a/scripts/generate-matrix.sh
+++ b/scripts/generate-matrix.sh
@@ -5,10 +5,15 @@
 set -e
 
 # CRITICAL: Tags ALWAYS run full test matrix, no matter what
+# Also support --force-all flag or FORCE_FULL_MATRIX env var for manual triggers
 if [ -n "$CI_COMMIT_TAG" ]; then
     echo "Tag detected ($CI_COMMIT_TAG) - forcing full test matrix"
     TEST_ALL="true"
     CHANGED_LANGS=""
+elif [ "$1" = "--force-all" ] || [ "$FORCE_FULL_MATRIX" = "true" ]; then
+    echo "Manual trigger - forcing full test matrix"
+    TEST_ALL="true"
+    CHANGED_LANGS=""
 else
     # Read changes from detect-changes output
     CHANGES=$(cat changes.json)