diff --git a/.gitattributes b/.gitattributes
index f76a15b..aaa3560 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -6,3 +6,10 @@
 /phpunit.xml.dist export-ignore
 /pint.json export-ignore
 /renovate.json export-ignore
+# Pollora harness (QA-06): development files stay out of the archive Composer downloads
+/.claude export-ignore
+/.harness.json export-ignore
+/AGENTS.md export-ignore
+/api-surface.json export-ignore
+/composer-dependency-analyser.php export-ignore
+/rector.php export-ignore
diff --git a/.github/workflows/harness.yml b/.github/workflows/harness.yml
index ad6e301..0164122 100644
--- a/.github/workflows/harness.yml
+++ b/.github/workflows/harness.yml
@@ -14,6 +14,6 @@ permissions: {}
 
 jobs:
   harness:
-    uses: Pollora/harness/.github/workflows/php-package.yml@v0.1.8
+    uses: Pollora/harness/.github/workflows/php-package.yml@v0.1.15
     permissions:
       contents: read
diff --git a/composer.json b/composer.json
index 45b9256..d9f9d18 100644
--- a/composer.json
+++ b/composer.json
@@ -33,7 +33,7 @@
         "mockery/mockery": "^1.6.12",
         "pestphp/pest": "^3.8.2",
         "phpstan/phpstan": "^2.1.16",
-        "pollora/harness": "^0.1.8",
+        "pollora/harness": "^0.1.15",
         "szepeviktor/phpstan-wordpress": "^2.0",
         "wp-cli/wp-cli": "^2.12"
     },