diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index b242a3f..d8fae0e 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -7,6 +7,9 @@ on:
     branches: [main]
   workflow_dispatch:
 
+permissions:
+  contents: read
+
 jobs:
   build-and-test:
     name: Build and run the test suite