diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 2988cf2..946f35b 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -5,6 +5,9 @@ on:
 
 name: Continuous integration
 
+env:
+  RUSTFLAGS: '--deny warnings'
+
 jobs:
   ci-linux:
     runs-on: ubuntu-latest
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 9f0aa0d..d738ddc 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -5,6 +5,9 @@ on:
 
 name: Test Suite
 
+env:
+  RUSTFLAGS: '--deny warnings'
+
 jobs:
   ci-linux:
     runs-on: ubuntu-latest