diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index e4856ee08..7ebda1a2d 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -42,3 +42,12 @@ jobs:
       - name: Build
         run: |
           make output
+
+      - name: Check output
+        run: |
+          diff -u ${expected,output}/pwads/av/fast/af253503.zip/af253503.lmp
+          diff -u ${expected,output}/pwads/hr/movie/11hr7159.zip/11hr7159.lmp
+          diff -u ${expected,output}/pwads/mm/movie/30mm8356.zip/30mm8356.lmp
+          diff -u ${expected,output}/pwads/mm2/max/m2221807.zip/m2221807.lmp
+          diff -u ${expected,output}/pwads/requiem/movie/6039rq01.zip/6039rq01.lmp
+          echo "All outputs match expected; test passed."