diff --git a/.github/workflows/build-linux.yml b/.github/workflows/build-linux.yml
index d141d267e..b678a71db 100644
--- a/.github/workflows/build-linux.yml
+++ b/.github/workflows/build-linux.yml
@@ -20,24 +20,24 @@ jobs:
         # Github Actions requires a single row to be added to the build matrix.
         # See https://help.github.com/en/articles/workflow-syntax-for-github-actions.
         name: [
-          # ubuntu-20.04-gcc-9,
-          # ubuntu-20.04-clang-9,
+          ubuntu-20.04-gcc-9,
+          ubuntu-20.04-clang-9,
           ubuntu-22.04-gcc-11,
           ubuntu-22.04-clang-14,
         ]
 
-        build_type: [Debug, Release]
+        build_type: [Release]
         build_unstable: [ON]
         include:
-          # - name: ubuntu-20.04-gcc-9
-          #   os: ubuntu-20.04
-          #   compiler: gcc
-          #   version: "9"
+          - name: ubuntu-20.04-gcc-9
+            os: ubuntu-20.04
+            compiler: gcc
+            version: "9"
 
-          # - name: ubuntu-20.04-clang-9
-          #   os: ubuntu-20.04
-          #   compiler: clang
-          #   version: "9"
+          - name: ubuntu-20.04-clang-9
+            os: ubuntu-20.04
+            compiler: clang
+            version: "9"
 
           - name: ubuntu-22.04-gcc-11
             os: ubuntu-22.04