diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index b80888d..b4d522c 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -13,17 +13,29 @@ jobs:
     strategy:
       matrix:
         include:
+          - os: ubuntu-latest
+            compiler: g++-7
+            install: g++-7
           - os: ubuntu-latest
             compiler: g++-9
           - os: ubuntu-latest
             compiler: g++-10
             extra_build_flags: -DENABLE_COVERAGE:BOOL=ON # coverage build
+          - os: ubuntu-latest
+            compiler: g++-11
+            install: g++-11
+          - os: ubuntu-latest
+            compiler: clang++-7
+            install: clang-7
           - os: ubuntu-latest
             compiler: clang++-10
           - os: ubuntu-latest
             compiler: clang++-11
           - os: ubuntu-latest
             compiler: clang++-12
+          - os: ubuntu-22.04 # beta, not latest ATTOW
+            compiler: clang++-13
+            install: clang-13
           - os: macos-latest
             compiler: g++-9
           - os: macos-latest
@@ -41,6 +53,12 @@ jobs:
       with:
         fetch-depth: 2 # Codecov requests >1
 
+    - name: Install compiler
+      if: ${{matrix.install}}
+      run: |
+        sudo apt-get update
+        sudo apt-get install ${{matrix.install}}
+
     - name: Determine number of cpus on Linux
       if: startsWith(matrix.os, 'ubuntu')
       run: echo "num_cpus=$(nproc)" >> $GITHUB_ENV # TODO use set-output instead