diff --git a/.github/workflows/test_and_build.yml b/.github/workflows/test_and_build.yml
index 58abc8e..b52e99c 100644
--- a/.github/workflows/test_and_build.yml
+++ b/.github/workflows/test_and_build.yml
@@ -26,7 +26,7 @@ jobs:
         runs-on: ${{ matrix.os }}
         strategy:
             matrix:
-                os: [ubuntu-latest, macos-latest]
+                os: [ubuntu-20.04, macos-latest]
                 python-version: [3.7]
 
         steps:
diff --git a/conda_recipe/xspec-modelsonly/meta.yaml b/conda_recipe/xspec-modelsonly/meta.yaml
index 787d4aa..cf310c9 100644
--- a/conda_recipe/xspec-modelsonly/meta.yaml
+++ b/conda_recipe/xspec-modelsonly/meta.yaml
@@ -18,8 +18,8 @@ requirements:
       #- ccfits==2.5 # [py2k] 
       - cfitsio==3.410 # [py2k] 
       - gfortran_osx-64 # [osx]
-      - {{ compiler('c') }} # [linux]
-      - {{ compiler('cxx') }} # [linux]
+      #- {{ compiler('c') }} # [linux]
+      #- {{ compiler('cxx') }} # [linux]
       - {{ compiler('fortran') }} # [linux]
       - libgfortran>=3.0,<4.0 # [osx]
       - libgfortran-ng==7.5.0 # [linux]