diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index eca65b45..9c52a44d 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -10,7 +10,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        os: [ubuntu-20.04]
+        os: [ubuntu-18.04, ubuntu-20.04]
 
     steps:
     - uses: actions/checkout@v2
diff --git a/test/etl_profile.h b/test/etl_profile.h
index 64f6f7d4..d7c96a1f 100644
--- a/test/etl_profile.h
+++ b/test/etl_profile.h
@@ -103,6 +103,10 @@ SOFTWARE.
   #error THE UNIT TESTS REQUIRE C++17 SUPPORT
 #endif
 
+#if defined(ETL_COMPILER_GCC) && (ETL_COMPILER_VERSION < 8)
+  #define ETL_TEMPLATE_DEDUCTION_GUIDE_TESTS_DISABLED
+#endif
+
 #include "../include/etl/profiles/determine_development_os.h"
 
 #if defined(ETL_DEVELOPMENT_OS_WINDOWS)