diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 442cd814..13b00d01 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -31,6 +31,7 @@ jobs:
 
           - name: macos-apple-clang
             os: macos-latest
+            compiler-cppstd: "gnu17"
 
           - name: windows-msvc-19
             os: windows-2019
@@ -69,10 +70,13 @@ jobs:
         run: |
           conan profile detect --force
           if [ "${{ matrix.compiler-name-conan }}" != "" ]; then
-            sed -i 's/compiler=.*/compiler=${{ matrix.compiler-name-conan }}/g' ~/.conan2/profiles/default
+            sed -i.bak -e 's/compiler=.*/compiler=${{ matrix.compiler-name-conan }}/g' ~/.conan2/profiles/default
           fi
           if [ "${{ matrix.compiler-version }}" != "" ]; then
-            sed -i 's/compiler.version=[0-9]\+/compiler.version=${{ matrix.compiler-version }}/g' ~/.conan2/profiles/default
+            sed -i.bak -e 's/compiler.version=[0-9]\+/compiler.version=${{ matrix.compiler-version }}/g' ~/.conan2/profiles/default
+          fi
+          if [ "${{ matrix.compiler-cppstd }}" != "" ]; then
+            sed -i.bak -e 's/compiler.cppstd=gnu[0-9]\+/compiler.cppstd=${{ matrix.compiler-cppstd }}/g' ~/.conan2/profiles/default
           fi
         shell: bash
 
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 77313471..5faa0b8d 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -14,7 +14,6 @@ project(
   LANGUAGES CXX)
 
 include(GNUInstallDirs)
-include(CTest)
 
 option(SI_INSTALL_LIBRARY
        "Enable installing of SI library into default locations"
@@ -44,7 +43,9 @@ target_include_directories(
 
 target_compile_features(SI INTERFACE cxx_std_17)
 
-if(BUILD_TESTING AND SI_BUILD_TESTING)
+if(SI_BUILD_TESTING)
+  enable_testing()
+
   include(Catch)
   add_subdirectory(test)
 endif()
diff --git a/test/compilation-tests.sh b/test/compilation-tests.sh
index 41cf08f1..6c036394 100755
--- a/test/compilation-tests.sh
+++ b/test/compilation-tests.sh
@@ -10,15 +10,15 @@ buildSingleTarget()
     if [ "${2}" == "DEFAULTBUILD" ]; then
         cmake ${ROOT_DIR}/test/src/compilation_tests/ -B${BUILD_DIR} -DCMAKE_PREFIX_PATH=${BUILD_DIR} -DCMAKE_INSTALL_PREFIX:PATH=${INSTALL_PATH} -DCMAKE_BUILD_TYPE=Release -G Ninja > /dev/null
         assertEquals "Configuration successful" 0 $?
-        
+
     else
         cmake ${ROOT_DIR}/test/src/compilation_tests/ -B${BUILD_DIR} -DCMAKE_PREFIX_PATH=${BUILD_DIR} -DCMAKE_INSTALL_PREFIX:PATH=${INSTALL_PATH} -DCMAKE_BUILD_TYPE=Release -DCMAKE_CXX_FLAGS="-DSI_DISABLE_IMPLICIT_RATIO_CONVERSION" -G Ninja > /dev/null
         assertEquals "Configuration successful" 0 $?
     fi
-    
+
     cmake --build ${BUILD_DIR} --config Release --target $1 > /dev/null
     RESULT=$?
-    
+
     if [ "${3}" == "PASS" ]; then
         assertEquals "Building successful" 0 $RESULT
     else
@@ -27,14 +27,14 @@ buildSingleTarget()
 }
 
 oneTimeSetUp(){
-    
+
     BUILD_DIR=$(mktemp -d)
     conan install . --output-folder=${BUILD_DIR} --build=missing --settings=build_type=Release 2>&1> /dev/null
-    
+
     # install SI
-    cmake ${ROOT_DIR} -B${BUILD_DIR} -DCMAKE_PREFIX_PATH=${BUILD_DIR} -DCMAKE_INSTALL_PREFIX:PATH=${INSTALL_PATH} -DBUILD_TESTING=off -DCMAKE_BUILD_TYPE=Release -G Ninja > /dev/null
+    cmake ${ROOT_DIR} -B${BUILD_DIR} -DCMAKE_PREFIX_PATH=${BUILD_DIR} -DCMAKE_INSTALL_PREFIX:PATH=${INSTALL_PATH} -DSI_BUILD_TESTING=OFF -DCMAKE_BUILD_TYPE=Release -G Ninja > /dev/null
     cmake --build ${BUILD_DIR} --config Release --target install > /dev/null
-    
+
     if [ -d ${BUILD_DIR} ]; then
         rm -rf ${BUILD_DIR}
     fi
@@ -52,7 +52,7 @@ tearDown(){
 }
 
 testSISelfSuccessfulCompilationWhenDefaultInvocation() {
-    
+
     cmake ${ROOT_DIR} -B${BUILD_DIR} -DCMAKE_BUILD_TYPE=Release -DCMAKE_PREFIX_PATH=${BUILD_DIR} -G Ninja > /dev/null
     assertEquals "Configuration successful" 0 $?
     cmake --build ${BUILD_DIR} --config Release > /dev/null
@@ -60,7 +60,7 @@ testSISelfSuccessfulCompilationWhenDefaultInvocation() {
 }
 
 testSISelfFailedCompilationWhenImplicitConversionDisabled() {
-    
+
     cmake ${ROOT_DIR} -B${BUILD_DIR} -DCMAKE_BUILD_TYPE=Release -DCMAKE_PREFIX_PATH=${BUILD_DIR} -DCMAKE_CXX_FLAGS="-DSI_DISABLE_IMPLICIT_RATIO_CONVERSION" -G Ninja > /dev/null
     assertEquals "Configuration successful" 0 $?
     cmake --build ${BUILD_DIR} --config Release
@@ -347,4 +347,4 @@ testCompilationSucceedsWhenNumberParserDoesNotOverflow()
 
 
 # Load shUnit2.
-. shunit2
\ No newline at end of file
+. shunit2
diff --git a/test/installation-tests.sh b/test/installation-tests.sh
index 2cc4d551..5ed4deeb 100755
--- a/test/installation-tests.sh
+++ b/test/installation-tests.sh
@@ -17,11 +17,11 @@ tearDown() {
     if [ -d ${SI_BUILD_DIR} ]; then
         rm -rf ${SI_BUILD_DIR}
     fi
-    
+
     if [ -d ${INSTALL_PATH} ]; then
         rm -rf ${INSTALL_PATH}
     fi
-    
+
     if [ -d ${BUILD_DIR} ]; then
         rm -rf ${BUILD_DIR}
     fi
@@ -29,30 +29,30 @@ tearDown() {
 
 testPureCmakeInstallation() {
     # install SI
-    cmake ${ROOT_DIR} -B${SI_BUILD_DIR} -DCMAKE_INSTALL_PREFIX:PATH=${INSTALL_PATH} -DBUILD_TESTING=off -DCMAKE_BUILD_TYPE=Release
+    cmake ${ROOT_DIR} -B${SI_BUILD_DIR} -DCMAKE_INSTALL_PREFIX:PATH=${INSTALL_PATH} -DSI_BUILD_TESTING=OFF -DCMAKE_BUILD_TYPE=Release
     cmake --build ${SI_BUILD_DIR} --config Release --target install
     assertEquals "Installation build successful" 0 $?
     cmake ${ROOT_DIR}/test/installation-tests -B${BUILD_DIR} -DCMAKE_INSTALL_PREFIX:PATH=${INSTALL_PATH}
     cmake --build ${BUILD_DIR}
     assertEquals "build against installation successful" 0 $?
-    
+
 }
 
 testPureCmakeInstallationWithInstallOptionTurnedOff() {
     # install SI
-    cmake ${ROOT_DIR} -B${SI_BUILD_DIR} -DCMAKE_INSTALL_PREFIX:PATH=${INSTALL_PATH} -DBUILD_TESTING=off -DSI_INSTALL_LIBRARY=OFF -DCMAKE_BUILD_TYPE=Release
+    cmake ${ROOT_DIR} -B${SI_BUILD_DIR} -DCMAKE_INSTALL_PREFIX:PATH=${INSTALL_PATH} -DSI_BUILD_TESTING=OFF -DSI_INSTALL_LIBRARY=OFF -DCMAKE_BUILD_TYPE=Release
     cmake --build ${SI_BUILD_DIR} --config Release --target install
     assertNotEquals "Installation build successful" 0 $?
-    
+
     DIRECTORY_CONTENTS=$(ls -A ${INSTALL_PATH})
     EMPTY=""
     assertEquals "Installation directory is empty" "${EMPTY}" "${DIRECTORY_CONTENTS}"
-    
+
 }
 
 testCpackInstallation() {
     # install SI
-    cmake ${ROOT_DIR} -B${SI_BUILD_DIR} -DCPACK_PACKAGE_FILE_NAME=install-SI -DBUILD_TESTING=off -DCMAKE_BUILD_TYPE=Release
+    cmake ${ROOT_DIR} -B${SI_BUILD_DIR} -DCPACK_PACKAGE_FILE_NAME=install-SI -DSI_BUILD_TESTING=OFF -DCMAKE_BUILD_TYPE=Release
     cmake --build ${SI_BUILD_DIR} --config Release --target package
     assertEquals "Installation build successful" 0 $?
     if [ "${OS_NAME}" = "Linux" ] || [ "${OS_NAME}" = "Darwin" ]; then
@@ -63,13 +63,13 @@ testCpackInstallation() {
         # echo "done"
         return
     fi
-    
+
     assertEquals "Installation script successful" 0 $?
-    
+
     cmake ${ROOT_DIR}/test/installation-tests -B${BUILD_DIR} -DCMAKE_INSTALL_PREFIX:PATH=${INSTALL_PATH}
     cmake --build ${BUILD_DIR}
     assertEquals "build against installation successful" 0 $?
-    
+
 }
 
 
@@ -78,7 +78,7 @@ testUsageAsSubdirectory() {
     cmake ${ROOT_DIR}/test/installation-test-subdirectory -B${BUILD_DIR} -DCMAKE_BUILD_TYPE=Release
     cmake --build ${BUILD_DIR}
     assertEquals "build against installation successful" 0 $?
-    
+
 }
 
 # Load shUnit2.
diff --git a/test/version-consistency.sh b/test/version-consistency.sh
index 9e700013..1d6dce41 100755
--- a/test/version-consistency.sh
+++ b/test/version-consistency.sh
@@ -24,7 +24,7 @@ testVersionNumberConsistency() {
     CHANGELOG_VERSION=$(sed -n -E '/## [0-9]+\.[0-9]+\.[0-9]+/p' ${ROOT_DIR}/CHANGELOG.md | head -1 | grep -E -o '[0-9]+\.[0-9]+\.[0-9]+')
     ORIG_DIR=$(pwd)
 
-    cmake ${ROOT_DIR} -B${SI_BUILD_DIR} -DBUILD_TESTING=off -DCMAKE_BUILD_TYPE=Debug >/dev/null
+    cmake ${ROOT_DIR} -B${SI_BUILD_DIR} -DSI_BUILD_TESTING=OFF -DCMAKE_BUILD_TYPE=Debug >/dev/null
     cd ${SI_BUILD_DIR}
     CMAKE_VERSION=$(cmake --system-information | grep -E "VERSION:STATIC" | grep -E -o '[0-9]+\.[0-9]+\.[0-9]+')
     cd ${ORIG_DIR}