diff --git a/Dockerfile b/Dockerfile
index dd5b4c26..dd947361 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -36,11 +36,11 @@ RUN apt -y install sudo zsh
 RUN apt -y dist-upgrade
 RUN mkdir -p build-sol2/Debug build-sol2/Release
 RUN chmod +x /sol2/scripts/preparation.linux.sh
-RUN ["/usr/bin/env", "zsh", "-c", "./sol2/scripts/preparation.linux.sh"]
+RUN ["/usr/bin/env", "zsh", "-c", "-x", "./sol2/scripts/preparation.linux.sh"]
 # CMD/ENTRYPOINT is different from RUN
 # these are done on a per-instantiation and essentially describe
 # the DEFAULT behavior of this container when its started, not what state it
 # gets "saved" in...
 # it only runs the last CMD/ENTRYPOINT as the default behavior:
 # multiple CMDs will not be respected
-CMD ["/usr/bin/env", "zsh", "-c", "chmod +x /sol2/scripts/run.linux.sh && ./sol2/scripts/run.linux.sh"]
+CMD ["/usr/bin/env", "zsh", "-c", "-x", "chmod +x /sol2/scripts/run.linux.sh && ./sol2/scripts/run.linux.sh"]
diff --git a/scripts/preparation.linux.sh b/scripts/preparation.linux.sh
index f9e03015..b0a0aa99 100644
--- a/scripts/preparation.linux.sh
+++ b/scripts/preparation.linux.sh
@@ -54,6 +54,7 @@ sudo apt -y install build-essential zsh ninja-build libreadline6 libreadline6-de
 if [ "$LLVM_VERSION" ]
 then
 	# get and use LLVM
+	echo "========== detected LLVM_VERSION, attempting to install llvm version $LLVM_VERSION =========="
 	wget http://llvm.org/releases/$LLVM_VERSION/clang+llvm-$LLVM_VERSION-x86_64-linux-gnu-ubuntu-16.04.tar.xz -O $LLVM_ARCHIVE_PATH
 	mkdir ~/clang-$LLVM_VERSION
 	tar xf $LLVM_ARCHIVE_PATH -C $HOME/clang-$LLVM_VERSION --strip-components 1
@@ -63,6 +64,7 @@ then
 elif [ "$GCC_VERSION" ]
 then
 	# get and use GCC version that we desire
+	echo "========== detected GCC_VERSION, attempting to install gcc version $GCC_VERSION =========="
 	sudo add-apt-repository ppa:ubuntu-toolchain-r/test -y
 	sudo apt update
 	sudo apt dist-upgrade
diff --git a/scripts/run.linux.sh b/scripts/run.linux.sh
index 05d88292..3208d520 100644
--- a/scripts/run.linux.sh
+++ b/scripts/run.linux.sh
@@ -1,12 +1,22 @@
+if [ "$LLVM_VERSION" ]
+then
+	build_type=-DCMAKE_CXX_COMPILER\=clang++ -DCMAKE_C_COMPILER\=clang;
+elif [ "$GCC_VERSION" ]
+then
+	build_type=-DCMAKE_CXX_COMPILER\=g++ -DCMAKE_C_COMPILER\=gcc;
+else
+	build_type=-DCMAKE_CXX_COMPILER\=g++ -DCMAKE_C_COMPILER\=gcc;
+fi
+
 cd build-sol2
 cd Debug
-cmake ../../sol2 -G Ninja -DCMAKE_BUILD_TYPE=Debug   -DLUA_VERSION="${LUA_VERSION}" -DBUILD_LUA=ON -DBUILD_LUA_AS_DLL=OFF -DTESTS=ON -DEXAMPLES=ON -DSINGLE=ON -DTESTS_EXAMPLES=ON -DTESTS_SINGLE=ON
+cmake ../../sol2 -G Ninja -DCMAKE_BUILD_TYPE=Debug $build_type -DLUA_VERSION="${LUA_VERSION}" -DBUILD_LUA=ON -DBUILD_LUA_AS_DLL=OFF -DTESTS=ON -DEXAMPLES=ON -DSINGLE=ON -DTESTS_EXAMPLES=ON -DTESTS_SINGLE=ON
 cmake --build . --config Debug
 ctest -C Debug
 cd ..
 
 cd Release
-cmake ../../sol2 -G Ninja -DCMAKE_BUILD_TYPE=Release -DLUA_VERSION="${LUA_VERSION}" -DBUILD_LUA=ON -DBUILD_LUA_AS_DLL=OFF -DTESTS=ON -DEXAMPLES=ON -DSINGLE=ON -DTESTS_EXAMPLES=ON -DTESTS_SINGLE=ON
+cmake ../../sol2 -G Ninja -DCMAKE_BUILD_TYPE=Release $build_type -DLUA_VERSION="${LUA_VERSION}" -DBUILD_LUA=ON -DBUILD_LUA_AS_DLL=OFF -DTESTS=ON -DEXAMPLES=ON -DSINGLE=ON -DTESTS_EXAMPLES=ON -DTESTS_SINGLE=ON
 cmake --build . --config Release
 ctest -C Release
 cd ..