diff --git a/clean_build.sh b/clean_build.sh
index fc1065a5..826a270c 100755
--- a/clean_build.sh
+++ b/clean_build.sh
@@ -1,28 +1,52 @@
-#!/bin/sh
-cd "$(dirname $0)" || exit 1
+#!/bin/bash
+
+set -eu # we set this to catch errors and terminate
+
+cd "$(dirname "$0")" || exit 1
+
 # some environments have cmake v2 as 'cmake' and v3 as 'cmake3'
 # check for cmake3 first then fallback to just cmake
-B_CMAKE=`type cmake3 2>/dev/null`
-if [ $? -eq 0 ]; then
-    B_CMAKE=`echo $B_CMAKE | cut -d' ' -f3`
+
+if type cmake3 2>/dev/null; then
+    B_CMAKE=$(command -v "$(echo "$B_CMAKE" | cut -d' ' -f3)")
 else
-    B_CMAKE=cmake
+    B_CMAKE=$(command -v cmake)
 fi
+
 # default build configuration
 B_BUILD_TYPE=${B_BUILD_TYPE:-Debug}
-if [ "$(uname)" = "Darwin" ]; then
+
+if [ "$(uname -s)" = "Darwin" ]; then
     # OSX needs a lot of extra help, poor thing
     # run the osx_environment.sh script to fix paths
-    . ./osx_environment.sh
+    if [ -f "./osx_environment.sh" ]; then
+       . ./osx_environment.sh
+    fi
     B_CMAKE_FLAGS="-DCMAKE_OSX_SYSROOT=$(xcode-select --print-path)/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk -DCMAKE_OSX_DEPLOYMENT_TARGET=10.9 $B_CMAKE_FLAGS"
 fi
+
 # allow local customizations to build environment
-[ -r ./build_env.sh ] && . ./build_env.sh
-B_CMAKE_FLAGS="-DCMAKE_BUILD_TYPE=$B_BUILD_TYPE $B_CMAKE_FLAGS"
+if [ -f "./build_env.sh" ]; then
+    . ./build_env.sh
+fi
+
+set +eu # disable this temporarily
+if [ -n "${B_CMAKE_FLAGS}" ]; then
+    B_CMAKE_FLAGS="-DCMAKE_BUILD_TYPE=$B_BUILD_TYPE ${B_CMAKE_FLAGS}"
+else
+    B_CMAKE_FLAGS="-DCMAKE_BUILD_TYPE=$B_BUILD_TYPE"
+fi
+set -eu # enable this
+
 rm -rf build
 mkdir build || exit 1
 cd build || exit 1
-echo Starting Barrier $B_BUILD_TYPE build...
-$B_CMAKE $B_CMAKE_FLAGS .. || exit 1
+
+echo "Starting Barrier build..."
+echo "Build type: ${B_BUILD_TYPE}"
+
+"$B_CMAKE" "$B_CMAKE_FLAGS" .. || exit 1
+
 make || exit 1
-echo "Build completed successfully"
+
+echo "Build completed successfully."
diff --git a/osx_environment.sh b/osx_environment.sh
index 09fa3479..2073801c 100644
--- a/osx_environment.sh
+++ b/osx_environment.sh
@@ -11,7 +11,7 @@ function check_dir_exists() {
     fi
 }
 
-if [ ! $BARRIER_BUILD_ENV ]; then
+if [ ! "$BARRIER_BUILD_ENV" ]; then
     check_dir_exists '/Applications/Xcode.app' 'Xcode'
 
     printf "Modifying environment for Barrier build...\n"