diff --git a/pkgs/development/compilers/swift/swiftpm/setup-hook.sh b/pkgs/development/compilers/swift/swiftpm/setup-hook.sh
index 160fbb1ccca3..260d874ebfd7 100644
--- a/pkgs/development/compilers/swift/swiftpm/setup-hook.sh
+++ b/pkgs/development/compilers/swift/swiftpm/setup-hook.sh
@@ -1,3 +1,5 @@
+# shellcheck shell=bash
+
 # Build using 'swift-build'.
 swiftpmBuildPhase() {
     runHook preBuild
@@ -8,10 +10,10 @@ swiftpmBuildPhase() {
     fi
 
     local flagsArray=(
-        -j $buildCores
+        -j "$buildCores"
         -c "${swiftpmBuildConfig-release}"
-        $swiftpmFlags "${swiftpmFlagsArray[@]}"
     )
+    concatTo flagsArray swiftpmFlags swiftpmFlagsArray
 
     echoCmd 'build flags' "${flagsArray[@]}"
     TERM=dumb swift-build "${flagsArray[@]}"
@@ -33,10 +35,10 @@ swiftpmCheckPhase() {
     fi
 
     local flagsArray=(
-        -j $buildCores
+        -j "$buildCores"
         -c "${swiftpmBuildConfig-release}"
-        $swiftpmFlags "${swiftpmFlagsArray[@]}"
     )
+    concatTo flagsArray swiftpmFlags swiftpmFlagsArray
 
     echoCmd 'check flags' "${flagsArray[@]}"
     TERM=dumb swift-test "${flagsArray[@]}"
@@ -53,8 +55,8 @@ fi
 swiftpmBinPath() {
     local flagsArray=(
         -c "${swiftpmBuildConfig-release}"
-        $swiftpmFlags "${swiftpmFlagsArray[@]}"
     )
+    concatTo flagsArray swiftpmFlags swiftpmFlagsArray
 
     swift-build --show-bin-path "${flagsArray[@]}"
 }
diff --git a/pkgs/development/cuda-modules/setup-hooks/setup-cuda-hook.sh b/pkgs/development/cuda-modules/setup-hooks/setup-cuda-hook.sh
index 6e57c7b1072e..7799d72873a0 100644
--- a/pkgs/development/cuda-modules/setup-hooks/setup-cuda-hook.sh
+++ b/pkgs/development/cuda-modules/setup-hooks/setup-cuda-hook.sh
@@ -54,7 +54,8 @@ setupCUDAToolkit_ROOT() {
         fi
     done
 
-    export cmakeFlags+=" -DCUDAToolkit_INCLUDE_DIR=$CUDAToolkit_INCLUDE_DIR -DCUDAToolkit_ROOT=$CUDAToolkit_ROOT"
+    appendToVar cmakeFlags "-DCUDAToolkit_INCLUDE_DIR=$CUDAToolkit_INCLUDE_DIR"
+    appendToVar cmakeFlags "-DCUDAToolkit_ROOT=$CUDAToolkit_ROOT"
 }
 preConfigureHooks+=(setupCUDAToolkit_ROOT)
 
@@ -72,8 +73,8 @@ setupCUDAToolkitCompilers() {
     # https://cmake.org/cmake/help/latest/envvar/CUDAHOSTCXX.html
     # https://cmake.org/cmake/help/latest/variable/CMAKE_CUDA_HOST_COMPILER.html
 
-    export cmakeFlags+=" -DCUDA_HOST_COMPILER=@ccFullPath@"
-    export cmakeFlags+=" -DCMAKE_CUDA_HOST_COMPILER=@ccFullPath@"
+    appendToVar cmakeFlags "-DCUDA_HOST_COMPILER=@ccFullPath@"
+    appendToVar cmakeFlags "-DCMAKE_CUDA_HOST_COMPILER=@ccFullPath@"
 
     # For non-CMake projects:
     # We prepend --compiler-bindir to nvcc flags.
@@ -85,7 +86,7 @@ setupCUDAToolkitCompilers() {
       export CUDAHOSTCXX="@ccFullPath@";
     fi
 
-    export NVCC_PREPEND_FLAGS+=" --compiler-bindir=@ccRoot@/bin"
+    appendToVar NVCC_PREPEND_FLAGS "--compiler-bindir=@ccRoot@/bin"
 
     # NOTE: We set -Xfatbin=-compress-all, which reduces the size of the compiled
     #   binaries. If binaries grow over 2GB, they will fail to link. This is a problem for us, as
@@ -94,7 +95,7 @@ setupCUDAToolkitCompilers() {
     #
     # @SomeoneSerge: original comment was made by @ConnorBaker in .../cudatoolkit/common.nix
     if [[ -z "${dontCompressFatbin-}" ]]; then
-        export NVCC_PREPEND_FLAGS+=" -Xfatbin=-compress-all"
+        appendToVar NVCC_PREPEND_FLAGS "-Xfatbin=-compress-all"
     fi
 }
 preConfigureHooks+=(setupCUDAToolkitCompilers)
diff --git a/pkgs/development/libraries/kde-frameworks/extra-cmake-modules/setup-hook.sh b/pkgs/development/libraries/kde-frameworks/extra-cmake-modules/setup-hook.sh
index 8d86ab1d54ad..e576dbb4ec73 100644
--- a/pkgs/development/libraries/kde-frameworks/extra-cmake-modules/setup-hook.sh
+++ b/pkgs/development/libraries/kde-frameworks/extra-cmake-modules/setup-hook.sh
@@ -6,53 +6,53 @@ addEnvHooks "$targetOffset" ecmEnvHook
 
 ecmPostHook() {
     # Because we need to use absolute paths here, we must set *all* the paths.
-    cmakeFlags+=" -DKDE_INSTALL_EXECROOTDIR=${!outputBin}"
-    cmakeFlags+=" -DKDE_INSTALL_BINDIR=${!outputBin}/bin"
-    cmakeFlags+=" -DKDE_INSTALL_SBINDIR=${!outputBin}/sbin"
-    cmakeFlags+=" -DKDE_INSTALL_LIBDIR=${!outputLib}/lib"
-    cmakeFlags+=" -DKDE_INSTALL_LIBEXECDIR=${!outputLib}/libexec"
-    cmakeFlags+=" -DKDE_INSTALL_CMAKEPACKAGEDIR=${!outputDev}/lib/cmake"
-    cmakeFlags+=" -DKDE_INSTALL_INCLUDEDIR=${!outputInclude}/include"
-    cmakeFlags+=" -DKDE_INSTALL_LOCALSTATEDIR=/var"
-    cmakeFlags+=" -DKDE_INSTALL_DATAROOTDIR=${!outputBin}/share"
-    cmakeFlags+=" -DKDE_INSTALL_DATADIR=${!outputBin}/share"
-    cmakeFlags+=" -DKDE_INSTALL_DOCBUNDLEDIR=${!outputBin}/share/doc/HTML"
-    cmakeFlags+=" -DKDE_INSTALL_KCFGDIR=${!outputBin}/share/config.kcfg"
-    cmakeFlags+=" -DKDE_INSTALL_KCONFUPDATEDIR=${!outputBin}/share/kconf_update"
-    cmakeFlags+=" -DKDE_INSTALL_KSERVICES5DIR=${!outputBin}/share/kservices5"
-    cmakeFlags+=" -DKDE_INSTALL_KSERVICETYPES5DIR=${!outputBin}/share/kservicetypes5"
-    cmakeFlags+=" -DKDE_INSTALL_KXMLGUI5DIR=${!outputBin}/share/kxmlgui5"
-    cmakeFlags+=" -DKDE_INSTALL_KNOTIFY5RCDIR=${!outputBin}/share/knotifications5"
-    cmakeFlags+=" -DKDE_INSTALL_ICONDIR=${!outputBin}/share/icons"
-    cmakeFlags+=" -DKDE_INSTALL_LOCALEDIR=${!outputLib}/share/locale"
-    cmakeFlags+=" -DKDE_INSTALL_SOUNDDIR=${!outputBin}/share/sounds"
-    cmakeFlags+=" -DKDE_INSTALL_TEMPLATEDIR=${!outputBin}/share/templates"
-    cmakeFlags+=" -DKDE_INSTALL_WALLPAPERDIR=${!outputBin}/share/wallpapers"
-    cmakeFlags+=" -DKDE_INSTALL_APPDIR=${!outputBin}/share/applications"
-    cmakeFlags+=" -DKDE_INSTALL_DESKTOPDIR=${!outputBin}/share/desktop-directories"
-    cmakeFlags+=" -DKDE_INSTALL_MIMEDIR=${!outputBin}/share/mime/packages"
-    cmakeFlags+=" -DKDE_INSTALL_METAINFODIR=${!outputBin}/share/appdata"
-    cmakeFlags+=" -DKDE_INSTALL_MANDIR=${!outputBin}/share/man"
-    cmakeFlags+=" -DKDE_INSTALL_INFODIR=${!outputBin}/share/info"
-    cmakeFlags+=" -DKDE_INSTALL_DBUSDIR=${!outputBin}/share/dbus-1"
-    cmakeFlags+=" -DKDE_INSTALL_DBUSINTERFACEDIR=${!outputBin}/share/dbus-1/interfaces"
-    cmakeFlags+=" -DKDE_INSTALL_DBUSSERVICEDIR=${!outputBin}/share/dbus-1/services"
-    cmakeFlags+=" -DKDE_INSTALL_DBUSSYSTEMSERVICEDIR=${!outputBin}/share/dbus-1/system-services"
-    cmakeFlags+=" -DKDE_INSTALL_SYSCONFDIR=${!outputBin}/etc"
-    cmakeFlags+=" -DKDE_INSTALL_CONFDIR=${!outputBin}/etc/xdg"
-    cmakeFlags+=" -DKDE_INSTALL_AUTOSTARTDIR=${!outputBin}/etc/xdg/autostart"
+    appendToVar cmakeFlags "-DKDE_INSTALL_EXECROOTDIR=${!outputBin}"
+    appendToVar cmakeFlags "-DKDE_INSTALL_BINDIR=${!outputBin}/bin"
+    appendToVar cmakeFlags "-DKDE_INSTALL_SBINDIR=${!outputBin}/sbin"
+    appendToVar cmakeFlags "-DKDE_INSTALL_LIBDIR=${!outputLib}/lib"
+    appendToVar cmakeFlags "-DKDE_INSTALL_LIBEXECDIR=${!outputLib}/libexec"
+    appendToVar cmakeFlags "-DKDE_INSTALL_CMAKEPACKAGEDIR=${!outputDev}/lib/cmake"
+    appendToVar cmakeFlags "-DKDE_INSTALL_INCLUDEDIR=${!outputInclude}/include"
+    appendToVar cmakeFlags "-DKDE_INSTALL_LOCALSTATEDIR=/var"
+    appendToVar cmakeFlags "-DKDE_INSTALL_DATAROOTDIR=${!outputBin}/share"
+    appendToVar cmakeFlags "-DKDE_INSTALL_DATADIR=${!outputBin}/share"
+    appendToVar cmakeFlags "-DKDE_INSTALL_DOCBUNDLEDIR=${!outputBin}/share/doc/HTML"
+    appendToVar cmakeFlags "-DKDE_INSTALL_KCFGDIR=${!outputBin}/share/config.kcfg"
+    appendToVar cmakeFlags "-DKDE_INSTALL_KCONFUPDATEDIR=${!outputBin}/share/kconf_update"
+    appendToVar cmakeFlags "-DKDE_INSTALL_KSERVICES5DIR=${!outputBin}/share/kservices5"
+    appendToVar cmakeFlags "-DKDE_INSTALL_KSERVICETYPES5DIR=${!outputBin}/share/kservicetypes5"
+    appendToVar cmakeFlags "-DKDE_INSTALL_KXMLGUI5DIR=${!outputBin}/share/kxmlgui5"
+    appendToVar cmakeFlags "-DKDE_INSTALL_KNOTIFY5RCDIR=${!outputBin}/share/knotifications5"
+    appendToVar cmakeFlags "-DKDE_INSTALL_ICONDIR=${!outputBin}/share/icons"
+    appendToVar cmakeFlags "-DKDE_INSTALL_LOCALEDIR=${!outputLib}/share/locale"
+    appendToVar cmakeFlags "-DKDE_INSTALL_SOUNDDIR=${!outputBin}/share/sounds"
+    appendToVar cmakeFlags "-DKDE_INSTALL_TEMPLATEDIR=${!outputBin}/share/templates"
+    appendToVar cmakeFlags "-DKDE_INSTALL_WALLPAPERDIR=${!outputBin}/share/wallpapers"
+    appendToVar cmakeFlags "-DKDE_INSTALL_APPDIR=${!outputBin}/share/applications"
+    appendToVar cmakeFlags "-DKDE_INSTALL_DESKTOPDIR=${!outputBin}/share/desktop-directories"
+    appendToVar cmakeFlags "-DKDE_INSTALL_MIMEDIR=${!outputBin}/share/mime/packages"
+    appendToVar cmakeFlags "-DKDE_INSTALL_METAINFODIR=${!outputBin}/share/appdata"
+    appendToVar cmakeFlags "-DKDE_INSTALL_MANDIR=${!outputBin}/share/man"
+    appendToVar cmakeFlags "-DKDE_INSTALL_INFODIR=${!outputBin}/share/info"
+    appendToVar cmakeFlags "-DKDE_INSTALL_DBUSDIR=${!outputBin}/share/dbus-1"
+    appendToVar cmakeFlags "-DKDE_INSTALL_DBUSINTERFACEDIR=${!outputBin}/share/dbus-1/interfaces"
+    appendToVar cmakeFlags "-DKDE_INSTALL_DBUSSERVICEDIR=${!outputBin}/share/dbus-1/services"
+    appendToVar cmakeFlags "-DKDE_INSTALL_DBUSSYSTEMSERVICEDIR=${!outputBin}/share/dbus-1/system-services"
+    appendToVar cmakeFlags "-DKDE_INSTALL_SYSCONFDIR=${!outputBin}/etc"
+    appendToVar cmakeFlags "-DKDE_INSTALL_CONFDIR=${!outputBin}/etc/xdg"
+    appendToVar cmakeFlags "-DKDE_INSTALL_AUTOSTARTDIR=${!outputBin}/etc/xdg/autostart"
 
     if [ "$(uname)" = "Darwin" ]; then
-        cmakeFlags+=" -DKDE_INSTALL_BUNDLEDIR=${!outputBin}/Applications/KDE"
+        appendToVar cmakeFlags "-DKDE_INSTALL_BUNDLEDIR=${!outputBin}/Applications/KDE"
     fi
 
     if [ -n "${qtPluginPrefix-}" ]; then
-        cmakeFlags+=" -DKDE_INSTALL_QTPLUGINDIR=${!outputBin}/$qtPluginPrefix"
-        cmakeFlags+=" -DKDE_INSTALL_PLUGINDIR=${!outputBin}/$qtPluginPrefix"
+        appendToVar cmakeFlags "-DKDE_INSTALL_QTPLUGINDIR=${!outputBin}/$qtPluginPrefix"
+        appendToVar cmakeFlags "-DKDE_INSTALL_PLUGINDIR=${!outputBin}/$qtPluginPrefix"
     fi
 
     if [ -n "${qtQmlPrefix-}" ]; then
-        cmakeFlags+=" -DKDE_INSTALL_QMLDIR=${!outputBin}/$qtQmlPrefix"
+        appendToVar cmakeFlags "-DKDE_INSTALL_QMLDIR=${!outputBin}/$qtQmlPrefix"
     fi
 }
 postHooks+=(ecmPostHook)
diff --git a/pkgs/development/tools/build-managers/gradle/setup-hook.sh b/pkgs/development/tools/build-managers/gradle/setup-hook.sh
index a16742414b12..6c9c927f0c45 100644
--- a/pkgs/development/tools/build-managers/gradle/setup-hook.sh
+++ b/pkgs/development/tools/build-managers/gradle/setup-hook.sh
@@ -29,7 +29,9 @@ gradleConfigureHook() {
 }
 
 gradle() {
-    command gradle $gradleFlags "${gradleFlagsArray[@]}" "$@"
+    local flagsArray=()
+    concatTo flagsArray gradleFlags gradleFlagsArray
+    command gradle "${flagsArray[@]}" "$@"
 }
 
 gradleBuildPhase() {
diff --git a/pkgs/development/tools/xcbuild/setup-hook.sh b/pkgs/development/tools/xcbuild/setup-hook.sh
index f4b5abf2d8d3..cd8bfa59f1fb 100644
--- a/pkgs/development/tools/xcbuild/setup-hook.sh
+++ b/pkgs/development/tools/xcbuild/setup-hook.sh
@@ -3,9 +3,12 @@ xcbuildBuildPhase() {
 
     runHook preBuild
 
-    echo "running xcodebuild"
+    local flagsArray=()
+    concatTo flagsArray xcbuildFlags
 
-    xcodebuild SYMROOT=$PWD/Products OBJROOT=$PWD/Intermediates $xcbuildFlags build
+    echoCmd 'running xcodebuild' "${flagsArray[@]}"
+
+    xcodebuild SYMROOT=$PWD/Products OBJROOT=$PWD/Intermediates "${flagsArray[@]}" build
 
     runHook postBuild
 }
diff --git a/pkgs/kde/frameworks/extra-cmake-modules/ecm-hook.sh b/pkgs/kde/frameworks/extra-cmake-modules/ecm-hook.sh
index 1f60ba1aed92..c635816777f5 100644
--- a/pkgs/kde/frameworks/extra-cmake-modules/ecm-hook.sh
+++ b/pkgs/kde/frameworks/extra-cmake-modules/ecm-hook.sh
@@ -12,60 +12,60 @@ ecmPostHook() {
     # Because we need to use absolute paths here, we must set *all* the paths.
     # Keep this in sync with https://github.com/KDE/extra-cmake-modules/blob/master/kde-modules/KDEInstallDirs6.cmake
     if [ "$(uname)" = "Darwin" ]; then
-        cmakeFlags+=" -DKDE_INSTALL_BUNDLEDIR=${!outputBin}/Applications/KDE"
+        appendToVar cmakeFlags "-DKDE_INSTALL_BUNDLEDIR=${!outputBin}/Applications/KDE"
     fi
 
-    cmakeFlags+=" -DKDE_INSTALL_EXECROOTDIR=${!outputBin}"
-    cmakeFlags+=" -DKDE_INSTALL_BINDIR=${!outputBin}/bin"
-    cmakeFlags+=" -DKDE_INSTALL_SBINDIR=${!outputBin}/sbin"
-    cmakeFlags+=" -DKDE_INSTALL_LIBDIR=${!outputLib}/lib"
-    cmakeFlags+=" -DKDE_INSTALL_LIBEXECDIR=${!outputLib}/libexec"
-    cmakeFlags+=" -DKDE_INSTALL_CMAKEPACKAGEDIR=${!outputDev}/lib/cmake"
+    appendToVar cmakeFlags "-DKDE_INSTALL_EXECROOTDIR=${!outputBin}"
+    appendToVar cmakeFlags "-DKDE_INSTALL_BINDIR=${!outputBin}/bin"
+    appendToVar cmakeFlags "-DKDE_INSTALL_SBINDIR=${!outputBin}/sbin"
+    appendToVar cmakeFlags "-DKDE_INSTALL_LIBDIR=${!outputLib}/lib"
+    appendToVar cmakeFlags "-DKDE_INSTALL_LIBEXECDIR=${!outputLib}/libexec"
+    appendToVar cmakeFlags "-DKDE_INSTALL_CMAKEPACKAGEDIR=${!outputDev}/lib/cmake"
 
     if [ -n "${qtPluginPrefix-}" ]; then
-        cmakeFlags+=" -DKDE_INSTALL_QTPLUGINDIR=${!outputBin}/$qtPluginPrefix"
-        cmakeFlags+=" -DKDE_INSTALL_PLUGINDIR=${!outputBin}/$qtPluginPrefix"
+        appendToVar cmakeFlags "-DKDE_INSTALL_QTPLUGINDIR=${!outputBin}/$qtPluginPrefix"
+        appendToVar cmakeFlags "-DKDE_INSTALL_PLUGINDIR=${!outputBin}/$qtPluginPrefix"
     fi
 
     if [ -n "${qtQmlPrefix-}" ]; then
-        cmakeFlags+=" -DKDE_INSTALL_QMLDIR=${!outputBin}/$qtQmlPrefix"
+        appendToVar cmakeFlags "-DKDE_INSTALL_QMLDIR=${!outputBin}/$qtQmlPrefix"
     fi
 
-    cmakeFlags+=" -DKDE_INSTALL_INCLUDEDIR=${!outputInclude}/include"
-    cmakeFlags+=" -DKDE_INSTALL_LOCALSTATEDIR=/var"
-    cmakeFlags+=" -DKDE_INSTALL_SHAREDSTATEDIR=/com"  # ???
-    cmakeFlags+=" -DKDE_INSTALL_DATAROOTDIR=${!outputBin}/share"
-    cmakeFlags+=" -DKDE_INSTALL_DATADIR=${!outputBin}/share"
-    cmakeFlags+=" -DKDE_INSTALL_DOCBUNDLEDIR=${!outputBin}/share/doc/HTML"
-    cmakeFlags+=" -DKDE_INSTALL_KCFGDIR=${!outputBin}/share/config.kcfg"
-    cmakeFlags+=" -DKDE_INSTALL_KCONFUPDATEDIR=${!outputBin}/share/kconf_update"
-    cmakeFlags+=" -DKDE_INSTALL_KAPPTEMPLATESDIR=${!outputDev}/share/kdevappwizard/templates"
-    cmakeFlags+=" -DKDE_INSTALL_KFILETEMPLATESDIR=${!outputDev}/share/kdevfiletemplates/templates"
-    cmakeFlags+=" -DKDE_INSTALL_KXMLGUIDIR=${!outputBin}/share/kxmlgui5"  # Yes, this needs to be 5 and not 6. Don't ask.
-    cmakeFlags+=" -DKDE_INSTALL_KNOTIFYRCDIR=${!outputBin}/share/knotifications6"
-    cmakeFlags+=" -DKDE_INSTALL_ICONDIR=${!outputBin}/share/icons"
-    cmakeFlags+=" -DKDE_INSTALL_LOCALEDIR=${!outputLib}/share/locale"
-    cmakeFlags+=" -DKDE_INSTALL_SOUNDDIR=${!outputBin}/share/sounds"
-    cmakeFlags+=" -DKDE_INSTALL_TEMPLATEDIR=${!outputBin}/share/templates"
-    cmakeFlags+=" -DKDE_INSTALL_WALLPAPERDIR=${!outputBin}/share/wallpapers"
-    cmakeFlags+=" -DKDE_INSTALL_APPDIR=${!outputBin}/share/applications"
-    cmakeFlags+=" -DKDE_INSTALL_DESKTOPDIR=${!outputBin}/share/desktop-directories"
-    cmakeFlags+=" -DKDE_INSTALL_MIMEDIR=${!outputBin}/share/mime/packages"
-    cmakeFlags+=" -DKDE_INSTALL_METAINFODIR=${!outputBin}/share/appdata"
-    cmakeFlags+=" -DKDE_INSTALL_QTQCHDIR=${!outputLib}/share/doc/qch"
-    cmakeFlags+=" -DKDE_INSTALL_QCHDIR=${!outputLib}/share/doc/qch"
-    cmakeFlags+=" -DKDE_INSTALL_MANDIR=${!outputBin}/share/man"
-    cmakeFlags+=" -DKDE_INSTALL_INFODIR=${!outputBin}/share/info"
-    cmakeFlags+=" -DKDE_INSTALL_DBUSDIR=${!outputBin}/share/dbus-1"
-    cmakeFlags+=" -DKDE_INSTALL_DBUSINTERFACEDIR=${!outputBin}/share/dbus-1/interfaces"
-    cmakeFlags+=" -DKDE_INSTALL_DBUSSERVICEDIR=${!outputBin}/share/dbus-1/services"
-    cmakeFlags+=" -DKDE_INSTALL_DBUSSYSTEMSERVICEDIR=${!outputBin}/share/dbus-1/system-services"
-    cmakeFlags+=" -DKDE_INSTALL_SYSCONFDIR=${!outputBin}/etc"
-    cmakeFlags+=" -DKDE_INSTALL_CONFDIR=${!outputBin}/etc/xdg"
-    cmakeFlags+=" -DKDE_INSTALL_AUTOSTARTDIR=${!outputBin}/etc/xdg/autostart"
-    cmakeFlags+=" -DKDE_INSTALL_LOGGINGCATEGORIESDIR=${!outputLib}/share/qlogging-categories6"
-    cmakeFlags+=" -DKDE_INSTALL_SYSTEMDUNITDIR=${!outputBin}/lib/systemd"
-    cmakeFlags+=" -DKDE_INSTALL_SYSTEMDUSERUNITDIR=${!outputBin}/share/systemd/user"
+    appendToVar cmakeFlags "-DKDE_INSTALL_INCLUDEDIR=${!outputInclude}/include"
+    appendToVar cmakeFlags "-DKDE_INSTALL_LOCALSTATEDIR=/var"
+    appendToVar cmakeFlags "-DKDE_INSTALL_SHAREDSTATEDIR=/com"  # ???
+    appendToVar cmakeFlags "-DKDE_INSTALL_DATAROOTDIR=${!outputBin}/share"
+    appendToVar cmakeFlags "-DKDE_INSTALL_DATADIR=${!outputBin}/share"
+    appendToVar cmakeFlags "-DKDE_INSTALL_DOCBUNDLEDIR=${!outputBin}/share/doc/HTML"
+    appendToVar cmakeFlags "-DKDE_INSTALL_KCFGDIR=${!outputBin}/share/config.kcfg"
+    appendToVar cmakeFlags "-DKDE_INSTALL_KCONFUPDATEDIR=${!outputBin}/share/kconf_update"
+    appendToVar cmakeFlags "-DKDE_INSTALL_KAPPTEMPLATESDIR=${!outputDev}/share/kdevappwizard/templates"
+    appendToVar cmakeFlags "-DKDE_INSTALL_KFILETEMPLATESDIR=${!outputDev}/share/kdevfiletemplates/templates"
+    appendToVar cmakeFlags "-DKDE_INSTALL_KXMLGUIDIR=${!outputBin}/share/kxmlgui5"  # Yes, this needs to be 5 and not 6. Don't ask.
+    appendToVar cmakeFlags "-DKDE_INSTALL_KNOTIFYRCDIR=${!outputBin}/share/knotifications6"
+    appendToVar cmakeFlags "-DKDE_INSTALL_ICONDIR=${!outputBin}/share/icons"
+    appendToVar cmakeFlags "-DKDE_INSTALL_LOCALEDIR=${!outputLib}/share/locale"
+    appendToVar cmakeFlags "-DKDE_INSTALL_SOUNDDIR=${!outputBin}/share/sounds"
+    appendToVar cmakeFlags "-DKDE_INSTALL_TEMPLATEDIR=${!outputBin}/share/templates"
+    appendToVar cmakeFlags "-DKDE_INSTALL_WALLPAPERDIR=${!outputBin}/share/wallpapers"
+    appendToVar cmakeFlags "-DKDE_INSTALL_APPDIR=${!outputBin}/share/applications"
+    appendToVar cmakeFlags "-DKDE_INSTALL_DESKTOPDIR=${!outputBin}/share/desktop-directories"
+    appendToVar cmakeFlags "-DKDE_INSTALL_MIMEDIR=${!outputBin}/share/mime/packages"
+    appendToVar cmakeFlags "-DKDE_INSTALL_METAINFODIR=${!outputBin}/share/appdata"
+    appendToVar cmakeFlags "-DKDE_INSTALL_QTQCHDIR=${!outputLib}/share/doc/qch"
+    appendToVar cmakeFlags "-DKDE_INSTALL_QCHDIR=${!outputLib}/share/doc/qch"
+    appendToVar cmakeFlags "-DKDE_INSTALL_MANDIR=${!outputBin}/share/man"
+    appendToVar cmakeFlags "-DKDE_INSTALL_INFODIR=${!outputBin}/share/info"
+    appendToVar cmakeFlags "-DKDE_INSTALL_DBUSDIR=${!outputBin}/share/dbus-1"
+    appendToVar cmakeFlags "-DKDE_INSTALL_DBUSINTERFACEDIR=${!outputBin}/share/dbus-1/interfaces"
+    appendToVar cmakeFlags "-DKDE_INSTALL_DBUSSERVICEDIR=${!outputBin}/share/dbus-1/services"
+    appendToVar cmakeFlags "-DKDE_INSTALL_DBUSSYSTEMSERVICEDIR=${!outputBin}/share/dbus-1/system-services"
+    appendToVar cmakeFlags "-DKDE_INSTALL_SYSCONFDIR=${!outputBin}/etc"
+    appendToVar cmakeFlags "-DKDE_INSTALL_CONFDIR=${!outputBin}/etc/xdg"
+    appendToVar cmakeFlags "-DKDE_INSTALL_AUTOSTARTDIR=${!outputBin}/etc/xdg/autostart"
+    appendToVar cmakeFlags "-DKDE_INSTALL_LOGGINGCATEGORIESDIR=${!outputLib}/share/qlogging-categories6"
+    appendToVar cmakeFlags "-DKDE_INSTALL_SYSTEMDUNITDIR=${!outputBin}/lib/systemd"
+    appendToVar cmakeFlags "-DKDE_INSTALL_SYSTEMDUSERUNITDIR=${!outputBin}/share/systemd/user"
 }
 postHooks+=(ecmPostHook)
 
diff --git a/pkgs/os-specific/bsd/freebsd/pkgs/freebsdSetupHook/setup-hook.sh b/pkgs/os-specific/bsd/freebsd/pkgs/freebsdSetupHook/setup-hook.sh
index 96a3d14c80f7..ac6e9c12229a 100644
--- a/pkgs/os-specific/bsd/freebsd/pkgs/freebsdSetupHook/setup-hook.sh
+++ b/pkgs/os-specific/bsd/freebsd/pkgs/freebsdSetupHook/setup-hook.sh
@@ -1,22 +1,22 @@
 setFreeBSDSrcTop() {
-  makeFlags="SRCTOP=$BSDSRCDIR $makeFlags"
+  prependToVar makeFlags "SRCTOP=$BSDSRCDIR"
 }
 
 addFreeBSDMakeFlags() {
-  makeFlags="SBINDIR=${!outputBin}/bin $makeFlags"
-  makeFlags="LIBEXECDIR=${!outputLib}/libexec $makeFlags"
-  makeFlags="LIBDATADIR=${!outputLib}/data $makeFlags"
-  makeFlags="INCLUDEDIR=${!outputDev}/include $makeFlags"
-  makeFlags="CONFDIR=${!outputBin}/etc $makeFlags"
-  makeFlags="MANDIR=${!outputMan}/share/man/man $makeFlags"
+  prependToVar makeFlags "SBINDIR=${!outputBin}/bin"
+  prependToVar makeFlags "LIBEXECDIR=${!outputLib}/libexec"
+  prependToVar makeFlags "LIBDATADIR=${!outputLib}/data"
+  prependToVar makeFlags "INCLUDEDIR=${!outputDev}/include"
+  prependToVar makeFlags "CONFDIR=${!outputBin}/etc"
+  prependToVar makeFlags "MANDIR=${!outputMan}/share/man/man"
 
   if [ -n "$debug" ]; then
-    makeFlags="DEBUGFILEDIR=${debug}/lib/debug $makeFlags"
+    prependToVar makeFlags "DEBUGFILEDIR=${debug}/lib/debug"
   else
-    makeFlags="DEBUGFILEDIR=${out}/lib/debug $makeFlags"
+    prependToVar makeFlags "DEBUGFILEDIR=${out}/lib/debug"
   fi
 
-  echo $makeFlags
+  echoCmd 'FreeBSD makeFlags' "${makeFlags[@]}"
 }
 
 postUnpackHooks+=(setFreeBSDSrcTop)
diff --git a/pkgs/os-specific/bsd/netbsd/pkgs/compat/package.nix b/pkgs/os-specific/bsd/netbsd/pkgs/compat/package.nix
index 40113028bbf1..56db4901c6a8 100644
--- a/pkgs/os-specific/bsd/netbsd/pkgs/compat/package.nix
+++ b/pkgs/os-specific/bsd/netbsd/pkgs/compat/package.nix
@@ -74,7 +74,7 @@ mkDerivation (
         # Makefiles only invoke `$OBJCOPY -x/-X`, so cctools strip works here.
         "OBJCOPY=${cctools}/bin/strip"
       ];
-    RENAME = "-D";
+    env.RENAME = "-D";
 
     passthru.tests = {
       netbsd-install = install;
diff --git a/pkgs/os-specific/bsd/netbsd/pkgs/netbsdSetupHook/setup-hook.sh b/pkgs/os-specific/bsd/netbsd/pkgs/netbsdSetupHook/setup-hook.sh
index 8c3742a76534..d05461ad10cb 100644
--- a/pkgs/os-specific/bsd/netbsd/pkgs/netbsdSetupHook/setup-hook.sh
+++ b/pkgs/os-specific/bsd/netbsd/pkgs/netbsdSetupHook/setup-hook.sh
@@ -1,6 +1,6 @@
 addNetBSDMakeFlags() {
-  makeFlags="INCSDIR=${!outputDev}/include $makeFlags"
-  makeFlags="MANDIR=${!outputMan}/share/man $makeFlags"
+  prependToVar makeFlags "INCSDIR=${!outputDev}/include"
+  prependToVar makeFlags "MANDIR=${!outputMan}/share/man"
 }
 
 preConfigureHooks+=(addNetBSDMakeFlags)
diff --git a/pkgs/os-specific/bsd/openbsd/pkgs/openbsdSetupHook/setup-hook.sh b/pkgs/os-specific/bsd/openbsd/pkgs/openbsdSetupHook/setup-hook.sh
index c0fee276fea3..e06dbda37c40 100644
--- a/pkgs/os-specific/bsd/openbsd/pkgs/openbsdSetupHook/setup-hook.sh
+++ b/pkgs/os-specific/bsd/openbsd/pkgs/openbsdSetupHook/setup-hook.sh
@@ -1,6 +1,6 @@
 addOpenBSDMakeFlags() {
-  makeFlags="INCSDIR=${!outputDev}/include $makeFlags"
-  makeFlags="MANDIR=${!outputMan}/share/man $makeFlags"
+  prependToVar makeFlags "INCSDIR=${!outputDev}/include"
+  prependToVar makeFlags "MANDIR=${!outputMan}/share/man"
 }
 
 fixOpenBSDInstallDirs() {
diff --git a/pkgs/os-specific/bsd/setup-hook.sh b/pkgs/os-specific/bsd/setup-hook.sh
index bc8d372ca8b8..08dfdd4b14b6 100644
--- a/pkgs/os-specific/bsd/setup-hook.sh
+++ b/pkgs/os-specific/bsd/setup-hook.sh
@@ -1,3 +1,5 @@
+# shellcheck shell=bash disable=SC2154,SC2164
+
 # BSD makefiles should be able to detect this
 # but without they end up using gcc on Darwin stdenv
 addMakeFlags() {
@@ -35,38 +37,38 @@ addMakeFlags() {
   export MKUNPRIVED=yes
   export EXTERNAL_TOOLCHAIN=yes
 
-  makeFlags="MACHINE=$MACHINE $makeFlags"
-  makeFlags="MACHINE_ARCH=$MACHINE_ARCH $makeFlags"
-  makeFlags="AR=$AR $makeFlags"
-  makeFlags="CC=$CC $makeFlags"
-  makeFlags="CPP=$CPP $makeFlags"
-  makeFlags="CXX=$CXX $makeFlags"
-  makeFlags="LD=$LD $makeFlags"
-  makeFlags="STRIP=$STRIP $makeFlags"
+  prependToVar makeFlags "MACHINE=$MACHINE"
+  prependToVar makeFlags "MACHINE_ARCH=$MACHINE_ARCH"
+  prependToVar makeFlags "AR=$AR"
+  prependToVar makeFlags "CC=$CC"
+  prependToVar makeFlags "CPP=$CPP"
+  prependToVar makeFlags "CXX=$CXX"
+  prependToVar makeFlags "LD=$LD"
+  prependToVar makeFlags "STRIP=$STRIP"
 
-  makeFlags="BINDIR=${!outputBin}/bin $makeFlags"
-  makeFlags="LIBDIR=${!outputLib}/lib $makeFlags"
-  makeFlags="SHLIBDIR=${!outputLib}/lib $makeFlags"
-  makeFlags="SHAREDIR=${!outputLib}/share $makeFlags"
-  makeFlags="INFODIR=${!outputInfo}/share/info $makeFlags"
-  makeFlags="DOCDIR=${!outputDoc}/share/doc $makeFlags"
-  makeFlags="LOCALEDIR=${!outputLib}/share/locale $makeFlags"
+  prependToVar makeFlags "BINDIR=${!outputBin}/bin"
+  prependToVar makeFlags "LIBDIR=${!outputLib}/lib"
+  prependToVar makeFlags "SHLIBDIR=${!outputLib}/lib"
+  prependToVar makeFlags "SHAREDIR=${!outputLib}/share"
+  prependToVar makeFlags "INFODIR=${!outputInfo}/share/info"
+  prependToVar makeFlags "DOCDIR=${!outputDoc}/share/doc"
+  prependToVar makeFlags "LOCALEDIR=${!outputLib}/share/locale"
 
   # Parallel building. Needs the space.
-  makeFlags="-j $NIX_BUILD_CORES $makeFlags"
+  prependToVar makeFlags "-j $NIX_BUILD_CORES"
 }
 
 setBSDSourceDir() {
   sourceRoot=$PWD/$sourceRoot
   export BSDSRCDIR=$sourceRoot
   export _SRC_TOP_=$BSDSRCDIR
-  cd $sourceRoot
+  cd "$sourceRoot"
 }
 
 cdBSDPath() {
   if [ -d "$COMPONENT_PATH" ]
     then sourceRoot=$sourceRoot/$COMPONENT_PATH
-    cd $COMPONENT_PATH
+    cd "$COMPONENT_PATH"
   fi
 }
 
@@ -74,10 +76,9 @@ includesPhase() {
   if [ -z "${skipIncludesPhase:-}" ]; then
     runHook preIncludes
 
-    local flagsArray=(
-         $makeFlags ${makeFlagsArray+"${makeFlagsArray[@]}"}
-         includes
-    )
+    local flagsArray=()
+    concatTo flagsArray makeFlags makeFlagsArray
+    flagsArray+=(includes)
 
     echoCmd 'includes flags' "${flagsArray[@]}"
     make ${makefile:+-f $makefile} "${flagsArray[@]}"
@@ -89,19 +90,19 @@ includesPhase() {
 }
 
 moveUsrDir() {
-  if [ -d $prefix ]; then
+  if [ -d "$prefix" ]; then
     # Remove lingering /usr references
-    if [ -d $prefix/usr ]; then
+    if [ -d "$prefix/usr" ]; then
       # Didn't try using rsync yet because per
       # https://unix.stackexchange.com/questions/127712/merging-folders-with-mv,
       # it's not neessarily better.
-      pushd $prefix/usr
-      find . -type d -exec mkdir -p $out/\{} \;
-      find . \( -type f -o -type l \) -exec mv \{} $out/\{} \;
+      pushd "$prefix/usr"
+      find . -type d -exec mkdir -p "$out/{}" \;
+      find . \( -type f -o -type l \) -exec mv "{}" "$out/{}" \;
       popd
     fi
 
-    find $prefix -type d -empty -delete
+    find "$prefix" -type d -empty -delete
   fi
 }