diff --git a/bin/kaleidoscope-builder b/bin/kaleidoscope-builder
index 0f2405ae..b0111260 100755
--- a/bin/kaleidoscope-builder
+++ b/bin/kaleidoscope-builder
@@ -61,31 +61,31 @@ enable_ccache () {
       if ! [ -d "$CCACHE_WRAPPER_PATH" ]; then
          mkdir -p "$CCACHE_WRAPPER_PATH"
       fi
-      
+
       if ! [ -h "${CCACHE_WRAPPER_PATH}/${COMPILER_PREFIX}${C_COMPILER_BASENAME}" ]; then
          ln -s "$(command -v ccache)" "${CCACHE_WRAPPER_PATH}/${COMPILER_PREFIX}${C_COMPILER_BASENAME}"
       fi
-      
+
       if ! [ -h "${CCACHE_WRAPPER_PATH}/${COMPILER_PREFIX}${CXX_COMPILER_BASENAME}" ]; then
          ln -s "$(command -v ccache)" "${CCACHE_WRAPPER_PATH}/${COMPILER_PREFIX}${CXX_COMPILER_BASENAME}"
       fi
-      
+
       if ! [ -h "${CCACHE_WRAPPER_PATH}/${COMPILER_PREFIX}nm" ]; then
          ln -s "${AVR_NM}" "${CCACHE_WRAPPER_PATH}/${COMPILER_PREFIX}nm"
       fi
-      
+
       if ! [ -h "${CCACHE_WRAPPER_PATH}/${COMPILER_PREFIX}objcopy" ]; then
          ln -s "${AVR_OBJCOPY}" "${CCACHE_WRAPPER_PATH}/${COMPILER_PREFIX}objcopy"
       fi
-      
+
       if ! [ -h "${CCACHE_WRAPPER_PATH}/${COMPILER_PREFIX}ar" ]; then
          ln -s "${AVR_AR}" "${CCACHE_WRAPPER_PATH}/${COMPILER_PREFIX}ar"
       fi
-      
+
       if ! [ -h "${CCACHE_WRAPPER_PATH}/${COMPILER_PREFIX}size" ]; then
          ln -s "${AVR_SIZE}" "${CCACHE_WRAPPER_PATH}/${COMPILER_PREFIX}size"
       fi
-    
+
       export CCACHE_PATH=${COMPILER_PATH}/
       CCACHE_ENABLE="-prefs compiler.path=${CCACHE_WRAPPER_PATH}/"
     fi
@@ -163,16 +163,16 @@ prompt_before_flashing () {
 flash () {
     maybe_build "$@"
 
-    # Check to see if we can see a keyboard bootloader port. 
+    # Check to see if we can see a keyboard bootloader port.
     # If we -can-, then we should skip over the "reset to bootloader" thing
     find_bootloader_ports
     if [ -z "${DEVICE_PORT_BOOTLOADER}" ]; then
         prompt_before_flashing
-    
+
         # This is defined in the (optional) user config.
         # shellcheck disable=SC2154
         ${preFlash_HOOKS}
-  
+
 	# If we're -not- doing a manual reset, then try to do it automatically
         if [ -z "${MANUAL_RESET}" ]; then
             reset_device
@@ -195,7 +195,7 @@ flash () {
 wait_for_bootloader_port() {
     declare -i tries
     tries=15
-    
+
     while [ "$tries" -gt 0 ] && [ -z "${DEVICE_PORT_BOOTLOADER}" ]; do
         sleep 1
         printf "."
@@ -204,12 +204,12 @@ wait_for_bootloader_port() {
         # shellcheck disable=SC2004
         tries=$(($tries-1))
     done
-    
+
     if [ "$tries" -gt 0 ]; then
         echo "Found."
-    else 
+    else
         echo "Timed out."
-    fi 
+    fi
 }
 
 check_bootloader_port () {
@@ -227,11 +227,11 @@ check_bootloader_port_and_flash () {
     if ! check_bootloader_port; then
         return 1
     fi
- 
+
     echo "Flashing your keyboard:"
 
     # If the flash fails, try a second time
-    if ! flash_over_usb; then 
+    if ! flash_over_usb; then
         sleep 2
         if  ! flash_over_usb; then
             if [ "${ARDUINO_VERBOSE}" != "-verbose" ]; then
@@ -341,7 +341,7 @@ compile () {
     enable_ccache
 
     install -d "${OUTPUT_PATH}"
-    
+
     SKETCH_DIR="$(find_sketch)"
 
     echo "Building ${SKETCH_DIR}/${SKETCH} ${LIB_VERSION} into ${OUTPUT_PATH}"
@@ -362,7 +362,7 @@ compile () {
         # We want literal backslashes here, not arrays.
 	      ARDUINO_PACKAGES="-hardware \"${ARDUINO_PACKAGE_PATH}\""
     fi
-    
+
     SAVED_BOARD="${BOARD}"
     SAVED_FQBN="${FQBN}"
     if [ -e "${SKETCH_DIR}/.kaleidoscope-builder.conf" ]; then
@@ -379,6 +379,10 @@ compile () {
         fi
     fi
 
+    _CMD_CXX="${COMPILER_PREFIX}${CXX_COMPILER_BASENAME}${COMPILER_SUFFIX}"
+    _CMD_CC="${COMPILER_PREFIX}${C_COMPILER_BASENAME}${COMPILER_SUFFIX}"
+    _CMD_AR="${COMPILER_PREFIX}${AR_BASENAME}${COMPILER_SUFFIX}"
+
     # SC2091: We do not care if quotes or backslashes are not respected.
     # SC2086: We want word splitting.
     # shellcheck disable=SC2086,SC2090
@@ -401,8 +405,9 @@ compile () {
 	      -built-in-libraries "${ARDUINO_PATH}/libraries" \
 	      -prefs "compiler.cpp.extra_flags=${ARDUINO_CFLAGS} ${LOCAL_CFLAGS}" \
 	      -prefs "compiler.path=${COMPILER_PATH}" \
-	      -prefs "compiler.c.cmd=${COMPILER_PREFIX}${C_COMPILER_BASENAME}" \
-	      -prefs "compiler.cpp.cmd=${COMPILER_PREFIX}${CXX_COMPILER_BASENAME}" \
+	      -prefs "compiler.c.cmd=${_CMD_CC}" \
+	      -prefs "compiler.cpp.cmd=${_CMD_CXX}" \
+        -prefs "compiler.ar.cmd=${_CMD_AR}" \
 	      $CCACHE_ENABLE \
 	      -warnings all \
         ${ARDUINO_VERBOSE} \
@@ -605,7 +610,7 @@ usage () {
 
 		  build-all
 		    Build all Sketches we can find.
-		    
+
         run-simulator-tests
           Builds and runs all simulator tests.
 		EOF
diff --git a/etc/kaleidoscope-builder.conf b/etc/kaleidoscope-builder.conf
index 01a2e77e..72cedfa3 100644
--- a/etc/kaleidoscope-builder.conf
+++ b/etc/kaleidoscope-builder.conf
@@ -151,6 +151,12 @@ if [ "${uname_S}" = "Darwin" ]; then
         fi
     }
 
+    if [ "${ARCH}" = "virtual" ]; then
+        COMPILER_PREFIX="x86_64-apple-darwin19-"
+        COMPILER_SUFFIX="-10"
+        AR_BASENAME="gcc-ar"
+    fi
+
 elif [ "${uname_S}" = "FreeBSD" ]; then
 
     find_device_port() {
@@ -169,6 +175,7 @@ elif [ "${uname_S}" = "FreeBSD" ]; then
     AVR_OBJDUMP="${AVR_OBJDUMP:-/usr/local/bin/avr-objdump}"
     AVRDUDE="${AVRDUDE:-/usr/local/bin/avrdude}"
     AVRDUDE_CONF="${AVRDUDE_CONF:-/usr/local/etc/avrdude.conf}"
+    ARDUINO_BUILDER="${ARDUINO_BUILDER:-/usr/local/bin/arduino-builder}"
 
     find_bootloader_ports() {
 	DIR=$(dirname "$0")
@@ -176,6 +183,10 @@ elif [ "${uname_S}" = "FreeBSD" ]; then
 	DEVICE_PORT_BOOTLOADER="$(perl ${DEVICE_PORT_PROBER})"
     }
 
+    if [ "${ARCH}" = "virtual" ]; then
+        COMPILER_PATH="${COMPILER_PATH:-/usr/local/bin/}"
+    fi
+
 elif [ "${uname_O}" = "Cygwin" ]; then
     # The Windows arduino-builder.exe doesn't understand being told to exec against Cygwin symlinks
     CCACHE_NOT_SUPPORTED=1
@@ -249,8 +260,12 @@ ARDUINO_IDE_VERSION="10607"
 # Allow the compiler path to be empty for virtual builds
 COMPILER_PATH="${COMPILER_PATH-${ARDUINO_TOOLS_PATH}/avr/bin/}"
 
+COMPILER_SUFFIX=""
+
 C_COMPILER_BASENAME=$(basename ${CC:-gcc})
 CXX_COMPILER_BASENAME=$(basename ${CXX:-g++})
+AR_BASENAME=$(basename ${AR:-ar})
+OBJCOPY_BASENAME=$(basename ${OBJCOPY:-objcopy})
 
 # Allow the compiler prefix to be empty for virtual builds
 COMPILER_PREFIX="${COMPILER_PREFIX-avr-}"