diff --git a/etc/kaleidoscope-builder.conf b/etc/kaleidoscope-builder.conf
index ac55dac8..aa5865b3 100644
--- a/etc/kaleidoscope-builder.conf
+++ b/etc/kaleidoscope-builder.conf
@@ -31,74 +31,73 @@ uname_S=$(uname -s 2>/dev/null || echo not)
 uname_O=$(uname -o 2>/dev/null || echo not)
 
 find_device_port() {
+	if [ -n "${DEVICE_PORT}" ]; then
+		echo "DEVICE_PORT=\"${DEVICE_PORT}\" predefined."
+		return
+	fi
+
 	find_device_vid_pid
-	DEVICE_PORT_PROBER="${KALEIDOSCOPE_BIN_DIR}/find-device-port-linux-udev"
-	if [[ "${DEVICE_PORT}" = "" ]]; then
+	if [ "${uname_S}" = "Darwin" ]; then
+		DEVICE_PORT_PROBER="${KALEIDOSCOPE_BIN_DIR}/find-device-port-macos"
 		DEVICE_PORT="$(perl ${DEVICE_PORT_PROBER} ${VID} ${SKETCH_PID})"
+	elif [ "${uname_O}" = "Cygwin" ]; then
+		DEVICE_PORT_PROBER="${KALEIDOSCOPE_BIN_DIR}/find-device-port-windows.ps1"
+		DEVICE_PORT="$(powershell -noprofile -executionpolicy bypass ${DEVICE_PORT_PROBER} ${VID} ${SKETCH_PID} -Format Cygwin)"
+		DEVICE_COM_PORT="$(powershell -noprofile -executionpolicy bypass ${DEVICE_PORT_PROBER} ${VID} ${SKETCH_PID} -Format COM)"
+	elif [ "${uname_S}" = "FreeBSD" ]; then
+		DEVICE_PORT_PROBER="${KALEIDOSCOPE_BIN_DIR}/find-device-port-freebsd"
+		DEVICE_PORT="$(perl ${DEVICE_PORT_PROBER})"
 	else
-		echo "DEVICE_PORT=\"${DEVICE_PORT}\" predefined."
+		DEVICE_PORT_PROBER="${KALEIDOSCOPE_BIN_DIR}/find-device-port-linux-udev"
+		DEVICE_PORT="$(perl ${DEVICE_PORT_PROBER} ${VID} ${SKETCH_PID})"
 	fi
 }
 
 reset_device_cmd() {
 	if [ -z ${NO_RESET} ]; then
-		stty -F ${DEVICE_PORT} 1200 hupcl
+		if [ "${uname_S}" = "Darwin" ]; then
+			/bin/stty -f ${DEVICE_PORT} 1200
+		elif [ "${uname_S}" = "FreeBSD" ]; then
+			/bin/stty -f ${DEVICE_PORT} 1200
+
+		elif [ "${uname_O}" = "Cygwin" ]; then
+			cmd /c mode ${DEVICE_COM_PORT} baud=1200
+		else
+			stty -F ${DEVICE_PORT} 1200 hupcl
+		fi
 	fi
 }
 
 find_bootloader_ports() {
-	find_device_vid_pid
-	: "${BOOTLOADER_VID:=${VID}}"
-	DEVICE_PORT_PROBER="${KALEIDOSCOPE_BIN_DIR}/find-device-port-linux-udev"
-	if [[ "${DEVICE_PORT_BOOTLOADER}" = "" ]]; then
-		DEVICE_PORT_BOOTLOADER="$(perl ${DEVICE_PORT_PROBER} ${BOOTLOADER_VID} ${BOOTLOADER_PID})"
-	else
+	if [ -n "${DEVICE_PORT_BOOTLOADER}" ]; then
 		echo "DEVICE_PORT_BOOTLOADER=\"${DEVICE_PORT_BOOTLOADER}\" predefined."
+		return
 	fi
-}
-
-if [ "${uname_S}" = "Darwin" ]; then
 
-	find_device_port() {
-		DEVICE_PORT_PROBER="${KALEIDOSCOPE_BIN_DIR}/find-device-port-macos"
-		DEVICE_PORT="$(perl ${DEVICE_PORT_PROBER} ${VID} ${SKETCH_PID})"
-	}
-
-	reset_device_cmd() {
-		/bin/stty -f ${DEVICE_PORT} 1200
-	}
-
-	find_bootloader_ports() {
-		find_device_vid_pid
-		: "${BOOTLOADER_VID:=${VID}}"
+	find_device_vid_pid
+	: "${BOOTLOADER_VID:=${VID}}"
+	if [ "${uname_S}" = "Darwin" ]; then
 		DEVICE_PORT_PROBER="${KALEIDOSCOPE_BIN_DIR}/find-device-port-macos"
-		if [[ "${DEVICE_PORT_BOOTLOADER}" = "" ]]; then
-			DEVICE_PORT_BOOTLOADER="$(perl ${DEVICE_PORT_PROBER} ${BOOTLOADER_VID} ${BOOTLOADER_PID})"
-		else
-			echo "DEVICE_PORT_BOOTLOADER=\"${DEVICE_PORT_BOOTLOADER}\" predefined."
-		fi
-	}
-
-elif [ "${uname_S}" = "FreeBSD" ]; then
+		DEVICE_PORT_BOOTLOADER="$(perl ${DEVICE_PORT_PROBER} ${BOOTLOADER_VID} ${BOOTLOADER_PID})"
+	elif [ "${uname_O}" = "Cygwin" ]; then
+		DEVICE_PORT_PROBER="${KALEIDOSCOPE_BIN_DIR}/find-device-port-windows.ps1"
+		DEVICE_PORT_BOOTLOADER="$(powershell -noprofile -executionpolicy bypass ${DEVICE_PORT_PROBER} ${BOOTLOADER_VID} ${BOOTLOADER_PID} -Format COM)"
+	elif [ "${uname_S}" = "FreeBSD" ]; then
+		DEVICE_PORT_PROBER="${KALEIDOSCPE_BIN_DIR}/find-device-port-freebsd"
+		DEVICE_PORT_BOOTLOADER="$(perl ${DEVICE_PORT_PROBER})"
 
-	find_device_port() {
-		DEVICE_PORT_PROBER="${KALEIDOSCOPE_BIN_DIR}/find-device-port-freebsd"
-		DEVICE_PORT="$(perl ${DEVICE_PORT_PROBER})"
-	}
+	else
 
-	reset_device_cmd() {
-		/bin/stty -f ${DEVICE_PORT} 1200
-	}
+		DEVICE_PORT_PROBER="${KALEIDOSCOPE_BIN_DIR}/find-device-port-linux-udev"
+		DEVICE_PORT_BOOTLOADER="$(perl ${DEVICE_PORT_PROBER} ${BOOTLOADER_VID} ${BOOTLOADER_PID})"
+	fi
+}
 
+if [ "${uname_S}" = "FreeBSD" ]; then
 	: "${AVR_SIZE:=/usr/local/bin/avr-size}"
 	: "${AVR_NM:=/usr/local/bin/avr-nm}"
 	: "${AVR_OBJDUMP:=/usr/local/bin/avr-objdump}"
 
-	find_bootloader_ports() {
-		DEVICE_PORT_PROBER="${KALEIDOSCPE_BIN_DIR}/find-device-port-freebsd"
-		DEVICE_PORT_BOOTLOADER="$(perl ${DEVICE_PORT_PROBER})"
-	}
-
 	if [ "${ARCH}" = "virtual" ]; then
 		: "${COMPILER_PATH:=/usr/local/bin/}"
 	fi
@@ -125,22 +124,4 @@ elif [ "${uname_O}" = "Cygwin" ]; then
 
 	TMPDIR="$(realpath --relative-to=./ ${TMPDIR})"
 
-	find_device_port() {
-		find_device_vid_pid
-		DEVICE_PORT_PROBER="${KALEIDOSCOPE_BIN_DIR}/find-device-port-windows.ps1"
-		DEVICE_PORT="$(powershell -noprofile -executionpolicy bypass ${DEVICE_PORT_PROBER} ${VID} ${SKETCH_PID} -Format Cygwin)"
-		DEVICE_COM_PORT="$(powershell -noprofile -executionpolicy bypass ${DEVICE_PORT_PROBER} ${VID} ${SKETCH_PID} -Format COM)"
-	}
-
-	reset_device_cmd() {
-		cmd /c mode ${DEVICE_COM_PORT} baud=1200
-	}
-
-	find_bootloader_ports() {
-		find_device_vid_pid
-		: "${BOOTLOADER_VID:=${VID}}"
-		DEVICE_PORT_PROBER="${KALEIDOSCOPE_BIN_DIR}/find-device-port-windows.ps1"
-		DEVICE_PORT_BOOTLOADER="$(powershell -noprofile -executionpolicy bypass ${DEVICE_PORT_PROBER} ${BOOTLOADER_VID} ${BOOTLOADER_PID} -Format COM)"
-	}
-
 fi