diff --git a/system/Makefile b/system/Makefile
index 82ad640..495b679 100644
--- a/system/Makefile
+++ b/system/Makefile
@@ -79,10 +79,14 @@ synth_ecp5.json: ${SOURCES} ${TOP_LEVEL_SOURCE} fpga_config/${FPGA_BOARD}/fpga_t
 	${QUIET_YOSYS}
 	${Q} yosys -q -D BUILTIN_RAM=2048 -D NOT_FULL -p 'read -sv '"${SOURCES} ${TOP_LEVEL_SOURCE} fpga_config/${FPGA_BOARD}/fpga_top.v ${EXTRA_SYNTHESIS_SOURCES} ; synth_ecp5 -json $@ -abc9 -top fpga_top"
 
+RANDOM :::= $(shell seq 1 200|sort -R|head -n1)
+
 synth_ecp5_out.config:synth_ecp5.json
 	${QUIET_NEXTPNR}
-	${Q} nextpnr-ecp5 --Werror -q --json $< --textcfg $@ ${NEXTPNR_ECP5_DEV} --package ${ECP5_PACKAGE} --lpf fpga_config/${FPGA_BOARD}/pin_constraint.pcf --report=synth_pnr_report.json
+	${Q}printf '\e[1;30mNotice: nextpnr rng seed is : %s\e[0m\n' "${RANDOM}"
+	${Q} nextpnr-ecp5 --seed ${RANDOM} --Werror -q --json $< --textcfg $@.1 ${NEXTPNR_ECP5_DEV} --package ${ECP5_PACKAGE} --lpf fpga_config/${FPGA_BOARD}/pin_constraint.pcf --report=synth_pnr_report.json
 	${Q}../tools/parse_nextpnr_stats.sh --brief synth_pnr_report.json
+	${Q}mv "$@.1" "$@"
 
 synth_ecp5.bit:synth_ecp5_out.config
 	${QUIET_ECPPACK}
@@ -99,6 +103,9 @@ upload_orangecrab:synth_ecp5.dfu
 	${QUIET_DFU_UTIL}
 	${Q}stdbuf -o0 dfu-util --download "$<" |stdbuf -o0 tr '\n' '\a' | stdbuf -o0 tr '\r' '\n' | grep Download --line-buffered | stdbuf -o0 tr '\n' '\r' |stdbuf -o0 tr '\a' '\n'
 
+nextpnr-gui: synth_ecp5.json
+	${Q} nextpnr-ecp5 --json $< ${NEXTPNR_ECP5_DEV} --package ${ECP5_PACKAGE} --lpf fpga_config/${FPGA_BOARD}/pin_constraint.pcf --gui
+
 upload: upload_orangecrab
 
 .PHONY: clean