diff --git a/.vscode/extensions.json b/.vscode/extensions.json
index 51e530ec51..c5410cb309 100644
--- a/.vscode/extensions.json
+++ b/.vscode/extensions.json
@@ -2,6 +2,7 @@
     "recommendations": [
         "marus25.cortex-debug",
         "Gruntfuggly.todo-tree",
-        "ms-vscode.cpptools"
+		"ms-vscode.cpptools",
+		"vadimcn.vscode-lldb"
     ]
 }
\ No newline at end of file
diff --git a/.vscode/launch.json b/.vscode/launch.json
index 375a6017cc..a29299bfb8 100644
--- a/.vscode/launch.json
+++ b/.vscode/launch.json
@@ -5,7 +5,7 @@
 	"version": "0.2.0",
 	"configurations": [
 		{
-			"name": "Debug Unit Tests",
+			"name": "Debug Unit Tests (gdb)",
 			"type": "cppdbg",
 			"request": "launch",
 			"program": "${workspaceFolder}/unit_tests/build/rusefi_test",
@@ -24,6 +24,14 @@
 				}
 			]
 		},
+		{
+			"name": "Debug Unit Tests (lldb)",
+			"type": "lldb",
+			"request": "launch",
+			"program": "${workspaceFolder}/unit_tests/build/rusefi_test",
+			"args": [],
+			"cwd": "${workspaceFolder}/unit_tests/build/",
+		},
 		{
             "name": "Debug F40x",
             "type": "cortex-debug",
diff --git a/unit_tests/Makefile b/unit_tests/Makefile
index d1da8c3cfd..b2d250f716 100644
--- a/unit_tests/Makefile
+++ b/unit_tests/Makefile
@@ -18,16 +18,12 @@ include $(PROJECT_DIR)/rusefi_rules.mk
 
 # Compiler options here.
 ifeq ($(USE_OPT),)
-# As of Jan 2016 we are producing 64 bit unit tests on Windows which needs 64 bit GDB
-# Previouslyt we had to download 32 bit version of GDB maybe from http://www.equation.com/servlet/equation.cmd?fa=gdb
-#
 # -O2 is needed for mingw, without it there is a linking issue to isnanf?!?!
   #USE_OPT = $(RFLAGS) -O2 -fgnu89-inline -ggdb -fomit-frame-pointer -falign-functions=16 -std=gnu99 -Werror-implicit-function-declaration -Werror -Wno-error=pointer-sign -Wno-error=unused-function -Wno-error=unused-variable -Wno-error=sign-compare -Wno-error=unused-parameter -Wno-error=missing-field-initializers
   USE_OPT = -c -Wall -O0 -ggdb -g3
   USE_OPT += -fprofile-arcs -ftest-coverage
   USE_OPT += -Werror=missing-field-initializers
   USE_OPT += -Wno-unused-parameter -Wno-unused-function
-  USE_OPT += -fsingle-precision-constant
 endif
 
 
@@ -297,7 +293,7 @@ ULIBDIR =
 
 # List all user libraries here
 ULIBS = -lm
-ULIBS += -lgcov --coverage
+ULIBS += --coverage
 
 #
 # End of user defines
diff --git a/unit_tests/rules.mk b/unit_tests/rules.mk
index 5e93b3e311..8d775c6ce0 100644
--- a/unit_tests/rules.mk
+++ b/unit_tests/rules.mk
@@ -54,16 +54,33 @@ ADEFS 	  = $(DADEFS) $(UADEFS)
 LIBS      = $(DLIBS) $(ULIBS)
 
 # Various settings
-#MCFLAGS   = -mcpu=$(MCU)
-ODFLAGS	  = -x --syms
-ASFLAGS   = $(MCFLAGS) -Wa,-amhls=$(LSTDIR)/$(notdir $(<:.s=.lst)) $(ADEFS)
-ASXFLAGS  = $(MCFLAGS) -Wa,-amhls=$(LSTDIR)/$(notdir $(<:.S=.lst)) $(ADEFS)
-CFLAGS    = $(MCFLAGS) $(OPT) $(COPT) $(CWARN) -Wa,-alms=$(LSTDIR)/$(notdir $(<:.c=.lst)) $(DEFS)
-CPPFLAGS  = $(MCFLAGS) $(OPT) $(CPPOPT) $(CPPWARN) -Wa,-alms=$(LSTDIR)/$(notdir $(<:.cpp=.lst)) $(DEFS)
-ifeq ($(USE_LINK_GC),yes)
-  LDFLAGS = $(MCFLAGS) -Wl,-Map=$(BUILDDIR)/$(PROJECT).map,--cref,--no-warn-mismatch,--gc-sections $(LLIBDIR)
+IS_MAC = no
+ifneq ($(OS),Windows_NT)
+	UNAME_S := $(shell uname -s)
+    ifeq ($(UNAME_S),Darwin)
+        IS_MAC = yes
+    endif
+endif
+
+ifeq ($(IS_MAC),yes)
+	ODFLAGS	  = -x --syms
+	ASFLAGS   = $(MCFLAGS) -Wa,-amhls=$(LSTDIR)/$(notdir $(<:.s=.lst)) $(ADEFS)
+	ASXFLAGS  = $(MCFLAGS) -Wa,-amhls=$(LSTDIR)/$(notdir $(<:.S=.lst)) $(ADEFS)
+	CFLAGS    = $(MCFLAGS) $(OPT) $(COPT)   $(CWARN)   $(DEFS)
+	CPPFLAGS  = $(MCFLAGS) $(OPT) $(CPPOPT) $(CPPWARN) $(DEFS)
+	LDFLAGS = $(MCFLAGS) $(LLIBDIR)
 else
-  LDFLAGS = $(MCFLAGS) -Wl,-Map=$(BUILDDIR)/$(PROJECT).map,--cref,--no-warn-mismatch $(LLIBDIR)
+	# not mac
+	ODFLAGS	  = -x --syms
+	ASFLAGS   = $(MCFLAGS) -Wa,-amhls=$(LSTDIR)/$(notdir $(<:.s=.lst)) $(ADEFS)
+	ASXFLAGS  = $(MCFLAGS) -Wa,-amhls=$(LSTDIR)/$(notdir $(<:.S=.lst)) $(ADEFS)
+	CFLAGS    = $(MCFLAGS) $(OPT) $(COPT) $(CWARN) -Wa,-alms=$(LSTDIR)/$(notdir $(<:.c=.lst)) $(DEFS)
+	CPPFLAGS  = $(MCFLAGS) $(OPT) $(CPPOPT) $(CPPWARN) -Wa,-alms=$(LSTDIR)/$(notdir $(<:.cpp=.lst)) $(DEFS)
+	ifeq ($(USE_LINK_GC),yes)
+	  LDFLAGS = $(MCFLAGS) -Wl,-Map=$(BUILDDIR)/$(PROJECT).map,--cref,--no-warn-mismatch,--gc-sections $(LLIBDIR)
+	else
+	  LDFLAGS = $(MCFLAGS) -Wl,-Map=$(BUILDDIR)/$(PROJECT).map,--cref,--no-warn-mismatch $(LLIBDIR)
+	endif
 endif
 
 # Generate dependency information