diff --git a/Makefile b/Makefile
index 1f3a537d4..82d36fea2 100644
--- a/Makefile
+++ b/Makefile
@@ -15,10 +15,9 @@
 #
 # Target naming scheme
 #
-#   Main targets: {dev,debug,release,debug_release}.{linux,stm32f{4}}[.{check,flash}]
+#   Main targets: {debug,release,debug_release}.{linux,stm32f{4}}[.{check,flash}]
 #
 #    Target mode part (before dot):
-#       dev:           - JERRY_NDEBUG; - optimizations; + debug symbols; - -Werror  | local development build
 #       debug:         - JERRY_NDEBUG; - optimizations; + debug symbols; + -Werror  | debug build
 #       debug_release: - JERRY_NDEBUG; + optimizations; + debug symbols; + -Werror  | checked release build
 #       release:       + JERRY_NDEBUG; + optimizations; - debug symbols; + -Werror  | release build
@@ -35,7 +34,7 @@
 #   Unit test target: unittests
 #
 
-export TARGET_MODES = dev debug debug_release release
+export TARGET_MODES = debug debug_release release
 export TARGET_PC_SYSTEMS = linux
 export TARGET_MCU_SYSTEMS = $(addprefix stm32f,4) # now only stm32f4 is supported, to add, for example, to stm32f3, change to $(addprefix stm32f,3 4)
 export TARGET_SYSTEMS = $(TARGET_PC_SYSTEMS) $(TARGET_MCU_SYSTEMS)
diff --git a/Makefile.mak b/Makefile.mak
index ec77a95d2..fdc510b62 100644
--- a/Makefile.mak
+++ b/Makefile.mak
@@ -59,13 +59,6 @@ else
  OPTION_OPTIMIZE = disable
 endif
 
-# -Werror
-ifeq ($(TARGET_MODE),dev)
- OPTION_WERROR = disable
-else
- OPTION_WERROR = enable
-endif
-
 # Is MCU target?
 ifeq ($(filter-out $(TARGET_MCU_SYSTEMS),$(TARGET_SYSTEM)),)
 	OPTION_MCU = enable
@@ -149,7 +142,7 @@ endif
 # Jerry part sources, headers, includes, cflags, ldflags
 #
 
-CFLAGS_JERRY = $(CFLAGS_WARNINGS)
+CFLAGS_JERRY = $(CFLAGS_WARNINGS) $(CFLAGS_WERROR)
 DEFINES_JERRY = -DMEM_HEAP_CHUNK_SIZE=256 -DMEM_HEAP_AREA_SIZE=32768 -DMEM_STATS
 
 # FIXME:
@@ -181,10 +174,6 @@ ifeq ($(OPTION_NDEBUG),enable)
  DEFINES_JERRY += -DJERRY_NDEBUG
 endif
 
-ifeq ($(OPTION_WERROR),enable)
- CFLAGS_JERRY += $(CFLAGS_WERROR)
-endif
-
 ifeq ($(OPTION_MCU),disable)
  DEFINES_JERRY += -D__HOST -DJERRY_SOURCE_BUFFER_SIZE=1048576
 else