diff --git a/SConscript b/SConscript.firmware
similarity index 96%
rename from SConscript
rename to SConscript.firmware
index 0d2844c71..c3792b4b9 100644
--- a/SConscript
+++ b/SConscript.firmware
@@ -455,7 +455,11 @@ SOURCE_PY = [
     'src/trezor/workflow.py',
 ]
 
-env = Environment(
+env = Environment()
+
+env.Tool('micropython')
+
+env.Replace(
     SED='sed',
     AS='arm-none-eabi-as',
     AR='arm-none-eabi-ar',
@@ -463,7 +467,9 @@ env = Environment(
     LINK='arm-none-eabi-ld',
     SIZE='arm-none-eabi-size',
     STRIP='arm-none-eabi-strip',
-    OBJCOPY='arm-none-eabi-objcopy',
+    OBJCOPY='arm-none-eabi-objcopy', )
+
+env.Replace(
     CCFLAGS='-Os '
     '-g3 '
     '-nostdlib '
@@ -492,7 +498,9 @@ env = Environment(
         'STM32F405xx',
         'TREZOR_STM32',
         'MCU_SERIES_F4',
-    ] + CPPDEFINES_MOD,
+    ] + CPPDEFINES_MOD, )
+
+env.Replace(
     PYTHON='python',
     PYTHONPATH='vendor/micropython/py',
     MAKEQSTRDEFS='$PYTHON vendor/micropython/py/makeqstrdefs.py',
@@ -500,9 +508,7 @@ env = Environment(
     MAKEVERSIONHDR='$PYTHON vendor/micropython/py/makeversionhdr.py',
     MPY_CROSS='vendor/micropython/mpy-cross/mpy-cross',
     MPY_TOOL='$PYTHON vendor/micropython/tools/mpy-tool.py',
-    MAKE_FROZEN='$PYTHON vendor/micropython/tools/make-frozen.py')
-
-env.Tool('micropython')
+    MAKE_FROZEN='$PYTHON vendor/micropython/tools/make-frozen.py', )
 
 #
 # Micropython version
@@ -520,16 +526,14 @@ hdr_version = env.Command(
 qstr_micropython = 'vendor/micropython/py/qstrdefs.h'
 
 qstr_collected = env.CollectQstr(
-    target='genhdr/qstrdefs.collected.h',
-    source=SOURCE_QSTR)
+    target='genhdr/qstrdefs.collected.h', source=SOURCE_QSTR)
 
 qstr_preprocessed = env.PreprocessQstr(
     target='genhdr/qstrdefs.preprocessed.h',
     source=[qstr_micropython, qstr_collected])
 
 qstr_generated = env.GenerateQstrDefs(
-    target='genhdr/qstrdefs.generated.h',
-    source=qstr_preprocessed)
+    target='genhdr/qstrdefs.generated.h', source=qstr_preprocessed)
 
 env.Ignore(qstr_collected, qstr_generated)
 
@@ -540,9 +544,7 @@ env.Ignore(qstr_collected, qstr_generated)
 source_mpy = env.FrozenModule(source=SOURCE_PY)
 
 source_mpyc = env.FrozenCFile(
-    target='frozen_mpy.c',
-    source=source_mpy,
-    qstr_header=qstr_preprocessed)
+    target='frozen_mpy.c', source=source_mpy, qstr_header=qstr_preprocessed)
 
 env.Depends(source_mpyc, qstr_generated)
 
@@ -550,25 +552,25 @@ env.Depends(source_mpyc, qstr_generated)
 # Program objects
 #
 
-obj_firmware = []
-obj_firmware += env.Object(source=SOURCE_MOD)
-obj_firmware += env.Object(source=SOURCE_FIRMWARE)
-obj_firmware += env.Object(source=SOURCE_MICROPYTHON)
-obj_firmware += env.Object(source=SOURCE_STMHAL)
-obj_firmware += env.Object(source=SOURCE_TREZORHAL)
-obj_firmware += env.Object(source=source_mpyc)
+obj_program = []
+obj_program += env.Object(source=SOURCE_MOD)
+obj_program += env.Object(source=SOURCE_FIRMWARE)
+obj_program += env.Object(source=SOURCE_MICROPYTHON)
+obj_program += env.Object(source=SOURCE_STMHAL)
+obj_program += env.Object(source=SOURCE_TREZORHAL)
+obj_program += env.Object(source=source_mpyc)
 
-env.Depends(obj_firmware, qstr_generated)
+env.Depends(obj_program, qstr_generated)
 
-env.Command(
+program_elf = env.Command(
     target='firmware.elf',
-    source=obj_firmware,
+    source=obj_program,
     action=
     '$LINK -o $TARGET $LINKFLAGS $SOURCES `$CC $CFLAGS $CCFLAGS $_CCCOMCOM -print-libgcc-file-name`',
 )
 
-env.Command(
+program_bin = env.Command(
     target='firmware.bin',
-    source='firmware.elf',
+    source=program_elf,
     action='$OBJCOPY -O binary -j .header -j .flash -j .data $SOURCE $TARGET',
 )
diff --git a/SConscript.unix b/SConscript.unix
new file mode 100644
index 000000000..aa3a4e903
--- /dev/null
+++ b/SConscript.unix
@@ -0,0 +1,326 @@
+# pylint: disable=E0602
+
+CCFLAGS_MOD = ''
+CPPPATH_MOD = []
+CPPDEFINES_MOD = []
+SOURCE_MOD = []
+LIBS_MOD = []
+
+# modtrezorconfig
+SOURCE_MOD += [
+    'embed/extmod/modtrezorconfig/modtrezorconfig.c',
+    'embed/extmod/modtrezorconfig/norcow.c',
+]
+
+# modtrezorcrypto
+CCFLAGS_MOD += '-Wno-sequence-point '
+CPPPATH_MOD += [
+    'embed/extmod/modtrezorcrypto/trezor-crypto',
+    'embed/extmod/modtrezorcrypto/trezor-crypto/aes',
+    'embed/extmod/modtrezorcrypto/trezor-crypto/ed25519-donna',
+]
+CPPDEFINES_MOD += [
+    'AES_128',
+    'AES_192',
+    'USE_KECCAK',
+]
+SOURCE_MOD += [
+    'embed/extmod/modtrezorcrypto/modtrezorcrypto.c',
+    'embed/extmod/modtrezorcrypto/rand.c',
+    'embed/extmod/modtrezorcrypto/ssss.c',
+    'embed/extmod/modtrezorcrypto/trezor-crypto/address.c',
+    'embed/extmod/modtrezorcrypto/trezor-crypto/aes/aescrypt.c',
+    'embed/extmod/modtrezorcrypto/trezor-crypto/aes/aeskey.c',
+    'embed/extmod/modtrezorcrypto/trezor-crypto/aes/aes_modes.c',
+    'embed/extmod/modtrezorcrypto/trezor-crypto/aes/aestab.c',
+    'embed/extmod/modtrezorcrypto/trezor-crypto/base58.c',
+    'embed/extmod/modtrezorcrypto/trezor-crypto/bignum.c',
+    'embed/extmod/modtrezorcrypto/trezor-crypto/bip32.c',
+    'embed/extmod/modtrezorcrypto/trezor-crypto/bip39.c',
+    'embed/extmod/modtrezorcrypto/trezor-crypto/blake2b.c',
+    'embed/extmod/modtrezorcrypto/trezor-crypto/blake2s.c',
+    'embed/extmod/modtrezorcrypto/trezor-crypto/curves.c',
+    'embed/extmod/modtrezorcrypto/trezor-crypto/ecdsa.c',
+    'embed/extmod/modtrezorcrypto/trezor-crypto/ed25519-donna/ed25519.c',
+    'embed/extmod/modtrezorcrypto/trezor-crypto/hmac.c',
+    'embed/extmod/modtrezorcrypto/trezor-crypto/nist256p1.c',
+    'embed/extmod/modtrezorcrypto/trezor-crypto/pbkdf2.c',
+    'embed/extmod/modtrezorcrypto/trezor-crypto/ripemd160.c',
+    'embed/extmod/modtrezorcrypto/trezor-crypto/secp256k1.c',
+    'embed/extmod/modtrezorcrypto/trezor-crypto/sha2.c',
+    'embed/extmod/modtrezorcrypto/trezor-crypto/sha3.c',
+]
+
+# modtrezorio
+SOURCE_MOD += [
+    'embed/extmod/modtrezorio/modtrezorio.c',
+]
+
+# modtrezormsg
+SOURCE_MOD += [
+    'embed/unix/touch.c',
+    'embed/extmod/modtrezormsg/modtrezormsg.c',
+]
+
+# modtrezorui
+CPPDEFINES_MOD += [('QR_MAX_VERSION', '0')]
+SOURCE_MOD += [
+    'embed/extmod/modtrezorui/display.c',
+    'embed/extmod/modtrezorui/inflate.c',
+    'embed/extmod/modtrezorui/font_bitmap.c',
+    'embed/extmod/modtrezorui/font_roboto_bold_20.c',
+    'embed/extmod/modtrezorui/font_roboto_regular_20.c',
+    'embed/extmod/modtrezorui/font_robotomono_regular_20.c',
+    'embed/extmod/modtrezorui/modtrezorui.c',
+    'embed/extmod/modtrezorui/trezor-qrenc/qr_encode.c',
+]
+LIBS_MOD += ['SDL2', 'SDL2_image']
+
+# modtrezorutils
+SOURCE_MOD += [
+    'embed/extmod/modtrezorutils/modtrezorutils.c',
+]
+
+# modutime
+# SOURCE_MOD += [
+#     'embed/firmware/modutime.c',
+# ]
+
+SOURCE_MICROPYTHON = [
+    'vendor/micropython/extmod/modubinascii.c',
+    'vendor/micropython/extmod/moductypes.c',
+    'vendor/micropython/extmod/moduheapq.c',
+    'vendor/micropython/extmod/modujson.c',
+    'vendor/micropython/extmod/modure.c',
+    'vendor/micropython/extmod/modutimeq.c',
+    'vendor/micropython/extmod/moduzlib.c',
+    'vendor/micropython/extmod/utime_mphal.c',
+    'vendor/micropython/lib/mp-readline/readline.c',
+    'vendor/micropython/lib/timeutils/timeutils.c',
+    'vendor/micropython/py/argcheck.c',
+    'vendor/micropython/py/asmarm.c',
+    'vendor/micropython/py/asmbase.c',
+    'vendor/micropython/py/asmthumb.c',
+    'vendor/micropython/py/asmx64.c',
+    'vendor/micropython/py/asmx86.c',
+    'vendor/micropython/py/asmxtensa.c',
+    'vendor/micropython/py/bc.c',
+    'vendor/micropython/py/binary.c',
+    'vendor/micropython/py/builtinevex.c',
+    'vendor/micropython/py/builtinhelp.c',
+    'vendor/micropython/py/builtinimport.c',
+    'vendor/micropython/py/compile.c',
+    'vendor/micropython/py/emitbc.c',
+    'vendor/micropython/py/emitcommon.c',
+    'vendor/micropython/py/emitglue.c',
+    'vendor/micropython/py/emitinlinethumb.c',
+    'vendor/micropython/py/emitinlinextensa.c',
+    'vendor/micropython/py/formatfloat.c',
+    'vendor/micropython/py/frozenmod.c',
+    'vendor/micropython/py/gc.c',
+    'vendor/micropython/py/lexer.c',
+    'vendor/micropython/py/malloc.c',
+    'vendor/micropython/py/map.c',
+    'vendor/micropython/py/modarray.c',
+    'vendor/micropython/py/modbuiltins.c',
+    'vendor/micropython/py/modcmath.c',
+    'vendor/micropython/py/modcollections.c',
+    'vendor/micropython/py/modgc.c',
+    'vendor/micropython/py/modio.c',
+    'vendor/micropython/py/modmath.c',
+    'vendor/micropython/py/modmicropython.c',
+    'vendor/micropython/py/modstruct.c',
+    'vendor/micropython/py/modsys.c',
+    'vendor/micropython/py/modthread.c',
+    'vendor/micropython/py/moduerrno.c',
+    'vendor/micropython/py/mpprint.c',
+    'vendor/micropython/py/mpstate.c',
+    'vendor/micropython/py/mpz.c',
+    'vendor/micropython/py/nativeglue.c',
+    'vendor/micropython/py/nlrsetjmp.c',
+    'vendor/micropython/py/nlrthumb.c',
+    'vendor/micropython/py/nlrx64.c',
+    'vendor/micropython/py/nlrx86.c',
+    'vendor/micropython/py/nlrxtensa.c',
+    'vendor/micropython/py/obj.c',
+    'vendor/micropython/py/objarray.c',
+    'vendor/micropython/py/objattrtuple.c',
+    'vendor/micropython/py/objbool.c',
+    'vendor/micropython/py/objboundmeth.c',
+    'vendor/micropython/py/objcell.c',
+    'vendor/micropython/py/objclosure.c',
+    'vendor/micropython/py/objcomplex.c',
+    'vendor/micropython/py/objdict.c',
+    'vendor/micropython/py/objenumerate.c',
+    'vendor/micropython/py/objexcept.c',
+    'vendor/micropython/py/objfilter.c',
+    'vendor/micropython/py/objfloat.c',
+    'vendor/micropython/py/objfun.c',
+    'vendor/micropython/py/objgenerator.c',
+    'vendor/micropython/py/objgetitemiter.c',
+    'vendor/micropython/py/objint_longlong.c',
+    'vendor/micropython/py/objint_mpz.c',
+    'vendor/micropython/py/objint.c',
+    'vendor/micropython/py/objlist.c',
+    'vendor/micropython/py/objmap.c',
+    'vendor/micropython/py/objmodule.c',
+    'vendor/micropython/py/objnamedtuple.c',
+    'vendor/micropython/py/objnone.c',
+    'vendor/micropython/py/objobject.c',
+    'vendor/micropython/py/objpolyiter.c',
+    'vendor/micropython/py/objproperty.c',
+    'vendor/micropython/py/objrange.c',
+    'vendor/micropython/py/objreversed.c',
+    'vendor/micropython/py/objset.c',
+    'vendor/micropython/py/objsingleton.c',
+    'vendor/micropython/py/objslice.c',
+    'vendor/micropython/py/objstr.c',
+    'vendor/micropython/py/objstringio.c',
+    'vendor/micropython/py/objstrunicode.c',
+    'vendor/micropython/py/objtuple.c',
+    'vendor/micropython/py/objtype.c',
+    'vendor/micropython/py/objzip.c',
+    'vendor/micropython/py/opmethods.c',
+    'vendor/micropython/py/parse.c',
+    'vendor/micropython/py/parsenum.c',
+    'vendor/micropython/py/parsenumbase.c',
+    'vendor/micropython/py/persistentcode.c',
+    'vendor/micropython/py/qstr.c',
+    'vendor/micropython/py/reader.c',
+    'vendor/micropython/py/repl.c',
+    'vendor/micropython/py/runtime_utils.c',
+    'vendor/micropython/py/runtime.c',
+    'vendor/micropython/py/scope.c',
+    'vendor/micropython/py/scheduler.c',
+    'vendor/micropython/py/sequence.c',
+    'vendor/micropython/py/showbc.c',
+    'vendor/micropython/py/smallint.c',
+    'vendor/micropython/py/stackctrl.c',
+    'vendor/micropython/py/stream.c',
+    'vendor/micropython/py/unicode.c',
+    'vendor/micropython/py/vm.c',
+    'vendor/micropython/py/vstr.c',
+    'vendor/micropython/py/warning.c',
+]
+
+SOURCE_UNIX = [
+    'vendor/micropython/unix/main.c',
+    'vendor/micropython/unix/gccollect.c',
+    'vendor/micropython/unix/unix_mphal.c',
+    'vendor/micropython/unix/mpthreadport.c',
+    'vendor/micropython/unix/input.c',
+    'vendor/micropython/unix/file.c',
+    'vendor/micropython/unix/modos.c',
+    'vendor/micropython/unix/modtime.c',
+    'vendor/micropython/unix/moduselect.c',
+    'vendor/micropython/unix/alloc.c',
+    'embed/unix/common.c',
+]
+
+SOURCE_EMIT_NATIVE = ['vendor/micropython/py/emitnative.c']
+
+SOURCE_QSTR = SOURCE_MOD + SOURCE_MICROPYTHON + SOURCE_UNIX + SOURCE_EMIT_NATIVE
+
+env = Environment()
+
+env.Tool('micropython')
+
+env.Replace(
+    SED='sed',
+    AS='as',
+    AR='ar',
+    CC='gcc',
+    LINK='ld',
+    SIZE='size',
+    STRIP='strip',
+    OBJCOPY='objcopy', )
+
+env.Replace(
+    CCFLAGS='-Os '
+    '-g3 '
+    '-std=gnu99 -Wall -Werror -Wuninitialized '
+    '-fdata-sections -ffunction-sections ' + CCFLAGS_MOD,
+    CCFLAGS_QSTR='-DNO_QSTR -DN_X64 -DN_X86 -DN_THUMB -DN_ARM -DN_XTENSA',
+    LIBS=LIBS_MOD,
+    CPPPATH=[
+        '.',
+        'embed/unix',
+        'embed/extmod/modtrezorui',
+        'vendor/micropython',
+        'vendor/micropython/unix',
+        'vendor/micropython/lib/mp-readline',
+    ] + CPPPATH_MOD,
+    CPPDEFINES=[
+        'MICROPY_USE_READLINE',
+        'TREZOR_UNIX',
+        'UNIX',
+        ('MP_CONFIGFILE', '\\"embed/unix/mpconfigport.h\\"'),
+    ] + CPPDEFINES_MOD, )
+
+env.Replace(
+    PYTHON='python',
+    PYTHONPATH='vendor/micropython/py',
+    MAKEQSTRDEFS='$PYTHON vendor/micropython/py/makeqstrdefs.py',
+    MAKEQSTRDATA='$PYTHON vendor/micropython/py/makeqstrdata.py',
+    MAKEVERSIONHDR='$PYTHON vendor/micropython/py/makeversionhdr.py',
+    MPY_CROSS='vendor/micropython/mpy-cross/mpy-cross',
+    MPY_TOOL='$PYTHON vendor/micropython/tools/mpy-tool.py',
+    MAKE_FROZEN='$PYTHON vendor/micropython/tools/make-frozen.py', )
+
+#
+# Micropython version
+#
+
+hdr_version = env.Command(
+    target='genhdr/mpversion.h',
+    source='',
+    action='$MAKEVERSIONHDR $TARGET', )
+
+#
+# Qstrings
+#
+
+qstr_micropython = 'vendor/micropython/py/qstrdefs.h'
+
+qstr_collected = env.CollectQstr(
+    target='genhdr/qstrdefs.collected.h', source=SOURCE_QSTR)
+
+qstr_preprocessed = env.PreprocessQstr(
+    target='genhdr/qstrdefs.preprocessed.h',
+    source=[qstr_micropython, qstr_collected])
+
+qstr_generated = env.GenerateQstrDefs(
+    target='genhdr/qstrdefs.generated.h', source=qstr_preprocessed)
+
+env.Ignore(qstr_collected, qstr_generated)
+
+#
+# Program objects
+#
+
+obj_program = []
+obj_program += env.Object(source=SOURCE_MOD)
+obj_program += env.Object(source=SOURCE_MICROPYTHON)
+obj_program += env.Object(source=SOURCE_UNIX)
+
+obj_program += env.Object(
+    source=SOURCE_EMIT_NATIVE,
+    target='vendor/micropython/py/emitnx64.o',
+    CPPDEFINES=[env['CPPDEFINES'], 'N_X64'], )
+
+obj_program += env.Object(
+    source=SOURCE_EMIT_NATIVE,
+    target='vendor/micropython/py/emitnx86.o',
+    CPPDEFINES=[env['CPPDEFINES'], 'N_X86'], )
+
+obj_program += env.Object(
+    source=SOURCE_EMIT_NATIVE,
+    target='vendor/micropython/py/emitnthumb.o',
+    CPPDEFINES=[env['CPPDEFINES'], 'N_THUMB'], )
+
+env.Depends(obj_program, qstr_generated)
+
+program = env.Command(
+    target='micropython',
+    source=obj_program,
+    action='$CC -o $TARGET $SOURCES $_LIBDIRFLAGS $_LIBFLAGS $LINKFLAGS', )
diff --git a/SConstruct b/SConstruct
index f6535843f..34202f49c 100644
--- a/SConstruct
+++ b/SConstruct
@@ -1,3 +1,4 @@
 # pylint: disable=E0602
 
-SConscript('SConscript', variant_dir='build/firmware', src='.', duplicate=False)
+SConscript('SConscript.firmware', variant_dir='build/firmware', duplicate=False)
+SConscript('SConscript.unix', variant_dir='build/unix', duplicate=False)
diff --git a/embed/unix/mpconfigport.h b/embed/unix/mpconfigport.h
index e682645b8..f0c4dd134 100644
--- a/embed/unix/mpconfigport.h
+++ b/embed/unix/mpconfigport.h
@@ -102,9 +102,9 @@
 #endif
 #define MICROPY_PY_CMATH            (1)
 #define MICROPY_PY_IO_FILEIO        (1)
-#define MICROPY_PY_IO_RESOURCE_STREAM (1)
+#define MICROPY_PY_IO_RESOURCE_STREAM (0)
 #define MICROPY_PY_GC_COLLECT_RETVAL (1)
-#define MICROPY_MODULE_FROZEN_STR   (1)
+#define MICROPY_MODULE_FROZEN_STR   (0)
 
 #define MICROPY_STACKLESS           (0)
 #define MICROPY_STACKLESS_STRICT    (0)
@@ -119,19 +119,19 @@
 #define MICROPY_PY_URE              (1)
 #define MICROPY_PY_UHEAPQ           (1)
 #define MICROPY_PY_UTIMEQ           (1)
-#define MICROPY_PY_UHASHLIB         (1)
+#define MICROPY_PY_UHASHLIB         (0)
 #if MICROPY_PY_USSL && MICROPY_SSL_AXTLS
-#define MICROPY_PY_UHASHLIB_SHA1    (1)
+#define MICROPY_PY_UHASHLIB_SHA1    (0)
 #endif
 #define MICROPY_PY_UBINASCII        (1)
 #define MICROPY_PY_UBINASCII_CRC32  (1)
-#define MICROPY_PY_URANDOM          (1)
+#define MICROPY_PY_URANDOM          (0)
 #ifndef MICROPY_PY_USELECT_POSIX
-#define MICROPY_PY_USELECT_POSIX    (1)
+#define MICROPY_PY_USELECT_POSIX    (0)
 #endif
-#define MICROPY_PY_WEBSOCKET        (1)
-#define MICROPY_PY_MACHINE          (1)
-#define MICROPY_PY_MACHINE_PULSE    (1)
+#define MICROPY_PY_WEBSOCKET        (0)
+#define MICROPY_PY_MACHINE          (0)
+#define MICROPY_PY_MACHINE_PULSE    (0)
 #define MICROPY_MACHINE_MEM_GET_READ_ADDR   mod_machine_mem_get_addr
 #define MICROPY_MACHINE_MEM_GET_WRITE_ADDR  mod_machine_mem_get_addr
 
@@ -146,6 +146,7 @@
 #define MICROPY_FATFS_RPATH            (2)
 #define MICROPY_FATFS_MAX_SS           (4096)
 #define MICROPY_FATFS_LFN_CODE_PAGE    (437) /* 1=SFN/ANSI 437=LFN/U.S.(OEM) */
+#define MICROPY_VFS                    (0)
 #define MICROPY_VFS_FAT                (0)
 
 // Define to MICROPY_ERROR_REPORTING_DETAILED to get function, etc.
@@ -169,7 +170,6 @@
 #define MICROPY_KBD_EXCEPTION       (1)
 #define MICROPY_ASYNC_KBD_INTR      (1)
 
-extern const struct _mp_obj_module_t mp_module_machine;
 extern const struct _mp_obj_module_t mp_module_os;
 extern const struct _mp_obj_module_t mp_module_uos_vfs;
 extern const struct _mp_obj_module_t mp_module_uselect;
@@ -258,7 +258,6 @@ extern const struct _mp_obj_module_t mp_module_trezorutils;
     MICROPY_PY_JNI_DEF \
     MICROPY_PY_UTIME_DEF \
     MICROPY_PY_SOCKET_DEF \
-    { MP_ROM_QSTR(MP_QSTR_umachine), MP_ROM_PTR(&mp_module_machine) }, \
     { MP_ROM_QSTR(MP_QSTR_uos), MP_ROM_PTR(&mp_module_os) }, \
     MICROPY_PY_UOS_VFS_DEF \
     MICROPY_PY_USELECT_DEF \
diff --git a/site_scons/site_tools/micropython/__init__.py b/site_scons/site_tools/micropython/__init__.py
index 35c332f76..1c64500d4 100644
--- a/site_scons/site_tools/micropython/__init__.py
+++ b/site_scons/site_tools/micropython/__init__.py
@@ -20,7 +20,7 @@ def generate(env):
         action='$MAKEQSTRDATA $SOURCE > $TARGET', )
 
     env['BUILDERS']['FrozenModule'] = SCons.Builder.Builder(
-        action='$MPY_CROSS -o $TARGET -s $SOURCE $SOURCE',
+        action='$MPY_CROSS -o $TARGET $SOURCE',
         suffix='.mpy',
         single_source=True, )