diff --git a/CHANGELOG.md b/CHANGELOG.md
index 12bcaeb7a..3396ad5b7 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,9 @@
 - Fixed Ultrasonic Sensor and Color Sensor turning off when a
   user script ends ([support#456]).
 
+### Changed:
+- Updated to MicroPython v1.17.
+
 [support#456]: https://github.com/pybricks/support/issues/456
 
 ## [3.1.0a4] - 2021-08-30
diff --git a/bricks/ev3dev/Makefile b/bricks/ev3dev/Makefile
index 030358fe9..332d162b7 100644
--- a/bricks/ev3dev/Makefile
+++ b/bricks/ev3dev/Makefile
@@ -139,9 +139,9 @@ LDFLAGS += $(LDFLAGS_MOD) $(LDFLAGS_ARCH) -lm $(LDFLAGS_EXTRA)
 LDFLAGS += -lpthread
 
 ifeq ($(MICROPY_USE_READLINE),1)
-INC +=  -I$(TOP)/lib/mp-readline
+INC +=  -I$(TOP)/shared/readline
 CFLAGS_MOD += -DMICROPY_USE_READLINE=1
-LIB_SRC_C_EXTRA += mp-readline/readline.c
+SHARED_SRC_C_EXTRA += readline/readline.c
 endif
 ifeq ($(MICROPY_PY_TERMIOS),1)
 CFLAGS_MOD += -DMICROPY_PY_TERMIOS=1
@@ -216,11 +216,11 @@ SRC_C = $(addprefix ports/unix/,\
 
 SRC_C += $(SRC_MOD)
 
-LIB_SRC_C = $(addprefix lib/,\
-	$(LIB_SRC_C_EXTRA) \
+SHARED_SRC_C = $(addprefix shared/,\
+	runtime/gchelper_generic.c \
+	runtime/pyexec.c \
 	timeutils/timeutils.c \
-	utils/gchelper_generic.c \
-	utils/pyexec.c \
+	$(SHARED_SRC_C_EXTRA) \
 	)
 
 # Pybricks port core source files
@@ -338,14 +338,14 @@ PYBRICKS_LIB_SRC_C = $(addprefix lib/,\
 
 OBJ = $(PY_O)
 OBJ += $(addprefix $(BUILD)/, $(SRC_C:.c=.o))
-OBJ += $(addprefix $(BUILD)/, $(LIB_SRC_C:.c=.o))
+OBJ += $(addprefix $(BUILD)/, $(SHARED_SRC_C:.c=.o))
 OBJ += $(addprefix $(BUILD)/, $(EXTMOD_SRC_C:.c=.o))
 OBJ += $(addprefix $(BUILD)/, $(PYBRICKS_PYBRICKS_SRC_C:.c=.o))
 OBJ += $(addprefix $(BUILD)/, $(PYBRICKS_SRC_C:.c=.o))
 OBJ += $(addprefix $(BUILD)/, $(PYBRICKS_LIB_SRC_C:.c=.o))
 
 # List of sources for qstr extraction
-SRC_QSTR += $(SRC_C) $(LIB_SRC_C) $(EXTMOD_SRC_C) $(PYBRICKS_SRC_C) $(PYBRICKS_PYBRICKS_SRC_C)
+SRC_QSTR += $(SRC_C) $(SHARED_SRC_C) $(EXTMOD_SRC_C) $(PYBRICKS_SRC_C) $(PYBRICKS_PYBRICKS_SRC_C)
 # Append any auto-generated sources that are needed by sources listed in
 # SRC_QSTR
 SRC_QSTR_AUTO_DEPS +=
diff --git a/bricks/ev3dev/ev3dev_mphal.h b/bricks/ev3dev/ev3dev_mphal.h
index f3ea20b75..98596681b 100644
--- a/bricks/ev3dev/ev3dev_mphal.h
+++ b/bricks/ev3dev/ev3dev_mphal.h
@@ -36,7 +36,7 @@ void mp_hal_stdio_mode_orig(void);
 
 #if MICROPY_USE_READLINE == 1 && MICROPY_PY_BUILTINS_INPUT
 #include "py/misc.h"
-#include "lib/mp-readline/readline.h"
+#include "shared/readline/readline.h"
 // For built-in input() we need to wrap the standard readline() to enable raw mode
 #define mp_hal_readline mp_hal_readline
 static inline int mp_hal_readline(vstr_t *vstr, const char *p) {
diff --git a/bricks/ev3rt/Makefile b/bricks/ev3rt/Makefile
index f02214664..0287ef0ad 100644
--- a/bricks/ev3rt/Makefile
+++ b/bricks/ev3rt/Makefile
@@ -98,9 +98,9 @@ endif
 endif
 
 ifeq ($(MICROPY_USE_READLINE),1)
-INC +=  -I$(MPTOP)/lib/mp-readline
+INC +=  -I$(MPTOP)/shared/readline
 CFLAGS_MOD += -DMICROPY_USE_READLINE=1
-LIB_SRC_C_EXTRA += mp-readline/readline.c
+SHARED_SRC_C_EXTRA += readline/readline.c
 endif
 ifeq ($(MICROPY_USE_READLINE),2)
 CFLAGS_MOD += -DMICROPY_USE_READLINE=2
@@ -159,11 +159,11 @@ SRC_C = $(addprefix ports/unix/,\
 	mphal.c \
 	)
 
-LIB_SRC_C = $(addprefix lib/,\
-	$(LIB_SRC_C_EXTRA) \
-	utils/printf.c \
-	utils/interrupt_char.c \
+SHARED_SRC_C = $(addprefix shared/,\
+	runtime/printf.c \
+	runtime/interrupt_char.c \
 	timeutils/timeutils.c \
+	$(SHARED_SRC_C_EXTRA) \
 	)
 
 ifeq ($(MICROPY_FATFS),1)
@@ -175,10 +175,11 @@ endif
 
 OBJ = $(PY_O)
 OBJ += $(addprefix $(BUILD)/, $(SRC_C:.c=.o))
+OBJ += $(addprefix $(BUILD)/, $(SHARED_SRC_C:.c=.o))
 OBJ += $(addprefix $(BUILD)/, $(LIB_SRC_C:.c=.o))
 
 # List of sources for qstr extraction
-SRC_QSTR += $(SRC_C) $(LIB_SRC_C)
+SRC_QSTR += $(SRC_C) $(SHARED_SRC_C) $(LIB_SRC_C)
 # Append any auto-generated sources that are needed by sources listed in
 # SRC_QSTR
 SRC_QSTR_AUTO_DEPS +=
diff --git a/bricks/ev3rt/mphal.c b/bricks/ev3rt/mphal.c
index 752fef15b..0bf7b3ad3 100644
--- a/bricks/ev3rt/mphal.c
+++ b/bricks/ev3rt/mphal.c
@@ -38,7 +38,7 @@
 #include "py/repl.h"
 #include "py/gc.h"
 #include "py/mperrno.h"
-#include "lib/utils/pyexec.h"
+#include "shared/runtime/pyexec.h"
 
 mp_import_stat_t mp_import_stat(const char *path) {
     return MP_IMPORT_STAT_NO_EXIST;
diff --git a/bricks/nxt/Makefile b/bricks/nxt/Makefile
index c4393d45c..3cec3cdb2 100644
--- a/bricks/nxt/Makefile
+++ b/bricks/nxt/Makefile
@@ -39,6 +39,7 @@ QSTR_GLOBAL_DEPENDENCIES =
 # MicroPython feature configurations
 MICROPY_ROM_TEXT_COMPRESSION ?= 1
 
+MPY_CROSS = ../../micropython/mpy-cross/mpy-cross
 MPY_CROSS_FLAGS += -mno-unicode
 
 # include py core make definitions
@@ -96,16 +97,16 @@ SRC_C = \
 # if we don't do it this way. So we need to be very careful about name clashes
 # between the top level directory and the micropython/ subdirectory.
 
-SRC_C += $(addprefix lib/,\
+SRC_C += $(addprefix shared/,\
 	libc/string0.c \
-	mp-readline/readline.c \
-	utils/interrupt_char.c \
-	utils/pyexec.c \
-	utils/stdout_helpers.c \
+	readline/readline.c \
+	runtime/interrupt_char.c \
+	runtime/pyexec.c \
+	runtime/stdout_helpers.c \
 	)
 
 SRC_S = \
-	lib/utils/gchelper_arm7tdmi.s \
+	shared/runtime/gchelper_arm7tdmi.s \
 
 SRC_C_NXT := $(addprefix nxt-firmware-drivers/nxt/,\
 	aic.c \
diff --git a/bricks/nxt/main.c b/bricks/nxt/main.c
index dbb35f564..53194faa6 100644
--- a/bricks/nxt/main.c
+++ b/bricks/nxt/main.c
@@ -21,8 +21,8 @@
 #include "py/mperrno.h"
 #include "py/persistentcode.h"
 #include "py/stackctrl.h"
-#include "lib/utils/pyexec.h"
-#include "lib/utils/interrupt_char.h"
+#include "shared/runtime/pyexec.h"
+#include "shared/runtime/interrupt_char.h"
 
 #include "py/mphal.h"
 
@@ -202,7 +202,7 @@ int main(int argc, char **argv) {
 
 // defined in linker script
 extern uint32_t _estack;
-// defined in lib/utils/gchelper_arm7tdmi.s
+// defined in shared/runtime/gchelper_arm7tdmi.s
 extern uintptr_t gc_helper_get_regs_and_sp(uintptr_t *regs);
 
 void gc_collect(void) {
diff --git a/bricks/stm32/main.c b/bricks/stm32/main.c
index 51dd8d6d3..4ff654c80 100644
--- a/bricks/stm32/main.c
+++ b/bricks/stm32/main.c
@@ -15,10 +15,10 @@
 #include <pybricks/common.h>
 #include <pybricks/util_mp/pb_obj_helper.h>
 
-#include "lib/mp-readline/readline.h"
-#include "lib/utils/gchelper.h"
-#include "lib/utils/interrupt_char.h"
-#include "lib/utils/pyexec.h"
+#include "shared/readline/readline.h"
+#include "shared/runtime/gchelper.h"
+#include "shared/runtime/interrupt_char.h"
+#include "shared/runtime/pyexec.h"
 #include "py/compile.h"
 #include "py/gc.h"
 #include "py/mperrno.h"
diff --git a/bricks/stm32/stm32.mk b/bricks/stm32/stm32.mk
index f6df0c40e..cc1da5735 100644
--- a/bricks/stm32/stm32.mk
+++ b/bricks/stm32/stm32.mk
@@ -148,6 +148,7 @@ CFLAGS += -D$(PB_CMSIS_MCU)
 CFLAGS += -DSTM32_H='<stm32$(PB_MCU_SERIES_LCASE)xx.h>'
 CFLAGS += -DSTM32_HAL_H='<stm32$(PB_MCU_SERIES_LCASE)xx_hal.h>'
 
+MPY_CROSS = ../../micropython/mpy-cross/mpy-cross
 # TODO: probably only need no-unicode on movehub
 MPY_CROSS_FLAGS += -mno-unicode
 
@@ -167,23 +168,23 @@ SRC_C = $(addprefix bricks/stm32/,\
 # if we don't do it this way. So we need to be very careful about name clashes
 # between the top level directory and the micropython/ subdirectory.
 
-SRC_C += $(addprefix lib/,\
+SRC_C += $(addprefix shared/,\
 	libc/string0.c \
-	mp-readline/readline.c \
-	utils/gchelper_native.c \
-	utils/interrupt_char.c \
-	utils/pyexec.c \
-	utils/stdout_helpers.c \
-	utils/sys_stdio_mphal.c \
+	readline/readline.c \
+	runtime/gchelper_native.c \
+	runtime/interrupt_char.c \
+	runtime/pyexec.c \
+	runtime/stdout_helpers.c \
+	runtime/sys_stdio_mphal.c \
 	)
 
 SRC_S = \
 	lib/pbio/platform/$(PBIO_PLATFORM)/startup.s \
 
 ifeq ($(PB_MCU_SERIES),F0)
-	SRC_S += lib/utils/gchelper_m0.s
+	SRC_S += shared/runtime/gchelper_m0.s
 else
-	SRC_S += lib/utils/gchelper_m3.s
+	SRC_S += shared/runtime/gchelper_m3.s
 endif
 
 # Pybricks modules
diff --git a/lib/pbio/drv/bluetooth/pybricks_service_server.h b/lib/pbio/drv/bluetooth/pybricks_service_server.h
index e03ea26c2..a005ac602 100644
--- a/lib/pbio/drv/bluetooth/pybricks_service_server.h
+++ b/lib/pbio/drv/bluetooth/pybricks_service_server.h
@@ -75,4 +75,3 @@ void pybricks_service_server_request_can_send_now(btstack_context_callback_regis
 int pybricks_service_server_send(hci_con_handle_t con_handle, const uint8_t *data, uint16_t size);
 
 #endif // PYBRICKS_SERVICE_SERVER_H
-
diff --git a/lib/pbio/platform/move_hub/bluenrg_conf.h b/lib/pbio/platform/move_hub/bluenrg_conf.h
index b96989886..9f37344a5 100644
--- a/lib/pbio/platform/move_hub/bluenrg_conf.h
+++ b/lib/pbio/platform/move_hub/bluenrg_conf.h
@@ -8,4 +8,3 @@
 #define HCI_MAX_PAYLOAD_SIZE        127
 
 #endif /* _BLUENRG_CONF_H_ */
-
diff --git a/micropython b/micropython
index c22558dde..b3e725ab9 160000
--- a/micropython
+++ b/micropython
@@ -1 +1 @@
-Subproject commit c22558ddefea6ea8fd682349f46b2d6fcb1987df
+Subproject commit b3e725ab9666c237362e9cf39959b4813501e64f
diff --git a/npm/mpy-cross/Makefile b/npm/mpy-cross/Makefile
index 7b932b9b4..476c54fa2 100644
--- a/npm/mpy-cross/Makefile
+++ b/npm/mpy-cross/Makefile
@@ -122,7 +122,7 @@ SRC = $(addprefix $(MICROPYTHON_DIR)/, \
 	py/frozenmod.c \
 	mpy-cross/main.c \
 	mpy-cross/gccollect.c \
-	lib/utils/gchelper_generic.c \
+	shared/runtime/gchelper_generic.c \
 	)
 
 MPY_CROSS_BUILD := $(MICROPYTHON_DIR)/mpy-cross/build