diff --git a/ports/nrf/boards/memory.ld b/ports/nrf/boards/memory.ld
index 9c4c9c8bd1..df95b951b0 100644
--- a/ports/nrf/boards/memory.ld
+++ b/ports/nrf/boards/memory.ld
@@ -8,10 +8,12 @@ _head_size     = DEFINED(_sd_size) ? _sd_size : _bootloader_head_size;
 _head_ram      = DEFINED(_sd_ram)  ? _sd_ram : _bootloader_head_ram_size;
 _sd_size       = DEFINED(_sd_size) ? _sd_size : 0;
 _sd_ram        = DEFINED(_sd_ram)  ? _sd_ram : 0;
+_micropy_hw_romfs_part0_size = DEFINED(_micropy_hw_romfs_part0_size) ? _micropy_hw_romfs_part0_size : 0;
 _fs_size       = DEFINED(_fs_size) ? _fs_size : 64K; /* TODO: set to 0 if not using the filesystem */
-_app_size      = _flash_size - _head_size - _fs_size  - _bootloader_tail_size;
+_app_size      = _flash_size - _head_size - _micropy_hw_romfs_part0_size - _fs_size - _bootloader_tail_size;
 _app_start     = _head_size;
-_fs_start      = _head_size + _app_size;
+_micropy_hw_romfs_part0_start = _head_size + _app_size;
+_fs_start      = _micropy_hw_romfs_part0_start + _micropy_hw_romfs_part0_size;
 _fs_end        = _fs_start + _fs_size;
 _app_ram_start = 0x20000000 + _head_ram;
 _app_ram_size  = _ram_size - _head_ram;
diff --git a/ports/nrf/boards/nrf51x22_256k_16k.ld b/ports/nrf/boards/nrf51x22_256k_16k.ld
index 8a40ae0f17..4c54def8e8 100644
--- a/ports/nrf/boards/nrf51x22_256k_16k.ld
+++ b/ports/nrf/boards/nrf51x22_256k_16k.ld
@@ -6,6 +6,7 @@ GROUP(-lgcc -lc -lnosys)
 
 _flash_size = 256K;
 _ram_size = 16K;
+_micropy_hw_romfs_part0_size = 12K;
 
 /* Default stack size when there is no SoftDevice */
 _stack_size        = 4K;
diff --git a/ports/nrf/boards/nrf51x22_256k_32k.ld b/ports/nrf/boards/nrf51x22_256k_32k.ld
index 06c0914035..b61c2a5505 100644
--- a/ports/nrf/boards/nrf51x22_256k_32k.ld
+++ b/ports/nrf/boards/nrf51x22_256k_32k.ld
@@ -6,6 +6,7 @@ GROUP(-lgcc -lc -lnosys)
 
 _flash_size = 256K;
 _ram_size = 32K;
+_micropy_hw_romfs_part0_size = 12K;
 
 /* Default stack size when there is no SoftDevice */
 _stack_size        = 4K;
diff --git a/ports/nrf/boards/nrf52832_512k_64k.ld b/ports/nrf/boards/nrf52832_512k_64k.ld
index 22804df5cd..0599c9bda3 100644
--- a/ports/nrf/boards/nrf52832_512k_64k.ld
+++ b/ports/nrf/boards/nrf52832_512k_64k.ld
@@ -4,6 +4,7 @@
 
 _flash_size = 512K;
 _ram_size   = 64K;
+_micropy_hw_romfs_part0_size = 128K;
 
 /* produce a link error if there is not this amount of RAM for these sections */
 _stack_size = 8K;
diff --git a/ports/nrf/boards/nrf52840_1M_256k.ld b/ports/nrf/boards/nrf52840_1M_256k.ld
index 16d61af6a3..21d4518243 100644
--- a/ports/nrf/boards/nrf52840_1M_256k.ld
+++ b/ports/nrf/boards/nrf52840_1M_256k.ld
@@ -4,6 +4,7 @@
 
 _flash_size = 1M;
 _ram_size   = 256K;
+_micropy_hw_romfs_part0_size = 256K;
 
 /* produce a link error if there is not this amount of RAM for these sections */
 _stack_size = 8K;
diff --git a/ports/nrf/boards/nrf9160_1M_256k.ld b/ports/nrf/boards/nrf9160_1M_256k.ld
index 6347095a89..d8f0aa5cb0 100644
--- a/ports/nrf/boards/nrf9160_1M_256k.ld
+++ b/ports/nrf/boards/nrf9160_1M_256k.ld
@@ -7,6 +7,7 @@ _ram_size   = 256K;
 _sd_size = 0x00008000;
 _sd_ram  = 0x00020000;
 _fs_size = 80K;
+_micropy_hw_romfs_part0_size = 256K;
 
 /* produce a link error if there is not this amount of RAM for these sections */
 _stack_size = 32K;
diff --git a/ports/nrf/main.c b/ports/nrf/main.c
index 7278a646ab..1013005e19 100644
--- a/ports/nrf/main.c
+++ b/ports/nrf/main.c
@@ -177,22 +177,8 @@ soft_reset:
 
     #if MICROPY_HW_ENABLE_INTERNAL_FLASH_STORAGE
     flashbdev_init();
-
-    // Try to mount the flash on "/flash" and chdir to it for the boot-up directory.
-    mp_obj_t mount_point = MP_OBJ_NEW_QSTR(MP_QSTR__slash_flash);
-    int ret = mp_vfs_mount_and_chdir_protected((mp_obj_t)&nrf_flash_obj, mount_point);
-
-    if ((ret == -MP_ENODEV) || (ret == -MP_EIO)) {
-        pyexec_frozen_module("_mkfs.py", false); // Frozen script for formatting flash filesystem.
-        ret = mp_vfs_mount_and_chdir_protected((mp_obj_t)&nrf_flash_obj, mount_point);
-    }
-
-    if (ret != 0) {
-        printf("MPY: can't mount flash\n");
-    } else {
-        mp_obj_list_append(mp_sys_path, MP_OBJ_NEW_QSTR(MP_QSTR__slash_flash));
-        mp_obj_list_append(mp_sys_path, MP_OBJ_NEW_QSTR(MP_QSTR__slash_flash_slash_lib));
-    }
+    // Execute _boot.py to set up the filesystem.
+    pyexec_frozen_module("_boot.py", false);
     #endif
 
     #if MICROPY_MBFS
diff --git a/ports/nrf/modules/manifest.py b/ports/nrf/modules/manifest.py
index 7ba0f80d88..631ad19a8d 100644
--- a/ports/nrf/modules/manifest.py
+++ b/ports/nrf/modules/manifest.py
@@ -1,2 +1,2 @@
-module("_mkfs.py", base_path="$(PORT_DIR)/modules/scripts", opt=3)
+module("_boot.py", base_path="$(PORT_DIR)/modules/scripts", opt=3)
 include("$(MPY_DIR)/extmod/asyncio")
diff --git a/ports/nrf/modules/nrf/flashbdev.c b/ports/nrf/modules/nrf/flashbdev.c
index 41833b228e..b28314b4a6 100644
--- a/ports/nrf/modules/nrf/flashbdev.c
+++ b/ports/nrf/modules/nrf/flashbdev.c
@@ -183,12 +183,26 @@ static mp_obj_t nrf_flashbdev_make_new(const mp_obj_type_t *type, size_t n_args,
     return MP_OBJ_FROM_PTR(self);
 }
 
+static mp_int_t nrf_flashbdev_get_buffer(mp_obj_t self_in, mp_buffer_info_t *bufinfo, mp_uint_t flags) {
+    nrf_flash_obj_t *self = MP_OBJ_TO_PTR(self_in);
+    if (flags == MP_BUFFER_READ) {
+        bufinfo->buf = (void *)self->start;
+        bufinfo->len = self->len;
+        bufinfo->typecode = 'B';
+        return 0;
+    } else {
+        // Unsupported.
+        return 1;
+    }
+}
+
 MP_DEFINE_CONST_OBJ_TYPE(
     nrf_flashbdev_type,
     MP_QSTR_Flash,
     MP_TYPE_FLAG_NONE,
     make_new, nrf_flashbdev_make_new,
     print, nrf_flashbdev_print,
+    buffer, nrf_flashbdev_get_buffer,
     locals_dict, &nrf_flashbdev_locals_dict
     );
 
@@ -202,4 +216,34 @@ void flashbdev_init(void) {
     nrf_flash_obj.len = num_pages * FLASH_PAGESIZE;
 }
 
+#if MICROPY_VFS_ROM
+
+extern byte _micropy_hw_romfs_part0_start[];
+extern byte _micropy_hw_romfs_part0_size[];
+
+#define MICROPY_HW_ROMFS_BASE ((uint32_t)_micropy_hw_romfs_part0_start)
+#define MICROPY_HW_ROMFS_BYTES ((uint32_t)_micropy_hw_romfs_part0_size)
+
+static nrf_flash_obj_t nrf_flash_romfs_obj = {
+    .base = { &nrf_flashbdev_type },
+    .start = MICROPY_HW_ROMFS_BASE, // Get from MCU-Specific loader script.
+    .len = MICROPY_HW_ROMFS_BYTES, // Get from MCU-Specific loader script.
+};
+
+mp_obj_t mp_vfs_rom_ioctl(size_t n_args, const mp_obj_t *args) {
+    if (MICROPY_HW_ROMFS_BYTES <= 0) {
+        return MP_OBJ_NEW_SMALL_INT(-MP_EINVAL);
+    }
+    switch (mp_obj_get_int(args[0])) {
+        case MP_VFS_ROM_IOCTL_GET_NUMBER_OF_SEGMENTS:
+            return MP_OBJ_NEW_SMALL_INT(1);
+        case MP_VFS_ROM_IOCTL_GET_SEGMENT:
+            return MP_OBJ_FROM_PTR(&nrf_flash_romfs_obj);
+        default:
+            return MP_OBJ_NEW_SMALL_INT(-MP_EINVAL);
+    }
+}
+
+#endif // MICROPY_VFS_ROM
+
 #endif // MICROPY_PY_NRF && MICROPY_HW_ENABLE_INTERNAL_FLASH_STORAGE
diff --git a/ports/nrf/modules/scripts/_boot.py b/ports/nrf/modules/scripts/_boot.py
new file mode 100644
index 0000000000..793c56ee14
--- /dev/null
+++ b/ports/nrf/modules/scripts/_boot.py
@@ -0,0 +1,28 @@
+def setup_fs():
+    import gc
+    import vfs
+    import sys
+    import nrf
+    import os
+
+    fs_type = getattr(vfs, "VfsLfs2", getattr(vfs, "VfsLfs1", getattr(vfs, "VfsFat", None)))
+    try:
+        bdev = nrf.Flash()
+        vfs.mount(bdev, "/flash")
+    except:
+        if fs_type is not None:
+            try:
+                fs_type.mkfs(bdev)
+                vfs.mount(bdev, "/flash")
+            except:
+                return
+
+    os.chdir("/flash")
+    sys.path.append("/flash")
+    sys.path.append("/flash/lib")
+
+    gc.collect()
+
+
+setup_fs()
+del setup_fs
diff --git a/ports/nrf/modules/scripts/_mkfs.py b/ports/nrf/modules/scripts/_mkfs.py
deleted file mode 100644
index 601f9558eb..0000000000
--- a/ports/nrf/modules/scripts/_mkfs.py
+++ /dev/null
@@ -1,23 +0,0 @@
-import vfs, nrf
-
-try:
-    from vfs import VfsLfs1
-
-    vfs.VfsLfs1.mkfs(nrf.Flash())
-except ImportError:
-    try:
-        from vfs import VfsLfs2
-
-        vfs.VfsLfs2.mkfs(nrf.Flash())
-    except ImportError:
-        try:
-            from vfs import VfsFat
-
-            vfs.VfsFat.mkfs(nrf.Flash())
-        except ImportError:
-            pass
-        except OSError as e:
-            if e.args[0] == 5:  # I/O Error
-                flashbdev_size = (nrf.Flash.ioctl(4, 0) * nrf.Flash.ioctl(5, 0)) // 1024
-                print()
-                print("Is `FS_SIZE=%iK` enough for FAT filesystem?" % flashbdev_size)
diff --git a/ports/nrf/mpconfigport.h b/ports/nrf/mpconfigport.h
index cce3f86cfd..bb517c19c5 100644
--- a/ports/nrf/mpconfigport.h
+++ b/ports/nrf/mpconfigport.h
@@ -69,6 +69,11 @@
 #define MICROPY_VFS                        (CORE_FEAT)
 #endif
 
+// VfsROM filesystem
+#ifndef MICROPY_VFS_ROM
+#define MICROPY_VFS_ROM                    (CORE_FEAT)
+#endif
+
 // micro:bit filesystem
 #ifndef MICROPY_MBFS
 #define MICROPY_MBFS                       (!MICROPY_VFS)