diff --git a/.github/workflows/micropython.yml b/.github/workflows/micropython.yml
index 5026a8d..752d298 100644
--- a/.github/workflows/micropython.yml
+++ b/.github/workflows/micropython.yml
@@ -34,11 +34,14 @@ jobs:
       # MicroPython version will be contained in github.event.release.tag_name for releases
       RELEASE_FILE: ${{ matrix.name }}-${{ github.event.release.tag_name || github.sha }}-micropython
       PIMORONI_PICO_DIR: "${{ github.workspace }}/pimoroni-pico"
-      MICROPY_BOARD_DIR: "${{ github.workspace }}/src-${{ github.sha }}/${{ matrix.BOARD }}"
       USER_C_MODULES: "${{ github.workspace }}/src-${{ github.sha }}/modules/${{ matrix.modules }}.cmake"
+      USER_FS_MANIFEST: "${{ github.workspace }}/src-${{ github.sha }}/modules/${{ matrix.modules }}.txt"
+      USER_FS_SOURCE: "${{ github.workspace }}/src-${{ github.sha }}/modules/littlefs"
       TAG_OR_SHA: ${{ github.event.release.tag_name || github.sha }}
       MICROPY_BOARD: ${{ matrix.board }}
       MICROPY_BOARD_VARIANT: ${{ matrix.variant }}
+      MICROPY_BOARD_DIR: "${{ github.workspace }}/src-${{ github.sha }}/${{ matrix.BOARD }}"
+      MICROPY_FROZEN_MANIFEST: "${{ github.workspace }}/src-${{ github.sha }}/modules/${{ matrix.modules }}.py"
       BOARD_NAME: ${{ matrix.name }}
       BUILD_TOOLS: src-${{ github.sha }}/ci/micropython.sh
 
@@ -81,12 +84,19 @@ jobs:
         source $BUILD_TOOLS
         micropython_clone
 
-    - name: "Py_Decl: Checkout py_decl"
+    - name: "Py_Decl: Checkout"
       uses: actions/checkout@v4
       with:
         repository: gadgetoid/py_decl
         ref: v0.0.2
         path: py_decl
+        
+    - name: "dir2uf2: Checkout"
+      uses: actions/checkout@v4
+      with:
+        repository: gadgetoid/dir2uf2
+        ref: v0.0.7
+        path: dir2uf2
 
     - name: "MicroPython: Build MPY Cross"
       run: |
@@ -111,6 +121,12 @@ jobs:
       run: |
         python3 py_decl/py_decl.py --to-json --verify build-${{ matrix.name }}/${{ env.RELEASE_FILE }}.uf2
 
+    - name: "dir2uf2: Append filesystem to UF2"
+      shell: bash
+      run: |
+        python3 -m pip install littlefs-python==0.12.0
+        ./dir2uf2/dir2uf2 --fs-compact --append-to build-${{ matrix.name }}/${{ env.RELEASE_FILE }}.uf2 --manifest ${{env.USER_FS_MANIFEST}} --filename with-filesystem.uf2 ${{env.USER_FS_SOURCE}}/
+
     - name: Store .uf2 as artifact
       uses: actions/upload-artifact@v4
       with:
diff --git a/README.md b/README.md
index 009bbe1..2a3808e 100644
--- a/README.md
+++ b/README.md
@@ -13,4 +13,7 @@ should automatically handle building MicroPython for you.
 * pga2350 - MicroPython and Pico SDK board definitions for PGA2350, with PSRAM variant
 * modules/c/example - An example MicroPython C++ module, demonstrating C class bindings
 * modules/py_frozen - Python files intended to be frozen into the firmware
-* modules/py_littlefs - Python files intended to be visible/editable in the LittleFS user filesystem
\ No newline at end of file
+* modules/py_littlefs - Python files intended to be visible/editable in the LittleFS user filesystem
+* modules/default.py - The MicroPython manifest file, for specifying frozen libs
+* modules/default.txt - The dir2uf2 LittleFS manifest file, for specifying included files
+* modules/default.cmake - The MicroPython USER_C_MODULES file, for specifying included C/C++ modules
\ No newline at end of file
diff --git a/ci/micropython.sh b/ci/micropython.sh
index 0a4b53a..2cbff92 100644
--- a/ci/micropython.sh
+++ b/ci/micropython.sh
@@ -52,6 +52,7 @@ function cmake_configure {
     -DMICROPY_BOARD_DIR=$MICROPY_BOARD_DIR \
     -DMICROPY_BOARD=$MICROPY_BOARD \
     -DMICROPY_BOARD_VARIANT=$MICROPY_BOARD_VARIANT \
+    -DMICROPY_FROZEN_MANIFEST=$MICROPY_FROZEN_MANIFEST \
     -DCMAKE_C_COMPILER_LAUNCHER=ccache \
     -DCMAKE_CXX_COMPILER_LAUNCHER=ccache
 }
diff --git a/modules/default.py b/modules/default.py
new file mode 100644
index 0000000..eef495b
--- /dev/null
+++ b/modules/default.py
@@ -0,0 +1,8 @@
+# Include the manifest.py from micropython/ports/rp2/boards/manifest.py
+include("$(PORT_DIR)/boards/manifest.py")
+
+# Include the manifest.py from micropython/<board>/manifest.py
+include("$(BOARD_DIR)/manifest.py")
+
+# Include pga/modules/py_frozen
+freeze("py_frozen/")
\ No newline at end of file
diff --git a/modules/default.txt b/modules/default.txt
new file mode 100644
index 0000000..8d75d26
--- /dev/null
+++ b/modules/default.txt
@@ -0,0 +1 @@
+example.py
\ No newline at end of file
diff --git a/modules/frozen.py b/modules/frozen.py
deleted file mode 100644
index e69de29..0000000
diff --git a/modules/littlefs.txt b/modules/littlefs.txt
deleted file mode 100644
index f2e897a..0000000
--- a/modules/littlefs.txt
+++ /dev/null
@@ -1 +0,0 @@
-lib/*/*.py
\ No newline at end of file
diff --git a/modules/py_frozen/frozen_example.py b/modules/py_frozen/frozen_example.py
new file mode 100644
index 0000000..e789599
--- /dev/null
+++ b/modules/py_frozen/frozen_example.py
@@ -0,0 +1,5 @@
+# This file should be frozen into the MicroPython build
+# try: `import frozen_example`
+
+def example():
+    print("Hello Frozen Example")
\ No newline at end of file
diff --git a/modules/py_littlefs/example.py b/modules/py_littlefs/example.py
new file mode 100644
index 0000000..51bd8e8
--- /dev/null
+++ b/modules/py_littlefs/example.py
@@ -0,0 +1,2 @@
+# This file should be added to the user-facing MicroPython filesystem
+print("Hello World")
\ No newline at end of file
diff --git a/pga2040/manifest.py b/pga2040/manifest.py
index 8505dcb..4819e73 100644
--- a/pga2040/manifest.py
+++ b/pga2040/manifest.py
@@ -1,5 +1 @@
-# Include the manifest.py from micropython/ports/rp2/boards/manifest.py
-include("$(PORT_DIR)/boards/manifest.py")
-
-# Include frozen.py from pga/modules/frozen.py
-include("../modules/frozen.py")
\ No newline at end of file
+# Board-specific frozen libs go here
\ No newline at end of file
diff --git a/pga2350/manifest.py b/pga2350/manifest.py
index 8505dcb..4819e73 100644
--- a/pga2350/manifest.py
+++ b/pga2350/manifest.py
@@ -1,5 +1 @@
-# Include the manifest.py from micropython/ports/rp2/boards/manifest.py
-include("$(PORT_DIR)/boards/manifest.py")
-
-# Include frozen.py from pga/modules/frozen.py
-include("../modules/frozen.py")
\ No newline at end of file
+# Board-specific frozen libs go here
\ No newline at end of file