| title | Building from Source |
|---|
The custom firmware uses an overlay system to modify the base Snapmaker firmware. Overlays are modular modifications that:
- Add patches to modify existing firmware files
- Copy additional files to the firmware root filesystem
- Run build-time scripts to install components
- Enable features without changing the base firmware source
Each overlay is self-contained and numbered to control application order. This modular approach makes it easy to:
- Enable/disable features by including/excluding overlays
- Add custom modifications without conflicts
For external third-party components, see Third-Party Integrations.
For external RFID API and mapping details, see External RFID Support.
- Docker installed on your system
The ./dev.sh script automatically sets up a Debian Trixie ARM64 environment with all required dependencies.
The project is hosted on GitHub with a mirror on Codeberg:
- GitHub: https://github.com/paxx12
- Codeberg: https://codeberg.org/paxx12-snapmaker-u1
To use Codeberg as the source instead of GitHub, configure git to automatically remap GitHub URLs:
git config --global url."https://codeberg.org/paxx12-snapmaker-u1/".insteadOf "https://github.com/paxx12/"This remaps all GitHub repository URLs to Codeberg automatically, including submodules and dependencies.
Build tools and download firmware:
./dev.sh make tools
./dev.sh make firmwareBuild extended firmware:
./dev.sh make build PROFILE=extended OUTPUT_FILE=firmware/U1_extended.binOpen a shell in the development environment:
./dev.sh bashThe PROFILE argument is parsed as <firmware>[-<mod>]*: a single required
firmware name, followed by zero or more optional mod names, each joined
with a -. The firmware name selects overlays from overlays/firmware-<firmware>/,
and each mod name adds overlays from overlays/mods/<mod>/. Mods
can be freely combined, e.g. extended-devel, extended-qemu, or
extended-devel-qemu.
Run make mods to list the firmwares and mods currently available.
See Mods for naming conventions and the rules around contributing your own mod.
Overlays are organized into categories based on their scope and build mods. Each overlay is numbered to indicate its application order within its category.
- common/ - Core modifications applied to all firmware builds
- firmware-<name>/ - Modifications specific to a firmware, e.g.
firmware-extended/ - mods/<name>/ - Optional, composable overlays enabled by adding
-<name>toPROFILE, e.g.mods/devel/
extended-devel- Add thedevelmod overlays fromoverlays/mods/devel/- e.g.
./dev.sh make build PROFILE=extended-devel
- e.g.
extended-qemu- Add theqemumod overlays fromoverlays/mods/qemu/(eth0 hotplug and virtio-touch hwdb mapping for the QEMU dev environment)- e.g.
./dev.sh make build PROFILE=extended-qemu
- e.g.
extended-afc- Experimental. Add theafcmod overlays fromoverlays/mods/afc/, integrating the full AFC-Klipper-Add-On for physical AFC hardware (hubs, buffers, lane control) over CAN bus. See Experimental AFC Mod below.- e.g.
./dev.sh make build PROFILE=extended-afc
- e.g.
When running firmware built with the devel mod, additional development tools are available:
Entware Package Manager
The Entware is considered highly untrusted component, and might be removed at any point in the future without notice.
The devel mod includes Entware support for installing additional packages. After booting the devel firmware, initialize Entware:
entware-ctrl initThis sets up the Entware environment in /userdata/extended/entware and installs the bootstrap packages.
Other entware-ctrl commands:
entware-ctrl start- Activate Entware (mount /opt)entware-ctrl stop- Deactivate Entware (unmount /opt)entware-ctrl nuke- Remove Entware installation completely
Once initialized, use opkg to install packages from the Entware repository.
Experimental: The
afcmod is not maintained by this project (see Mods) and may break or be removed at any point without notice. It does not ship in public releases — it is only available as adevelop-channel CI build artifact or via a local build from source.
Unlike the AFC-Lite Stub, which is a status-reporting-only
compatibility shim included in the regular extended build, the afc mod
adds the real AFC-Klipper-Add-On
for people with actual AFC hardware (hubs, buffers, lane control) connected
over CAN bus. It:
- Clones
AFC-Klipper-Add-Onfrom upstream at build time into/home/lava/AFC-Klipper-Add-On. - Adds udev rules bringing up the onboard CAN bus chip at 1 Mbps so external
AFC MCUs can be reached — see
overlays/mods/afc/docs/canbus.mdfor wiring and MCU flashing instructions. - Patches Moonraker's gcode metadata parser and Klipper's extruder handling for compatibility with AFC's virtual lane extruders.
- Exposes an Enable AFC-Klipper-Add-On Plugin toggle under
Snapmaker Components in Fluidd/Mainsail firmware config, which runs
AFC-Klipper-Add-On's own installer to wire it into Klipper. It is disabled
by default even on
extended-afcbuilds.
├── common/ Core overlays applied to all builds
├── firmware-${firmware}/ Firmware-specific overlays
└── mods/${mod}/ Optional overlays enabled by `-${mod}` in PROFILE
Each overlay directory can contain:
patches/- Patch files applied to extracted firmwareroot/- Files copied to firmware root filesystemscripts/- Build-time scripts executed during firmware buildpre-scripts/- Scripts executed before main build process
Overlays are applied in the following order:
- All overlays from
common/(in numeric order) - Firmware-specific overlays from
firmware-${firmware}/(in numeric order) - Mod-specific overlays from
mods/${mod}/(in numeric order), for each-${mod}inPROFILE, in the order given
The 20-klipper-patches overlay in firmware-extended/ backports upstream Klipper commits. To add new patches:
-
Download the commit as a patch from GitHub:
wget https://github.com/Klipper3d/klipper/commit/16fc46fe5.patch -O 01_16fc46fe5.patch
GitHub serves any commit as a patch by appending
.patchto the commit URL. -
Name with order prefix and commit hash:
01_16fc46fe5.patch 02_6d1256ddc.patch 03_16b4b6b30.patch -
Place in the target path within the overlay:
overlays/firmware-extended/20-klipper-patches/patches/home/lava/klipper/The
patches/directory maps to the firmware root, sopatches/home/lava/klipper/applies patches to/home/lava/klipper/where Klipper is installed. -
Edit the patch to remove irrelevant hunks: Upstream commits often include
docs/and config changes that don't apply. Remove those hunks, keeping only the Python code changes inklippy/. -
Document in the overlay README: Update
20-klipper-patches/README.mdwith links to the upstream commits.
.
├── .github/ Automated release builds
├── overlays/ Overlay directories
│ ├── common/ Core overlays for all builds
│ ├── firmware-${firmware}/ Firmware-specific overlays
│ └── mods/${mod}/ Optional overlays enabled by `-${mod}` in PROFILE
├── firmware/ Downloaded and generated firmware files
├── scripts/ Build and modification scripts
├── tmp/ Temporary build artifacts
├── tools/ Firmware manipulation tools
│ ├── rk2918_tools/ Rockchip image tools
│ └── upfile/ Firmware unpacking tool
├── Makefile Build configuration
└── vars.mk Firmware version and kernel configuration
Edit vars.mk to configure base firmware and kernel.
To extract and examine the base firmware:
./dev.sh make extractOutput: tmp/extracted-<version>/ (the FIRMWARE_VERSION from vars.mk)
To build and deploy firmware directly to a connected printer:
./dev.sh ./scripts/dev/upgrade-firmware.sh root@<printer-ip> <profile>Example:
./dev.sh ./scripts/dev/upgrade-firmware.sh root@192.168.1.100 extendedBy default, the script uses snapmaker as the SSH password. To use a different password:
PASSWORD=mypassword ./dev.sh ./scripts/dev/upgrade-firmware.sh root@192.168.1.100 extendedThe project uses GitHub Actions for automated releases:
- Changes pushed to
maintrigger a pre-release build - Extended firmware is built
- Version is auto-incremented using
scripts/next_version.sh - Release artifacts are published to GitHub Releases
afptool- Android firmware package toolimg_maker- Create Rockchip imagesimg_unpack- Unpack Rockchip imagesmkkrnlimg- Create kernel images
Firmware unpacking utility for Snapmaker update files.