// Deploy and configure AlephOS on flight computers, write flight software services, and manage NixOS modules for the Aleph platform. Use when working with aleph/, deploying to Jetson Orin hardware, writing NixOS modules, flashing firmware, or composing a flight software stack.
Develop and contribute to the Elodin codebase. Use when building Elodin from source, running tests, modifying core libraries, working on the Rust workspace, or onboarding as a contributor.
Contribute to the Elodin Editor, the 3D viewer and graphing tool. Use when editing files in libs/elodin-editor/ or apps/elodin/, working on the Bevy/Egui UI, modifying viewport rendering, telemetry graphs, video streaming, KDL schematics, or the command palette.
Tips for working with a Bevy application
Work with the Cranelift JIT MLIR backend. Use when modifying libs/cranelift-mlir/, adding new StableHLO ops, debugging simulation correctness issues, running the checkpoint diagnostic tool, or working on the pointer-ABI tensor runtime.
Create and modify physics simulations using the Elodin Python SDK. Use when writing or editing simulation Python files, defining components or systems, spawning entities, configuring 6DOF physics, setting up visualization, or integrating with SITL/HITL workflows.
Profile Elodin with Tracy. Use when profiling the editor, simulation, building with tracy features, capturing traces, analyzing performance, or adding custom instrumentation.
| name | elodin-aleph |
| description | Deploy and configure AlephOS on flight computers, write flight software services, and manage NixOS modules for the Aleph platform. Use when working with aleph/, deploying to Jetson Orin hardware, writing NixOS modules, flashing firmware, or composing a flight software stack. |
Aleph is an NVIDIA Jetson Orin-based flight computer running NixOS. The aleph/ directory contains NixOS modules, packages, and deployment tooling for composing a Linux flight software stack.
# SSH into Aleph (USB-C rightmost port)
ssh root@fde1:2240:a1ef::1 # Default password: root
# SSH over WiFi (after setup)
ssh aleph-99a2.local # Hostname shown by `hostname` command
# Deploy configuration changes
./deploy.sh # Default: $USER@fde1:2240:a1ef::1
./deploy.sh root@aleph-99a2.local # Custom SSH target
# Build SD image for fresh install
nix build --accept-flake-config .#packages.aarch64-linux.sdimage
ssh root@fde1:2240:a1ef::1 (password: root)aleph-setup wizard (or run it manually)iwctl station wlan0 connect "NetworkName"ping google.comAfter WiFi setup, SSH directly via aleph-XXXX.local.
The recommended cycle for iterating on the NixOS configuration:
aleph/flake.nix, aleph/modules/, or aleph/kernel/./deploy.sh from the aleph/ directoryConfiguration is in aleph/flake.nix, composed from modules in aleph/modules/:
| Module | Purpose |
|---|---|
hardware.nix | Forked kernel, device tree for Orin |
fs.nix | SD-card image compatibility |
usb-eth.nix | USB Ethernet gadget (IPv6 fde1:2240:a1ef::1) |
wifi.nix | WiFi via iwd |
minimal.nix | Minimal NixOS profile |
aleph-base.nix | Base configuration |
aleph-dev.nix | Dev packages (CUDA, OpenCV, git) |
| Module | Purpose |
|---|---|
c-blinky.nix | STM32 firmware flash-on-deploy + serial-bridge ordering |
elodin-db.nix | Elodin-DB telemetry database service |
aleph-serial-bridge.nix | Sensor data from serial → Elodin-DB |
mekf.nix | MEKF attitude estimation service |
msp-osd.nix | MSP DisplayPort OSD for FPV goggles |
udp-component-broadcast.nix | UDP component broadcasting |
udp-component-receive.nix | UDP component receiving |
elodinsink.nix | GStreamer plugin for video → Elodin-DB |
tegrastats-bridge.nix | Orin SoC telemetry bridge |
| Module | Purpose |
|---|---|
aleph-setup.nix | First-time setup wizard |
installer.nix | USB installer system |
aleph/template/flake.nix is the starting point for user configurations. It imports Aleph modules and configures services:
# Key structure in template/flake.nix
{
inputs.elodin.url = "github:elodin-sys/elodin";
outputs = { self, elodin, nixpkgs }: {
nixosConfigurations.aleph = nixpkgs.lib.nixosSystem {
modules = [
elodin.nixosModules.aleph-base
elodin.nixosModules.elodin-db
elodin.nixosModules.mekf
# ... other modules
];
};
};
}
These Rust applications in fsw/ run as NixOS services on Aleph:
| Application | Path | Purpose |
|---|---|---|
c-blinky | fsw/c-blinky/ | STM32H747 bare-metal LED blink + UART COBS logging |
sensor-fw | fsw/sensor-fw/ | STM32H747 firmware: IMU, mag, baro → USB/UART |
serial-bridge | fsw/serial-bridge/ | Serial port → Elodin-DB (parses EL COBS frames) |
mekf | fsw/mekf/ | Sensor fusion for attitude estimation |
msp-osd | fsw/msp-osd/ | OSD telemetry display for FPV |
gstreamer | fsw/gstreamer/ | H.264 video → Elodin-DB (elodinsink) |
video-streamer | fsw/video-streamer/ | Video files → AV1 → Elodin-DB |
udp_component_broadcast | fsw/udp_component_broadcast/ | Real-time UDP component sharing |
aleph-status | fsw/aleph-status/ | System status display |
aleph-setup | fsw/aleph-setup/ | Interactive first-time setup |
blackbox | fsw/blackbox/ | Blackbox data processing |
lqr | fsw/lqr/ | LQR control system |
For unbootable or corrupted systems:
nix build --accept-flake-config .#packages.aarch64-linux.sdimagesudo dd if=aleph-os.img of=/dev/sdX bs=4M status=progress oflag=syncssh root@fde1:2240:a1ef::1aleph-installer# Reset the STM32 MCU
reset-mcu --app # Boot application firmware
reset-mcu --bootloader # Enter ROM bootloader (BOOT0 high + NRST pulse)
reset-mcu --nrst-low # Hold NRST low
reset-mcu --nrst-high # Release NRST high
reset-mcu --boot0-high # Hold BOOT0 high
# Flash firmware (default: UART via stm32flash)
flash-mcu --bin firmware.bin # Flash binary to 0x08000000
flash-mcu --elf firmware.elf # Flash ELF (objcopy to bin first)
# Override method: ALEPH_FLASH_MCU_METHOD=swd flash-mcu --elf firmware.elf
The STM32 is flashed from the Orin via the ROM UART bootloader using stm32flash at 19200 8E1 on /dev/ttyTHS1. The NixOS service c-blinky-flash handles this automatically during deploy.sh.
Critical timing requirement: The STM32H747 ROM bootloader has a narrow interface detection window (~100ms) after NRST release. The stm32flash 0x7F sync byte must arrive during this window. If missed, the ROM falls to a dual-core sync handler and hangs forever. The flash-mcu.sh UART path handles this with tight timing: NRST low -> BOOT0 high -> NRST release -> 100ms -> stm32flash.
Tegra UART quirk: stm32flash cannot set termios flags on ttyTHS* devices. The script pre-configures the port with stty before calling stm32flash.
GPIO mapping (open-source expansion board):
fsw/c-blinky/main.c is bare-metal C for the STM32H747 CM7 core. Runs on HSI at 64MHz (no PLL). Outputs COBS-encoded EL log frames on USART1 PA9 (TX) at 115200 8N1. The serial-bridge service parses these frames and forwards them to elodin-db as aleph.stm32.log.
EL frame wire format: 0x00 | COBS(['E','L', ver=1, kind=1, level, ...msg...]) | 0x00
Built by Nix (aleph/pkgs/c-blinky.nix) using arm-none-eabi-gcc. Produces firmware.elf and firmware.bin.
The elodin-db.nix module defaults to dbUniqueOnBoot = true, creating a fresh timestamped elodin-db instance on each deploy/boot at /db/default-YYYYMMDD-HHMMSS on port 2240. The elodin-db-default oneshot manages the lifecycle: it stops any old elodin-db@* template instances and waits for port 2240 to be free before starting the new one. The template service has stopIfChanged = false; restartIfChanged = false so NixOS activation never races with it. Set dbUniqueOnBoot = false for a single persistent /db/default instance.
Connect from a development machine: elodin editor <aleph-ip>:2240