feat: add Linux arm64 AppImage support for SBC users (Pi, Orange Pi, etc.)

[toastmanAu]

Add Linux arm64 (aarch64) AppImage support

Summary

This PR adds support for building Neuron as a Linux arm64 AppImage, targeting Raspberry Pi 4/5, Orange Pi, ROCK series boards and other aarch64 single-board computers running Linux — which are popular in the CKB node-running community.

A working Neuron-v0.204.0-arm64.AppImage (192 MB, verified ELF aarch64) was built successfully on an Orange Pi 5 (aarch64, Ubuntu 22.04) using the changes in this PR.

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Changes

1. scripts/download-ckb.sh — add download_linux_aarch64()

Added a new function that downloads the aarch64-unknown-linux-gnu CKB binary (which already exists in every CKB release) and saves it as bin/linux/ckb-arm64:

function download_linux_aarch64() {
  CKB_FILENAME="ckb_${CKB_VERSION}_aarch64-unknown-linux-gnu"
  cd $ROOT_DIR/packages/neuron-wallet/bin/linux
  curl -O -L "${GITHUB_RELEASE_URL}/${CKB_VERSION}/${CKB_FILENAME}.tar.gz"
  tar xvzf ${CKB_FILENAME}.tar.gz
  cp ${CKB_FILENAME}/ckb ./ckb-arm64
  rm -rf $CKB_FILENAME ${CKB_FILENAME}.tar.gz
}

Also added a linux-arm64 case to the switch:

linux-arm64) download_linux_aarch64; download_linux_light;;

Note on ckb-light-client: No arm64 Linux release exists in the ckb-light-client repo yet. The x86_64 binary is currently used for both architectures. A separate issue/PR to the ckb-light-client repo would complete that gap.

2. packages/neuron-wallet/electron-builder.yml — add arm64 target + extraFile

linux:
  extraFiles:
    - from: "bin/linux/ckb"
      to: "bin/ckb"
    - from: "bin/linux/ckb-arm64"   # ← new
      to: "bin/ckb-arm64"
    # ... rest unchanged
  target:
    - target: AppImage
      arch:
        - x64
        - arm64    # ← new

3. package.yml (GitHub Actions) — add arm64 Linux runner

To build the arm64 AppImage in CI, add an ubuntu-24.04-arm runner to the matrix:

jobs:
  default:
    strategy:
      matrix:
        node: [22]
        os:
          - macos-latest
          - ubuntu-latest
          - ubuntu-24.04-arm   # ← new: GitHub's hosted arm64 runner
          - windows-latest

And add a conditional upload step:

- name: Upload Neuron Linux arm64
  if: runner.os == 'Linux' && runner.arch == 'ARM64'
  uses: actions/upload-artifact@v4
  with:
    name: Neuron-Linux-arm64
    path: release/Neuron-*-arm64.AppImage

---

Build instructions (manual, on arm64 Linux)

# Prerequisites
sudo apt-get install -y libudev-dev libusb-1.0-0-dev fuse libfuse2 rpm python3-setuptools

# Clone and install
git clone https://github.com/nervosnetwork/neuron.git
cd neuron
yarn global add lerna
CI=false yarn
yarn build
./scripts/copy-ui-files.sh

# Download CKB binaries (both x64 and arm64)
./scripts/download-ckb.sh linux

# Build AppImage for arm64
cd packages/neuron-wallet
npx electron-builder --linux --arm64 --config.npmRebuild=false

Output: release/Neuron-v{version}-arm64.AppImage

Flags explained:

• --linux --arm64: target platform and architecture
• --config.npmRebuild=false: skip native module rebuild (avoids cross-compilation issues when building arm64 on an arm64 host where modules are already built for the right arch)

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Tested on

Device	OS	Result
Orange Pi 5 (RK3588S)	Ubuntu 22.04 arm64	✅ Neuron-v0.204.0-arm64.AppImage built, 192 MB

The resulting AppImage is a valid ELF aarch64 executable:

ELF 64-bit LSB executable, ARM aarch64, version 1 (SYSV), dynamically linked,
interpreter /lib/ld-linux-aarch64.so.1, for GNU/Linux 3.7.0, stripped

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Why this matters

Single-board computers (Raspberry Pi 4/5, Orange Pi, Rock Pi, etc.) are widely used to run CKB full nodes — they're low-power, always-on, and affordable. Many CKB community members running nodes on these devices also want to use Neuron as their wallet but currently have no official binary. An arm64 AppImage closes that gap with a single self-contained download.

[toastmanAu]

Testing Results — Tested on arm64 hardware

Orange Pi 5 (RK3588, aarch64) — Ubuntu 22.04

✅ AppImage launches and renders correctly

Screenshot of welcome screen (running on Pi 5):

Full UI renders, wallet import/create options visible, app functional

Log output confirms:

• App starts successfully
• Connects to local CKB node (http://127.0.0.1:8114)
• Mainnet genesis hash verified
• ckb-arm64 bundled binary is genuine aarch64 ELF ✅

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Known Issues / Notes

1. Auto-updater 404 (expected)

Error: Cannot find latest-linux-arm64.yml in the latest release artifacts

The updater looks for latest-linux-arm64.yml on the official GitHub release. This will 404 until this PR is merged and a new release is cut. Not a blocker — expected behaviour for a draft PR.

2. libz.so missing on minimal systems
The AppImage runtime requires the unversioned libz.so symlink. On some minimal arm64 systems it may only have libz.so.1. Fix:

sudo apt install zlib1g-dev

Or: sudo ln -sf /lib/aarch64-linux-gnu/libz.so.1 /lib/aarch64-linux-gnu/libz.so

3. GPU / SwiftShader fallback
On BSP 5.10 kernels (Rockchip SBCs), libGL: failed to load driver: rockchip causes the GPU process to fail and Electron falls back to software rendering (SwiftShader). The app still works correctly — just falls back to CPU rendering. This is a BSP driver limitation, not an Electron or Neuron issue. On mainline kernels with Panfrost or Mesa this is not an issue.

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Tested build: Neuron-v0.204.0-arm64.AppImage (192MB, ELF aarch64, built on Orange Pi 5)