Building EchoFox for multiple architectures

Our published images (ghcr.io/cosm1cbug/echofox, cosm1cbug/echofox) ship for linux/amd64 and linux/arm64 — covering x86 servers, Apple Silicon, AWS Graviton, and Raspberry Pi 4/5.

If you're building your own (forking, customising, or air-gapped), here's how.

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One-shot local build (single platform)

docker build -t echofox:local .

Builds for whatever architecture your machine is. Fine for docker run on the same host.

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Multi-arch build with buildx

Buildx ships with Docker Desktop and modern Docker Engine. On Linux it requires QEMU for cross-architecture emulation.

Setup (one-time)

# Install QEMU emulation
docker run --privileged --rm tonistiigi/binfmt --install all

# Create a buildx builder
docker buildx create --name echofox-builder --use --bootstrap

# Verify
docker buildx ls

Build and load locally (single arch — your host)

docker buildx build --load -t echofox:local .

Build and push (multi-arch)

docker buildx build \
  --platform linux/amd64,linux/arm64 \
  --tag ghcr.io/cosm1cbug/echofox:dev \
  --tag ghcr.io/cosm1cbug/echofox:latest \
  --push \
  .

You must be docker logined to GHCR first:

echo $GITHUB_TOKEN | docker login ghcr.io -u Cosm1cBug --password-stdin

Build and save to a tar (air-gapped)

docker buildx build \
  --platform linux/amd64,linux/arm64 \
  --output type=oci,dest=echofox-image.tar \
  .

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Pushing to Docker Hub and GHCR in one command

docker buildx build \
  --platform linux/amd64,linux/arm64 \
  --tag ghcr.io/cosm1cbug/echofox:v0.3.0-alpha \
  --tag ghcr.io/cosm1cbug/echofox:latest \
  --tag cosm1cbug/echofox:v0.3.0-alpha \
  --tag cosm1cbug/echofox:latest \
  --push \
  .

Make sure you've docker logined to both registries first.

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Verifying

docker buildx imagetools inspect ghcr.io/cosm1cbug/echofox:latest
# Should list manifests for linux/amd64 AND linux/arm64

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CI automation (M4)

The release workflow (coming in Milestone M4) will do all of this automatically on every tag push. For now it's a manual process.