Install the Sombra prover

The Sombra extension ships proofs to a server-side GPU prover by default. If you want proofs to generate on your own machine — for the strongest privacy guarantee — install the Sombra prover locally.

Requirements

• Google Chrome with the Sombra extension installed. The Sombra extension is published only to the Chrome Web Store; other browsers (Firefox, Safari, Edge) are not supported in the MVP.
• Linux (x86_64) OR macOS (Apple Silicon — M1/M2/M3/M4). Windows builds land later.

Download

Pick the build that matches your machine.

Optional: verify the download

Each tarball ships with a SHA-256 checksum file you can use to confirm the download wasn't corrupted in transit. Run the verify command from the same directory you saved the tarball to:

# Linux
curl -O https://docs.sombra.tech/downloads/sombra-prover-linux-x64.tar.gz.sha256
sha256sum -c sombra-prover-linux-x64.tar.gz.sha256

# macOS
curl -O https://docs.sombra.tech/downloads/sombra-prover-macos-arm64.tar.gz.sha256
shasum -a 256 -c sombra-prover-macos-arm64.tar.gz.sha256

Either should print <filename>: OK. If it doesn't, re-download — don't proceed to install.

After downloading

1. Extract the archive

# Linux:
tar -xzf sombra-prover-linux-x64.tar.gz

# macOS:
tar -xzf sombra-prover-macos-arm64.tar.gz

This unpacks a single folder (e.g. sombra-prover-linux-x64-v0.1.0/) containing the daemon binary, an install.sh helper, a README.md with platform-specific notes, the template files the installer uses (manifest.json.template, daemon_wrapper.sh.template), and a VERSION file you can use to confirm which release you have.

2. Run the installer

The installer is self-contained — run it straight from the extracted folder. No need to cd in first:

# Linux:
./sombra-prover-linux-x64-*/install.sh

# macOS:
./sombra-prover-macos-arm64-*/install.sh

The installer copies the binary to ~/.local/share/sombra/, registers the native-messaging manifest with Chrome, and prints a confirmation when it's done. No sudo required.

3. Restart Chrome

Fully quit Chrome and relaunch. Chrome only picks up new native-messaging hosts on cold start — closing the window is not enough.

4. Switch the extension to local proving

Open the Sombra extension, go to Settings → Prover mode, and choose Local.

You should see a Daemon connected indicator within a few seconds. The next transfer you start will prove on your machine.

Verify it's working

Start a transfer. The first proof after a fresh install takes 30–60 seconds longer than steady state while the zkVM image compiles and caches — subsequent proofs are faster.

Updating

A new release means a new download from this page. Re-run install.sh from the new archive — it overwrites the existing binary in place. No re-registration needed.

Switching back to server proving

In the extension, go to Settings → Prover mode and choose Server. The extension stops talking to the local prover; nothing else changes.

Uninstall

Run the installer with --uninstall from the extracted archive:

# Linux:
./sombra-prover-linux-x64-*/install.sh --uninstall

# macOS:
./sombra-prover-macos-arm64-*/install.sh --uninstall

This removes the binary, the native-messaging manifest, and any cached proof artifacts. Your wallet keys live in the extension and are untouched.

What the prover does

• Runs entirely on your machine.
• Accepts witness data from the extension over Chrome's Native Messaging channel (a stdio pipe — no network).
• Generates a STARK proof and returns it to the extension.
• Has no telemetry and makes no outbound network calls.

Related

• Architecture — where the prover sits in the full pipeline.
• Security — what proving locally changes for your threat model.