OpenVM v2 Wasm Stark Verifier

WebAssembly bindings for the OpenVM v2 STARK verifier.

Overview

This module builds the verify_vm_stark_proof_decoded function from the OpenVM v2 openvm-verify-stark-host library into WebAssembly, enabling STARK proof verification to run directly in both web browsers and Node.js environments.

This is the v2 counterpart of openvm-wasm-stark-verifier, updated to work with the OpenVM v2 proof format from openvm-eth/bin/reth-verify.

Upstream revisions

We build from the same commits as openvm-eth develop-v2.1.0, pinned in the committed Cargo.lock:

Crate source	Reference	Revision
openvm-org/openvm	tag v2.x.0-preview.2	16c26a32
openvm-org/stark-backend	branch main	362c7ad8

To update, read openvm-eth's own Cargo.lock and match both pins.

patches/ holds two vendored crates, applied via [patch] in Cargo.toml. OpenVM's rv64 migration made openvm-circuit assume a 64-bit host, which does not compile for wasm32-unknown-unknown. reth-verify is a native binary, so it never hits this. Both patches touch only code the verifier never executes:

• openvm-platform — MEM_SIZE = 1 << MEM_BITS overflows a 32-bit usize now that MEM_BITS is 32. Saturates on 32-bit targets; 64-bit builds are unchanged.
• rvr-state — the PreflightTranscriptState FFI layout assertions hard-code 8-byte pointers. Gated on target_pointer_width = "64" rather than weakened.

Delete patches/ and the [patch] section once upstream builds for 32-bit targets.

Usage

Installation

npm install @ethproofs/openvm2-wasm-stark-verifier

React Integration

import init, {
  main,
  verify_stark,
} from '@ethproofs/openvm2-wasm-stark-verifier';

await init(); // Initialize WASM (if needed)
main(); // Initialize panic hook

// Verify a proof (supports both raw and zstd-compressed proofs)
const isValid = verify_stark(proofBytes, vkBytes);

Node.js Usage

const { main, verify_stark } = require('@ethproofs/openvm2-wasm-stark-verifier');

// The Node.js version initializes automatically

main(); // Initialize panic hook
const result = verify_stark(proofBytes, vkBytes);

Proof Format

• Proof bytes: A VmStarkProof encoded with the OpenVM stark-backend codec (VmStarkProof::decode_from_bytes), optionally zstd-compressed

• VK bytes: Serialized VmStarkVerifyingKey, in either encoding:

  • bincode 1.x — written by axiom-edge's generate_edge_vm_vk, and the format of every VK generated since that switch. Note 1.x, not 2.x; the wire formats are not interchangeable.
  • bitcode — written by openvm's write_vk_to_file, and the format of older VKs.

  Neither encoding is self-describing, so verify_stark tries bincode first and falls back to bitcode. This mirrors load_vm_vk in reth-verify.

This matches the proof format produced by the openvm-eth reth-benchmark tooling.

Proofs and verifying keys are circuit-specific: a proof only verifies against the VK for the exact circuit that produced it. The current reth.vm.vk is a different shape from earlier v2 VKs, so regenerate proofs and VKs as a pair when upstream updates.

Testing

Installation

npm install

Prerequisites

• Rust
• wasm-pack

Building

# Build for all targets
npm run build:all

Node.js Example

npm run test:node

This runs the Node.js example that loads proof and verification key files from the filesystem and verifies them.

Browser Example

npm run test

This starts a local HTTP server at http://localhost:8080 with a browser example that demonstrates:

• Loading the WASM module in a browser environment
• File upload interface for proof and verification key files
• Interactive STARK proof verification
• Performance metrics and detailed logging
• Error handling and user feedback

Note: The browser example requires files to be served over HTTP due to WASM CORS restrictions. The included server script handles this automatically.