A Rust-based backend service that provides zero-knowledge proof (ZKP) verification for Sudoku puzzles using the SP1 ZK-VM framework. This system allows users to submit Sudoku puzzles and their solutions, then generates cryptographic proofs that verify the solution is correct without revealing the solution itself.
- Sudoku Verification: Verifies that Sudoku solutions are valid according to standard rules
- Zero-Knowledge Proofs: Generates cryptographic proofs using SP1 framework
- Asynchronous Job Processing: Handles proof generation as asynchronous jobs
- WebSocket Support: Provides real-time updates on job status and logs
- RESTful API: Clean API for submitting puzzles and retrieving proof status
- Rust: The entire backend is written in Rust, leveraging its safety and performance features
- Axum Framework: Modern, ergonomic web framework for building HTTP and WebSocket servers
- Tokio: Asynchronous runtime for handling concurrent operations
- SP1 ZK-VM: Zero-knowledge virtual machine framework by Succinct Labs
- Serde: For serialization and deserialization of JSON data
SudokuBoard: Represents a Sudoku puzzle with a 9x9 gridSudokuSolution: Represents a solution to a Sudoku puzzleProofInput: Contains both the initial board and solutionProofResponse: Contains the generated proof and public valuesJobResponse: Represents the status and result of a proof generation job
The main server is implemented in src/main.rs and provides:
- HTTP endpoints for submitting puzzles and checking proof status
- WebSocket connections for real-time updates
- Middleware for logging and CORS
- Job storage and processing management
The SP1 prover (sp1_prover/src/main.rs) implements:
- Verification logic that runs inside the SP1 ZK-VM
- Sudoku solution validation according to standard rules
- Cryptographic proof generation
Core verification functions in src/lib.rs:
is_valid_sudoku: Checks if a Sudoku board follows the rulesverify_solution: Verifies that a solution is valid and matches the initial board
-
POST /api/prove: Submit a Sudoku puzzle and solution for verification{ "board": [[0,0,0,0,0,0,0,0,0], ...], "solution": [[1,2,3,4,5,6,7,8,9], ...] } -
GET /api/status/:job_id: Check the status of a proof generation job{ "job_id": "123e4567-e89b-12d3-a456-426614174000", "status": "Complete", "result": { "public_values": "...", "proof": "..." }, "error": null }
GET /api/ws/proof/:job_id: WebSocket connection for real-time proof updatesGET /api/ws/logs/:job_id: WebSocket connection for real-time log updates
The system uses SP1, a zero-knowledge virtual machine framework, to generate proofs that:
-
The solution follows all Sudoku rules:
- No repeating numbers in any row
- No repeating numbers in any column
- No repeating numbers in any 3x3 box
- All numbers are between 1-9
-
The solution matches the initial puzzle (all pre-filled numbers remain unchanged)
The proof can be verified without revealing the actual solution, providing privacy while ensuring correctness.
- Rust (latest stable version)
- Cargo
- SP1 SDK
# Clone the repository
git clone https://github.com/yourusername/succinct_sudoku_backend.git
cd succinct_sudoku_backend
# Build the project
cargo build --release
# Run the server
cargo run --release- Build without including ELF binary:
cargo build --release --features no_elf
The project includes configuration for multiple deployment platforms:
- Heroku/Dokku: Uses the included
Procfile - Railway: Configuration in
railway.toml - Custom Deployment: Nixpacks configuration in
nixpacks.toml
# Run tests
cargo test
# Run specific test
cargo test verify_solutionThe system manages proof generation jobs using:
- A shared
HashMapprotected by aMutexto store job statuses - Unique job IDs generated using UUID
- Job status tracking (Processing, Complete, Failed)
Proof generation is handled asynchronously:
- Jobs are submitted and processed in the background
- Clients can check status or subscribe to WebSocket updates
- The system can handle multiple proof generation jobs concurrently
Comprehensive logging is implemented with:
- Request/response logging
- Job status updates
- Proof generation progress
- Error tracking
This project is licensed under the terms specified in the LICENSE file.