Production-ready x402 payment protocol facilitator — verifies payment signatures and settles transactions on-chain over HTTP 402.
The facilitator is a trusted third party that acts on behalf of resource servers. It does not hold funds — it only validates payment payloads and broadcasts settlement transactions to the blockchain.
Built on r402, the modular Rust SDK for x402. See Security before using in production.
# Install from crates.io
cargo install facilitator
# Generate a commented config template
facilitator init
# Edit config.toml with your RPC URLs and signer keys, then start
facilitator serve# Using pre-built image
docker run -p 8080:8080 -v ./config.toml:/app/config.toml ghcr.io/qntx/facilitator
# Or build from source
docker build -t facilitator .
docker build -t facilitator --build-arg FEATURES=chain-eip155 . # EVM only
docker run -p 8080:8080 -v ./config.toml:/app/config.toml facilitator| Method | Path | Description |
|---|---|---|
GET |
/supported |
List supported payment kinds (version / scheme / network) |
POST |
/verify |
Verify a payment payload against requirements |
POST |
/settle |
Settle an accepted payment on-chain |
GET |
/health |
Health check |
facilitator <COMMAND>
Commands:
init Generate a default TOML configuration file
serve Start the facilitator HTTP server
Options:
-h, --help Print help
-V, --version Print version
facilitator init [OPTIONS]
Options:
-o, --output <PATH> Output path [default: config.toml]
--force Overwrite existing file
facilitator serve [OPTIONS]
Options:
-c, --config <PATH> Path to TOML config file [default: config.toml]
The server loads configuration from a TOML file (default: config.toml). Run facilitator init to generate a fully commented template.
host = "0.0.0.0"
port = 8080
# Global signers — shared across all chains of the same type.
# Env-var references ("$VAR" or "${VAR}") are resolved at startup.
[signers]
evm = ["$EVM_SIGNER_PRIVATE_KEY"] # hex, 0x-prefixed
solana = "$SOLANA_SIGNER_PRIVATE_KEY" # base58, 64-byte keypair
# EVM chains (CAIP-2 key format: "eip155:<chain_id>")
[chains."eip155:8453"]
rpc = [{ http = "https://mainnet.base.org" }]
[chains."eip155:84532"]
rpc = [{ http = "https://sepolia.base.org" }]
# Solana chains
[chains."solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp"]
rpc = "https://api.mainnet-beta.solana.com"
# Scheme registrations (optional — auto-generated from configured chains)
# [[schemes]]
# id = "v2-eip155-exact"
# chains = "eip155:{8453,84532}"| Variable | Default | Description |
|---|---|---|
HOST |
0.0.0.0 |
Bind address |
PORT |
8080 |
Listen port |
CONFIG |
config.toml |
Config file path (for serve) |
OTEL_* |
— | OpenTelemetry configuration |
| Family | Networks |
|---|---|
| EVM (EIP-155) | Ethereum, Base, Optimism, Arbitrum, Polygon, Avalanche, Celo, Monad, and testnets |
| Solana (SVM) | Mainnet, Devnet, and custom clusters |
| Feature | Default | Description |
|---|---|---|
chain-eip155 |
✓ | EVM chain support via r402-evm |
chain-solana |
✓ | Solana chain support via r402-svm |
telemetry |
✓ | OpenTelemetry tracing and metrics |
Disable unused chains to reduce binary size and compile time:
cargo install facilitator --no-default-features --features chain-eip155See SECURITY.md for disclaimers, supported versions, and vulnerability reporting.
- r402 — modular Rust SDK for the x402 payment protocol
- x402 Protocol Specification — protocol design by Coinbase
- coinbase/x402 — official reference implementations (TypeScript, Python, Go)
Licensed under either of:
- Apache License, Version 2.0 (LICENSE-APACHE or https://www.apache.org/licenses/LICENSE-2.0)
- MIT License (LICENSE-MIT or https://opensource.org/licenses/MIT)
at your option.
Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in this project shall be dual-licensed as above, without any additional terms or conditions.
