x402 Facilitator — Deploy

x402 payment facilitator for on-chain verification and settlement. Handles EVM and Solana chains with automatic HTTPS, rate limiting, and zero-downtime updates.

Architecture

flowchart LR
    A[Client]
    B["Caddy (TLS + rate limit)
:80 / :443"]
    C["Facilitator
:8080"]

    A <-- HTTPS --> B
    B <-- HTTP --> C

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• Caddy — Auto-HTTPS, rate limiting, security headers, request filtering
• Facilitator — x402 payment verification, settlement, signer key management
• Watchtower — Auto-pulls new images every 5 min, rolling restarts

Prerequisites

• Linux server (Ubuntu 22.04+ / Debian 12+)
• Domain with DNS A record → server IP
• Ports 80 and 443 open

Quick Start

git clone https://github.com/qntx/facilitator-deploy.git
cd facilitator-deploy

# 1. Configure — edit these two files:
cp config.example.toml config.toml
nano config.toml    # Add EVM / Solana signer private keys
nano Caddyfile      # Set your domain (replace facilitator.qntx.fun)

# 2. Deploy — one command does everything:
sudo bash setup.sh

# 3. Verify:
curl https://YOUR_DOMAIN/health
curl https://YOUR_DOMAIN/supported

The setup script is idempotent — safe to re-run after failures. It resumes from where it stopped.

sudo bash setup.sh --check    # Pre-flight checks only (no changes)
sudo bash setup.sh --force    # Redo all steps from scratch

Daily Operations

After setup, use fctl (installed to PATH) or make shortcuts:

Lifecycle

Command	make	Description
fctl deploy	make deploy	Pull latest images + recreate containers + health check
fctl reload	make reload	Smart reload — auto-detects which config changed
fctl update	make update	Pull latest Docker images + rolling restart

Observability

Command	make	Description
fctl status	make status	Dashboard: service status, health, image versions
fctl doctor	make doctor	Full diagnostics (ports, DNS, TLS, disk, health)
fctl logs	make logs	Follow facilitator logs
fctl logs caddy	make logs-caddy	Follow Caddy logs
fctl logs watchtower	make logs-watchtower	Follow Watchtower logs
fctl logs all	make logs-all	Follow all service logs

Configuration

Command	make	Description
fctl edit config	make edit-config	Auto-backup → edit → smart reload
fctl edit caddy	make edit-caddy	Auto-backup → edit → smart reload
fctl backup	make backup	Backup all config files (keeps last 10)
fctl restore <ts>	—	Restore config from backup timestamp

Maintenance

Command	make	Description
fctl reset	make reset	Stop all + remove volumes (destructive, requires confirmation)
fctl purge	make purge	Force-remove ALL x402-* containers/volumes/networks
—	make prune	Remove dangling Docker images

Common Workflows

Config changed → reload

nano config.toml           # Make changes
fctl reload                # Auto-detects config.toml changed → restarts only facilitator

Update Docker images manually

fctl update                # Pulls latest facilitator → rolling restart → health check

Watchtower also auto-updates every 5 minutes. Manual update is only needed for immediate updates.

Something broken → diagnose

fctl doctor                # Checks: Docker, disk, ports, containers, health, TLS
fctl logs                  # View facilitator logs
fctl logs all              # View all service logs

Config broken → rollback

fctl backup                # List available backups
fctl restore 20260213-160000
fctl deploy                # Apply restored config

Configuration Reference

config.toml — Signer Keys & Chains

[signers]
evm = ["0xYOUR_EVM_PRIVATE_KEY_HERE"]       # hex, 0x-prefixed
solana = "YOUR_SOLANA_KEYPAIR_BASE58_HERE"   # base58, 64-byte keypair

[chains."eip155:8453"]
rpc = [{ http = "https://base-mainnet.g.alchemy.com/v2/$KEY" }]

RPC tip: Do NOT use free public RPCs in production. Use Alchemy, QuickNode, dRPC, or Helius (Solana).

Caddyfile — Domain & TLS

Replace facilitator.qntx.fun with your domain. Everything else is pre-configured (auto-TLS, rate limiting, security headers).

Security Notes

• Facilitator binds to 127.0.0.1:8080 — not exposed to the internet
• Only Caddy (80/443) is publicly accessible
• config.toml is chmod 644 and gitignored
• Recommended firewall: ufw allow 80,443/tcp && ufw deny 8080

Cloudflare (Optional)

If using Cloudflare proxy:

1. Set SSL/TLS mode to Full (strict)
2. Enable Always Use HTTPS
3. Restrict firewall to Cloudflare IP ranges only