surstrom documentation

surstrom is a payment routing platform that connects Clients (merchants who need to accept payments) with Relays (operators who process payments).

How It Works

  1. Client creates a payment via API with amount, currency, and external ID
  2. surstrom selects the best available Relay from the payment pool using LRU routing
  3. The payment is processed through the Relay's provider (e.g. Stripe)
  4. On success, Solana settlement is sent from the Relay's reserve to the Client's wallet
  5. The Relay earns the fee on every completed payment — the difference between their configured fee and the provider + settlement costs. The Client receives the remainder

Two Roles

Every user is either a Relay or a Client. The role is chosen at signup and cannot be changed.

Architecture

Payment Flowtext
Client (API) → surstrom → Payment Pool → Relay provider → Settlement (Solana) → Client
  • Payment Pool — Relays join a shared pool to receive payments. Routing uses LRU (Least Recently Used) to distribute load evenly.
  • Settlement — After a successful payment, settlement is sent from the Relay's wallet to the Client's wallet on Solana. The Relay earns the fee margin — the difference between their fee and the Solana transaction cost.
  • SDK — A JavaScript snippet that Relays embed on their standalone pages. It mounts the payment form and reports payment status back.
  • Encryption — All sensitive data (API keys, card details, wallet keys) is encrypted at rest using AES-256-GCM.
  • 2FA — TOTP-based two-factor authentication is required for withdrawals.

Roles

Relay

Relays process payments for Clients and earn a fee on every completed transaction. They:

  • Connect payment providers with restricted API keys
  • Set their own fee percentage per provider (typical range: 5–10%)
  • Configure routing rules (min/max amounts, daily limits, country blocking)
  • Install the SDK on their standalone pages
  • Join the payment pool to receive routed payments
  • Earn the fee margin on every completed payment — the difference between the Relay's fee and the provider + settlement costs

For example, on a $100 payment with a 7% Relay fee and Stripe at 2.9% + $0.30: the Relay earns $7.00, pays $3.20 to Stripe, and nets ~$3.80 profit. The Client receives $93.00 via Solana settlement.

Client

Clients are merchants who accept payments. They:

  • Generate an API key from the dashboard
  • Create payments via POST /api/payment/init
  • Embed the returned relayPage URL on their site
  • Receive Solana settlements for their share of completed payments
  • 1% of each payout is frozen for 45 days in case of a dispute

Next Steps