BEATOZ CPG (Core) - Crypto Payment Gateway

Implemented merchant/store APIs including a public merchant list for store pages and a Developer Site registration flow (auto-approve) backed by SSOT API credentials. Built a Strategy/Adapter-based payment orchestrator that selects network adapters, persists QR data as SSOT, and conditionally scans chains for direct transfers (with throttling). Built payment products APIs (integrated payments, widgets, custom payments) with session/status endpoints and supporting services (gas fee calculation/exchange rate). Added custody wallet modules with provider-based key signing, issuer-facing integration hooks, settlement handoff points for treasury-side processing, queue-separated workers/processors for monitoring and settlement, and an HMAC-signed webhook delivery system with retry + persistence for operational reliability.