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Tech & Technique
Fastify, React 19, PostgreSQL, TypeScript, Next.js 16, Supabase, Vite, TanStack Query, Tailwind CSS, Zod, Claude API, Caddy, Railway, Cloudflare
Description
A pay-as-you-go proxy platform that resells mobile, residential, and datacenter (IPv4/IPv6/ISP) proxies bought wholesale from upstream vendors, marked up, and sold on a prepaid crypto-balance model. Customers buy and manage proxies through a web dashboard or a versioned public wholesale API. The product spans four independent apps — a hexagonal Fastify backend, a React 19 customer dashboard, a separate React 19 admin panel, and a Next.js 16 marketing/SEO site — all backed by Supabase Postgres with GoTrue auth and row-level security.
Key Features
- Buy and renew 8 proxy types sourced from three upstream vendors
- Prepaid wallet with a full transaction ledger, crypto top-ups, and refund-on-failure
- Idempotent quote → create → provision → renew order lifecycle
- Versioned public wholesale API with scoped, hashed API keys
- Reseller sub-accounts plus referral and affiliate programmes
- Mobile-proxy control — rotation, reboot, fingerprint, and carrier selection
- Claude-auto-translated blog across 4 languages and 320 programmatic-SEO pages
- Full admin P&L control plane with per-vendor kill-switches
- TOTP two-factor authentication and Google OAuth
My Role
I built SotaProxy end to end — architecture, backend, both frontends, the marketing site, and production infrastructure. The core challenge was safe, fully automated proxy sales across multiple vendors while real money moves through every single order.
- Architected a hexagonal Fastify backend — 280+ routes and 100+ use-cases behind 4 ports isolating the domain from vendors, storage, and transport
- Built money-safe commerce on atomic row-locked PostgreSQL RPCs with debit-before-provision, so a failed provision refunds instead of silently charging
- Integrated 3 proxy vendors and 2 crypto payment gateways behind a unified catalog, under strict supplier anonymity
- Engineered a 14-job cron scheduler with balance kill-switches that halt purchasing before upstream credit runs dry
- Shipped the Next.js 16 SEO site with a Claude-translated blog and on-demand ISR revalidation