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Backend Systems & API Development

I build secure, solid backends for modern web apps: APIs, database design, login, AI workflows, payments, and third-party tools. I build for reliability and for the long run.

Real-World Expertise

  • I built the full WidgIq backend. It runs the AI chat, the embeddable widgets, the knowledge base, user accounts, analytics, and billing.
  • WidgIq's API key sits in the customer's page HTML, so anyone can see it. I built the security as if the key were already public. Every request is checked against the customer's verified domain, keys are stored only as one-way hashes, and each chat session gets a short-lived signed token. There's no wildcard CORS, and chat, contact form, and config each have their own Redis rate limits. If a key leaks, the owner can replace it in one click and the old one stops working immediately.
  • Each customer's data is separated at the database level, so one project's knowledge base, chat history, and analytics can never show up in another.
  • I built a pay-as-you-go credit system with Dodo Payments. Every payment webhook is verified, and credits sync automatically with API key usage.
  • On WidgIq, BeBetter.ai, GroundUp Pulse, and NexFlow, I designed databases that can grow and type-safe APIs, so the frontend, backend, and outside services work together reliably.

Tech Stack

Node.jsNext.js API RoutestRPCTypeScriptPostgreSQLDrizzle ORMPrisma ORMBetter AuthKinde AuthRedis (Upstash)InngestpgvectorSocket.IODockerGoogle CloudCloudflare Workers

What You Get

A Backend That Can Grow With YouSecure APIs, Login, and Protection Against AbuseSmooth Integrations With Payments and DatabasesCustomer Data Kept Separate and SafeFast APIs

Got something you want built?

I'll build it properly, start to finish, a polished, production-ready product — and if my experience can improve the idea along the way, I'll speak up.

Related Services

Full-Stack Web Development

Your whole product built by one person, from the database to the live site.

AI Integration & LLM Features

AI that fits naturally into your product, not stuck on as an afterthought.

Performance Optimization

Faster pages, smaller bundles, fewer wasted requests.

Frontend Development

Interfaces that are fast, easy for everyone to use, and easy to update.

Maintenance & Support

Keep your product running without hiring a full-time developer.

Cloud Deployment & DevOps

Get your app live, secure, and easy to redeploy.

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