Senior solo full-stack engineer. AI, backend, web3.
I'm Sajid. I build production systems alone — architecture, code, infrastructure, ops, end-to-end. The kind of work usually spread across a small team, run by one person who can hold the whole shape in their head.
For three years I was the only engineer at Darkblock, building a decentralized unlockables platform that served thousands of users and an SDK partners integrated against. Since 2024 I've been independent — shipping production AI for a private client (Tenure — ~330K LOC, hybrid retrieval, voice, multi-format ingestion) and a Web2.5 film-distribution platform (Pureland — live at purelands.biz, 11 weeks blank-repo to production, three payment rails, Cloudflare Workers decrypting at the edge).
What I do well: take a vague mandate, hold the architectural shape in one head, ship it correctly the first time. What I don't do: customer-facing engineering, sales-engineering, dev-rel as a primary role.
What I reach for.
- ›RAG / hybrid retrieval (BM25 + vector + RRF)
- ›Knowledge-graph construction
- ›LLM orchestration & persona systems
- ›Embeddings · semantic search · prompt engineering
- ›OpenAI SDK (provider-agnostic)
- ›NestJS · FastAPI · Node.js / Express
- ›TypeScript · Python
- ›Microservices · event-driven architectures
- ›BullMQ · Redis · Prisma ORM
- ›Unlock Protocol · ethers.js v6 · Polygon
- ›Thirdweb SDK · SIWE wallet auth
- ›Arweave (via Irys)
- ›Smart-contract integration & signature verification
- ›Web Crypto API
- ›AWS (Step Functions, Lambda, ECS Fargate, ALB, Amplify, S3, OpenSearch, Secrets Manager)
- ›Cloudflare Workers + KV
- ›Docker · GitHub Actions CI/CD
- ›Fly.io · Firebase · Nginx
- ›PostgreSQL · MongoDB · DynamoDB
- ›Elasticsearch · OpenSearch
- ›Vector databases
- ›Looker · Metabase
- ›React 19 · Next.js 15 (App Router) · Tailwind
- ›React Native
- ›Android SDK · iOS SDK · Swift · Kotlin
- ›Stripe
- ›PayPal REST v2 (OAuth2 + webhook verification)
- ›Unlock Protocol checkout