Full-Stack Software Engineer
Full-stack products. Production systems that scale.
I'm Mohammed Sinan, a Full-Stack Software Engineer with 5+ years of experience building and operating production SaaS products and high-traffic web platforms with TypeScript, Node.js, NestJS, React, and Next.js.
Selected work
View all →LocalEyes AI
LocalEyes AI
Architected and developed a multi-tenant NestJS SaaS backend for Google Business Profile management, local rank tracking, billing, and AI-powered audits.
- Multi-tenant NestJS API
- Bidirectional Google profile sync
- Reliable BullMQ workers
Optimiza
Koora Kings
Built and scaled the Node.js / Sails.js backend for Koora Kings — prediction contests, salary-cap fantasy, and live sports scoring at production scale.
- 2M+ predictions
- ~180 REST APIs
- Millions of prediction records
Optimiza
Riyadh Season
Developed and maintained a 30+ page production web platform integrated with a CMS, modernizing its architecture, performance, and deployment workflow.
- 30+ page platform
- 24% performance improvement
- 34s deploy pipeline
Latest writing
View all →Why Multi-Tenant APIs Should Scope Ownership Through Headers, Not Request Bodies
Trusting tenantId or workspaceId from a POST body is an IDOR waiting to happen. When header-based tenancy scoping is the right call — and how to implement it cleanly.
Eliminating Cache Stampedes on Match Day
How single-flight deduplication and stale-while-revalidate caching fixed MySQL connection-pool exhaustion during peak fantasy sports traffic.
Building a Resilient AI Audit Pipeline
How we designed a multi-stage NestJS pipeline with deterministic LLM fallbacks, contract validation, and reproducible audit cycles for a local SEO SaaS.