~*~ Mohammed Sayed (cersho), shipping since 2017 ~*~
Senior Software Engineer | Backend Specialist
I'm a software engineer and a lifelong gamer. Most of my work lives on the backend, from designing APIs and shaping service architecture to squeezing out performance and keeping things reliable.
What pulls me in is the hard part: the place where distributed systems, observability, and resilient infrastructure all collide in production.
I build for real-world pressure, heavy traffic, flaky dependencies, and tight latency budgets. My goal is always the same: systems that are simple to reason about, easy to observe, and stubbornly hard to break.
Currently obsessing over Effect: TypeScript where errors are typed, dependencies are explicit and concurrency is structured. It has crept into everything I build.
At work, I'm migrating older services to Effect and building the new ones on it.
Backupd's whole Cloudflare stack is described with Alchemy v2, which is built on Effect.
HISP Vietnam, Software Engineer. Architected and developed a production-grade DHIS2 application for national health information systems, delivering configurable ICD-11 workflows, real-time analytics, digital certification, and interoperable public health reporting. (DHIS2, ICD-11)
Stealth Startup, Technical Lead. Led the architecture and development of cloud-native SaaS platforms, building scalable backend services and full-stack applications while driving technical direction, engineering standards, and long-term platform scalability.
Stealth Startup, Software Engineer. Led the development of scalable SaaS backend systems, designing high-performance APIs and cloud integrations with a strong emphasis on performance, reliability, maintainability, and engineering excellence.
DefendOps, Lead Software Engineer. Led the architecture and implementation of distributed backend systems powering production workloads, leveraging Rust, Go, Node.js, and ASP.NET Core with a strong emphasis on scalability, performance, reliability, and developer experience. (Rust, Go, Node.js, ASP.NET Core)
Freelancing, Software Engineer. Designed and delivered production-grade SaaS platforms, distributed systems, and infrastructure-focused applications for international clients, specializing in scalable architectures, full-stack development, and end-to-end product delivery.
Encrypted, restore-tested backups for PostgreSQL, MySQL/MariaDB, MongoDB and Convex, running entirely on Cloudflare. Every backup is compressed, age-encrypted and verified with scheduled restore tests, with a CLI and TypeScript SDK for CI and code.
fig. 1 · backupd.dev, front page
+----------+------------------------------------+
| Layer | Built with |
+----------+------------------------------------+
| API, web | Cloudflare Workers, TanStack Start |
| Data | D1 (sharded), R2, KV |
| Jobs | Workflows, Queues, Containers |
| Realtime | Durable Objects |
| Infra | Alchemy, Effect |
+----------+------------------------------------+
