CelLink Internal Tooling Platform
Fifteen-plus production internal tools for validation, reporting, and ETL, owned end to end across two sites.
- 15+ production tools
- 500+ users
- 99.9% uptime
Context
A high-velocity startup scaling across two sites needs internal software the off-the-shelf market doesn’t sell: data movement between systems that were never meant to talk, reporting, and validation. When that software is wrong, the cost lands immediately. That whole surface became mine to own.
What I built
A suite of 15+ internal tools serving 500+ users across both sites: validation systems, an admin tool, automated reporting, and the ETL pipelines that feed them. Not one app. A platform of small, focused tools, each one solving a real operational bottleneck, all maintained by one engineer.
Architecture
Services are Python/FastAPI and C#/.NET against SQL Server, with Apache NiFi moving data between systems and React on the operator-facing interfaces. Each tool stays small and single-purpose, but they share conventions for data access, validation, and deployment. That shared spine is what lets one person own 15+ tools without the set rotting.
Technical highlights
- Validation that gates release. These systems decide whether work passes, so being down is not an option. They run at 99.9% uptime.
- Reporting automation. Replaced a manual reporting process with an automated pipeline, so the report is a byproduct of the data instead of someone’s afternoon.
- One admin surface. Folded scattered manual operations into a single tool, so day-to-day administration stops being tribal knowledge.
Tradeoffs
Many small tools owned by one engineer only works under ruthless consistency. Every tool that drifts from the shared patterns is a tool only I can touch, and that doesn’t scale. I’d rather give up a little local cleverness to keep the whole set legible. The discipline is the price of the breadth.
Outcome
The toolset is core operational infrastructure at both sites, used daily by 500+ people. It’s also where I learned what it takes to ship software an organization genuinely leans on, and to keep it standing.