Smartum Pro

Smartum is where my blockchain work started. I joined in 2016 as a senior backend developer, fully remote before that was normal, and spent two years there while Ethereum itself was barely two years old.

Most of the blockchain work was ICO smart contracts. A deployed contract can’t be patched, so I kept them at 100% test coverage. Tests were the only safety net on offer, and in the ICO era the cost of a bug was other people’s money, immediately and in public.

The rest of the job was backend work with a payments flavor. I built processing for Bitcoin and debit cards side by side (two very different failure modes behind the same checkout button), and a real-time messaging system on RabbitMQ with MQTT that served both mobile and web clients. I also automated code review and deployment, wiring quality checks into the SDLC so shipping didn’t depend on someone remembering to run them.

Looking back it was a good place to start. The team was small enough that I touched everything, and most of the blockchain questions we hit didn’t have answers on Stack Overflow yet.