ViaEurope GmbH
A large Rails application that supports customs clearance and temporary storage for goods imported into the EU. I work with operational teams to turn regulatory and real-world requirements into production features.
- Designed and implemented customs integrations supporting end-to-end B2C and B2B e-commerce imports across Belgium, Germany, Hungary, Italy and the Netherlands, including clearance, pre-arrival declarations, temporary storage and transit.
- Built asynchronous integrations over SFTP, XML and APIs: generated and submitted declarations, polled and parsed responses, correlated messages with internal records, handled rejections and retries, and maintained complete audit trails.
- Made Sidekiq workflows safer with duplicate protection, throttling, recovery logic and explicit state machines; added monitoring and stored message transcripts to make failures easier to investigate and recover from.
- Built REST and GraphQL APIs, control and rejection screens, alerts, reports and customs PDFs used by operational teams.
- Extracted shared logic into service objects, workers, finders and reusable model concerns as the application moved towards a modular monolith. Rolled out changes behind feature flags.
- Redesigned the tariff data model behind customs duty calculations so the system could use rates from a specific date while keeping day-to-day queries fast. I first explored the approach in a self-initiated Clojure prototype, importing approximately 4 GB of Dutch tariff XML into PostgreSQL and experimenting with agent-assisted development.