Greg Wierzba
Senior Software Engineer · Backend, Architecture & AI
Profile
Engineer with 14+ years across backend, web platforms, technical leadership, and legacy
modernization.
Strong in PHP/Symfony and API integrations, pragmatic architecture, testing, delivery automation.
Currently focused on TypeScript/Bun/Svelte/PostgreSQL systems and AI-assisted engineering workflows.
Experience
Software Engineer at Mennica Polska S.A.
- Delivered KSeF integration for MPK Wrocław in an existing invoicing system, covering business and individual-customer invoices.
- Implemented a Customer Support System for MPK Suwałki; maintained PHP/PostgreSQL systems spanning PHP 5.2 legacy code to PHP 8.
Independent Software Engineer
- Build backend and full-stack projects with TypeScript, Bun, Svelte/React, Hono, PostgreSQL, and Docker.
- Develop AI-assisted engineering workflows around LLM agents, RAG, prompting, code review, and architecture review.
Senior Developer / Deputy Team Leader at OnTheGo Systems
- Developed WPML installation/update systems and integrations with account, support, and translation platforms.
- Led release preparation, compatibility testing, internal automation, and cross-functional technical coordination; also served as Agile Facilitator.
Senior PHP Developer at eSky.pl
- Built and maintained Symfony/MySQL applications and internal libraries using TDD with PHPUnit and Behat.
- Worked in CI/CD with Jenkins, Git, and Docker; delivered internal tooling and external API integrations, including Azure Translator.
Technical / Team Leader & Senior Developer at TravelTECH
- Led engineers and modernized legacy PHP code through refactoring, unit testing, and cleaner architecture.
- Designed and implemented partner integrations with Amadeus, Travelport, and Chartis APIs.