Senior Backend Engineer · PHP / Symfony · APIs · SQL & Production Systems
Backend engineer with 11+ years in IT. I work mainly with PHP and Symfony on API integrations, SQL performance and existing production systems. React and TypeScript are secondary skills.
Based in Montenegro · Open to remote roles
- Integrations: connecting systems through REST and SOAP APIs, including payment integrations and authentication with OAuth/JWT.
- SQL performance: analyzing and optimizing slow queries in MySQL and MariaDB with
EXPLAIN. At Colnect this included joins, temporary tables andUNION ALL. - Existing systems: debugging and troubleshooting production code, and improving it through incremental changes.
Main tools: PHP, Symfony, MySQL / MariaDB, PostgreSQL, Redis, Docker, Nginx, Linux, Git, PHPUnit and CI/CD. I also work with React and TypeScript.
- Independent B2B developer, since September 2017. Freelance software development. Some of it is under NDA, so it is not described here.
- Colnect, 2021–2022. Symfony backend development and MariaDB query optimization.
- OneBrain AI, 2023. Internship: React work on real-time synchronization.
- Additional experience. Blockchain: Bitcoin PSBT/UTXO work, a Top 200 result in Summer of Bitcoin and a Solidity/Web3 competition in 2023. WordPress: custom plugins and themes, mostly non-commercial.
The repositories below are portfolio projects, not that work.
Both are technical assignments and portfolio projects, not commercial products.
Symfony 7.4 REST API for authors and books, built to a fixed specification.
- Filtering, pagination and sorting
- Separate
PUTandPATCHsemantics - Request-to-DTO mapping with validation
- Writes dispatched as Symfony Messenger commands (synchronous transport)
- Doctrine migrations on SQLite
- 97 PHPUnit tests, 229 assertions
Symfony 7.2 API for tile orders and prices.
- XML order ingestion (plain XML over HTTP, not a SOAP service)
- External price lookup with a controlled fallback when the provider is unavailable
- Paginated order statistics
- Full-text search with Manticore Search, MySQL and Docker Compose
- 11 PHPUnit controller tests with mocked dependencies
- eth-wallet-dashboard: React / TypeScript dashboard showing Ethereum wallet balance and transactions.
- whatsapp-media-crypto: an experiment, not production-ready. It has known correctness and security issues, is not an official WhatsApp implementation, and no stable release is planned. See its README before using it.