Available to hire
Hi, I’m Darko Potajac, a Backend Software Engineer with 5+ years of experience delivering high-performance web applications for global clients in SaaS, FinTech, and e-commerce. I specialize in PHP 8, Laravel, RESTful APIs, MySQL, and PostgreSQL, and I’m passionate about clean architecture and writing maintainable code.
I practice test-driven development (TDD) and aim to improve performance and delivery through automated tests (PHPUnit) and thoughtful design. I enjoy collaborating in Agile teams, mentoring peers, and shipping reliable backend systems that scale.
Skills
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Language
English
Fluent
Work Experience
Backend Developer at MMS CodeBackend
January 2, 2021 - August 2, 2022Creating new features, API, validating data and CRUD operations, creating MVC models in several projects.
Backend Developer at IQ Agency
August 2, 2022 - PresentCreating API endpoints, communication with the database, creating new features in the application, and debugging.
Full-Stack Software Engineer (Part-time Contract) at The Bridge
January 1, 2025 - PresentDelivered enterprise-grade Laravel/Vue.js applications for 3+ Saudi Arabian clients, enforcing clean architecture and MVC best practices across all projects. Designed RESTful APIs powering business-critical modules, reducing average API response time by 35% through query optimization and Redis caching. Architected PostgreSQL relational schemas for 2 high-traffic platforms, cutting complex query execution time by 40%. Introduced PHPUnit unit tests covering 80% of core service layer, eliminating a class of recurring regressions. Led Git branching strategy (GitFlow) across a 5-person engineering team, reducing merge conflicts by 60%. Coordinated with frontend, QA, and PM teams in 2-week Agile sprints, maintaining on-time delivery rate above 90%.
Backend Software Engineer (Full-time) at Eton Digital
August 1, 2022 - PresentEngineered RESTful API endpoints serving 1M+ monthly requests for clients across SaaS, FinTech, and e-commerce verticals. Optimized MySQL/PostgreSQL queries via advanced indexing and relational modeling, improving read performance by 30–40% across 6 key modules. Delivered backend features end-to-end across 15+ production releases, reducing average feature rollout time by 20%. Established PHPUnit TDD practices, increasing automated test coverage from 12% to 68% over 18 months. Diagnosed and resolved 50+ production incidents, reducing MTTR by 45%. Refactored 3 legacy monolithic service layers into microservices, improving deployment frequency by 3×. Mentored 2 junior developers in Laravel, clean architecture, and unit testing.
Backend Software Engineer (Full-time) at MMS Code — Custom Web Applications
January 1, 2021 - August 1, 2022Built and deployed RESTful APIs for 8+ client projects, supporting web applications and third-party integrations from scratch. Implemented MVC-structured Laravel applications with clean separation across models, controllers, and service layers. Designed normalized relational database schemas and optimized SQL queries, reducing average query time by 25%. Introduced server-side validation and business logic layers, reducing data integrity errors by 90% across affected modules. Collaborated with frontend developers to define API contracts, cutting integration bugs by 30% per release cycle.
Education
Bachelor Degree at Pan-European University APEIRON Information Technologies
October 1, 2017 - November 1, 2021Java programming course at LANACO
March 1, 2022 - June 1, 2022Bachelor of Computer Science at University of Banja Luka, BiH
October 1, 2017 - November 1, 2021Qualifications
Industry Experience
Software & Internet, Professional Services, Financial Services, Retail
Skills
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