Senior Backend Developer - PHP & DDD

About the role

Red Tiger, a team within the Evolution ecosystem of 200 professionals based in Sofia, is looking for a Senior Backend Developer for its Backend team. You will help drive the architecture, scalability and domain modelling of a high-concurrency Online Gaming and Betting platform that handles real-time betting and high-volume financial transactions, working alongside the Backend Architect and Engineering Lead.

Key responsibilities

• Design and write high-performance, fault-tolerant PHP code using Domain-Driven Design (DDD) and SOLID principles.
• Lead domain modelling discussions, define Bounded Contexts and establish a Ubiquitous Language between technical and business domains.
• Maintain strict code review standards for code quality, architectural consistency and security.
• Tune performance, optimise databases and refactor legacy components.
• Mentor and guide junior and mid-level developers.
• Work with QA, DevOps and Product leadership to deploy critical backend services reliably.

Required profile

• Extensive hands-on experience in advanced PHP development (PHP 7.4+, PHP 8.x).
• Practical experience applying DDD concepts such as aggregates, entities, value objects, domain events, repositories and bounded contexts.
• Advanced experience with MySQL / MariaDB optimisation, query tuning and indexing under heavy transaction loads.
• Proven track record of building high-throughput, low-latency RESTful APIs.
• Solid experience with JavaScript / Node.js for microservices or real-time event processing.
• Experience with automated testing and TDD/BDD (Codeception, PHPUnit).

Required skills

• Docker and container orchestration, REST APIs, JSON, Git / GitLab.
• Preferred: RabbitMQ, Kafka, Redis, Memcached, Nginx, Apache, and experience in online gaming, FinTech or high-frequency transactions.

What we offer

• A challenging environment in a dynamic international team.
• Company-funded training.
• Flexibility on working hours.
• Multisport/Coolfit card and additional health insurance.