Senior Backend Developer – Symfony

Role Overview

• Designing and architecting scalable, high-performance applications
• Leading development of complex features and new systems
• Making key technical decisions and establishing backend best practices
• Optimising performance across databases, caching and application layers
• Improving API performance and overall application speed
• Implementing robust security practices (authentication, authorisation, vulnerability prevention)
• Conducting deep troubleshooting and resolving critical issues
• Mentoring developers through code reviews, guidance and knowledge-sharing
• Collaborating with Product, Frontend and DevOps teams to align solutions with business goals
• Supporting estimation, planning and development workflows
• Ensuring strong test coverage and stable production releases

Requirements

• 5+ years’ experience in backend development
• Deep expertise in PHP and Symfony (including modern Symfony versions)
• Strong understanding of Symfony components, architecture and best practices
• Advanced SQL and Doctrine ORM knowledge
• Experience with performance optimisation, caching and scalable systems
• Solid testing practices (PHPUnit, TDD mindset)
• Experience designing scalable, maintainable architectures
• Confidence mentoring and reviewing others’ code

Tech Stack

• PHP
• SQL
• Symfony

Benefits

• Hybrid working (minimum 3 days per week in our Liverpool or Leeds office)
• A senior role with real technical influence and ownership
• Complex, high-traffic projects that challenge and grow your skills
• A collaborative team that values quality and continuous improvement
• Clear progression opportunities for senior engineers