Senior PHP/Symfony Engineer

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About the Role

As a Senior PHP/Symfony Engineer, you will take hands-on ownership of backend development within a mature Symfony platform that manages marketing and revenue data for enterprise customers. The core application currently runs on Symfony 6.1, with an upgrade to Symfony 7 planned, alongside an Angular front end and TypeScript and Python AI agent microservices.

This is a strongly backend-weighted, senior hands-on engineering role requiring an architect mindset, strong independence, and the ability to understand how technical decisions affect the wider system. You will work within a remote, cross-functional product squad alongside engineering, product, QA, and DevOps colleagues.

Responsibilities

• Own and deliver backend work in the core Symfony application, working fully independently within 2–3 months of starting.
• Critically assess code produced by the team and by AI tools, challenging proposed solutions and ensuring important aspects have been properly thought through.
• Help move the application from Symfony 6.1 to Symfony 7, resolving versioning and legacy issues currently blocking the upgrade.
• Improve application performance, scalability, and maintainability so new features are easier and safer to add.
• Work with the Angular front end, TypeScript, and Python AI agent services, and the DevOps team where backend changes cross those boundaries.
• Read and reason about the Angular/TypeScript codebase despite the role being strongly backend weighted; strong front-end development skills are not required.
• Understand how decisions affect the wider system, including Symfony, Angular, and AI services, while identifying detail gaps in code and AI-generated output.
• Challenge solutions, identify root causes, and improve how things are built rather than simply completing tickets.
• Deliver well-reasoned, maintainable solutions within a legacy codebase while maintaining a steady delivery pace.
• Work with high autonomy and accountability while collaborating effectively within a remote, cross-functional squad.
• Respect SOC 2, PII, and security controls without exception.

Requirements

• 8+ years of commercial software engineering experience, including 5+ years in PHP.
• 7+ years of PHP experience at Expert level.
• 3+ years of recent commercial Symfony 6.x/7 experience at Advanced level. Very senior Laravel experience that is clearly transferable may be considered, provided you have a solid understanding of how Laravel and Symfony differ.
• 4+ years of Advanced experience in backend system design and scalability.
• 2+ years of Advanced experience critically using AI tooling, including reviewing and challenging AI-generated output rather than accepting it blindly.
• 5+ years of Advanced MySQL experience covering schema design and query optimisation. PostgreSQL or another relational database at the same depth may be considered.
• 1+ year of Angular/TypeScript awareness. React or Vue with TypeScript may be considered, but zero front-end exposure is disqualifying.
• 3+ years of Advanced automated testing experience with PHPUnit. Pest or equivalent PHP testing frameworks may be considered.
• 1+ year of Intermediate experience with framework upgrades and legacy-code modernisation. Major version upgrades or refactoring in other large PHP codebases may be considered.
• 2+ years of Intermediate AWS experience. Azure or GCP may be considered.
• Fluent written and spoken English.
• Strong written and verbal communication and a proven record of working effectively remotely.
• Ability to work UK hours.
• Ability to pass strict background checks and comply with PII policies.
• Strong self-sufficiency, with the ability to work with zero handholding after 2–3 months while continuing to collaborate effectively.
• A hands-on technical approach with an architect mindset: understanding how and why the system works rather than only producing code.

Nice to Have

• 2+ years of Intermediate CI/CD experience with GitHub Actions; GitLab CI, Jenkins, or Azure DevOps are suitable alternatives.
• Basic experience with Amazon Redshift or data warehousing; Snowflake or BigQuery may be considered.
• Azure exposure alongside AWS.
• Previous project leadership experience.
• Previous mentoring and technical leadership experience with other engineers.