Sr. Symfony Engineer - PHP (Remote, Full-Time) [AR024]

Lever, Inc.; United States; Remote; USD 140,000 - 190,000; Full time

Job summary

Smart Working is seeking a Senior PHP/Symfony Engineer to own backend development within a mature Symfony platform that supports enterprise clients. You will lead the Symfony 6.x to 7 upgrade, work with Angular/TypeScript and Python AI microservices, and contribute across a remote cross-functional squad.

This role emphasizes an architect mindset, strong independence, and rigorous code-review of AI-generated and human-written code while maintaining high security and data protection standards.

Qualifications

• 8+ years of commercial software engineering experience, including at least 5 years working with PHP.
• 7+ years of Expert-level PHP development experience.
• 3+ years of recent commercial experience with Symfony 6.x/7 at Advanced level; Laravel transferable.
• 4+ years of Advanced experience in backend architecture, system design and scalability.
• 2+ years of Advanced experience using AI development tools critically.
• 5+ years of Advanced MySQL experience; PostgreSQL also considered.
• At least 1 year of experience with Angular/TypeScript; React/Vue acceptable with TS exposure.
• 3+ years of Advanced experience with PHPUnit.
• 1 year of experience upgrading frameworks and modernising legacy codebases.
• 2+ years of Intermediate AWS experience; Azure/GCP may be considered.
• Fluent written and spoken English.
• Strong communication skills for remote work.
• Ability to work UK hours.

Responsibilities

• Take ownership of backend development within the core Symfony application, delivering work independently within 2–3 months.
• Review and critically assess code written by team and AI tools, challenging approaches and ensuring key considerations are addressed.
• Support migration from Symfony 6.1 to Symfony 7 by resolving versioning and legacy issues.
• Improve performance, scalability, and maintainability of the application.
• Collaborate with Angular front end, TypeScript, and Python AI services; coordinate with DevOps on backend changes.
• Read Angular/TypeScript codebase; front-end exposure is not required.
• Understand wide impact of technical decisions across Symfony, Angular, and AI services.
• Identify root causes and seek better approaches beyond ticket completion.
• Deliver maintainable solutions within a legacy codebase at a steady pace.
• Work autonomously in a remote, cross-functional team.
• Follow SOC 2, PII, and security requirements without exception.

Skills

Architectural mindset

Remote collaboration

English proficiency

Independent work

Code review

Tools

PHP

Symfony

Angular

TypeScript

Python

MySQL

PostgreSQL

PHPUnit

AWS

CI/CD

Job description

About Smart Working

At Smart Working, we believe your job should not only look right on paper but also feel right every day. This isn’t just another remote opportunity — it’s about finding where you truly belong, no matter where you are. From day one, you’re welcomed into a genuine community that values your growth and well‑being.

Our mission is simple: to break down geographic barriers and connect skilled professionals with outstanding global teams and products for full‑time, long‑term roles. We help you discover meaningful work with teams that invest in your success, where you’re empowered to grow personally and professionally.

Join one of the highest‑rated workplaces on Glassdoor and experience what it means to thrive in a truly remote‑first world.

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

• Take ownership of backend development within the core Symfony application, becoming fully independent in delivering work within 2–3 months of joining.
• Review and critically assess code written by the team and AI tools, challenging proposed approaches and making sure key considerations have been properly addressed.
• Support the migration from Symfony 6.1 to Symfony 7 by resolving versioning, compatibility and legacy issues currently preventing the upgrade.
• Improve the application’s performance, scalability and maintainability, making it easier and safer to introduce new functionality.
• Work across the Angular front end, TypeScript and Python‑based AI agent services, collaborating with DevOps where backend changes impact other areas of the system.
• Be comfortable reading and understanding the Angular/TypeScript codebase, even though the role is primarily backend focused. Strong front‑end development experience is not required.
• Understand the wider impact of technical decisions across Symfony, Angular and AI services, while spotting gaps or issues in both human‑written and AI‑generated code.
• Question existing approaches, identify root causes and look for better ways of building things rather than simply completing assigned tickets.
• Deliver thoughtful, maintainable solutions within a legacy codebase while maintaining a consistent pace of delivery.
• Work with a high level of autonomy and ownership while collaborating effectively with a remote, cross‑functional team.
• Follow SOC 2, PII and security requirements consistently and without exception.

Requirements

• 8+ years of commercial software engineering experience, including at least 5 years working with PHP.
• 7+ years of Expert‑level PHP development experience.
• 3+ years of recent commercial experience with Symfony 6.x/7 at Advanced level. Strong senior‑level Laravel experience may be considered where the experience is clearly transferable and the candidate has a good understanding of the differences between Laravel and Symfony.
• 4+ years of Advanced experience in backend architecture, system design and scalability.
• 2+ years of Advanced experience using AI development tools critically, including reviewing, validating and challenging AI‑generated code rather than accepting it without question.
• 5+ years of Advanced MySQL experience, including database schema design and query optimisation. Equivalent depth of experience with PostgreSQL or another relational database may also be considered.
• At least 1 year of experience working with or understanding Angular/TypeScript. Experience with React or Vue using TypeScript may also be considered, but some front‑end exposure is essential.
• 3+ years of Advanced experience with automated testing using PHPUnit. Experience with Pest or another equivalent PHP testing framework may also be considered.
• At least 1 year of Intermediate experience working on framework upgrades and modernising legacy codebases. Experience with major‑version upgrades or significant refactoring in other large PHP applications may be considered.
• 2+ years of Intermediate AWS experience. Equivalent experience with Azure or GCP may also be considered.
• Fluent written and spoken English.
• Strong written and verbal communication skills, with a demonstrated ability to work effectively in a remote environment.
• Ability to work UK hours.
• Ability to successfully complete strict background checks and adhere to PII and data protection requirements.
• Strong self‑sufficiency, with the ability to operate independently and without handholding after 2–3 months, while continuing to collaborate effectively with the wider team.
• A hands‑on engineering approach combined with an architectural mindset, with the ability to understand how and why the wider system works rather than focusing only on writing 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.