Symfony backend Senior developper

Lead backend development on a production Symfony stack: maintain and evolve API and domain layers, optimize high-traffic endpoints, implement async processing with RabbitMQ, manage subscription/billing workflows, integrate payment providers and analytics, strengthen API security, improve CI/CD and developer experience, and mentor the engineering team., We’re looking for an experienced Senior Symfony Backend Developer to own and evolve our API and domain layer. You’ll maintain and optimize an existing, complex codebase, ship new features and integrations, and help raise the bar on architecture, testing, and operational quality. You should be comfortable using AI coding tools as part of your daily workflow., * Lead backend development with Symfony 7.4, API Platform, and MongoDB (Doctrine ODM)

• Design and implement API resources, custom operations, filters, and security rules
• Optimize high-traffic endpoints and high-volume traffic/consumption processing
• Evolve asynchronous processing with Symfony Messenger and RabbitMQ (workers, retries, routing)
• Own subscription lifecycle logic (workflows, entitlements, plan changes, top-ups)
• Integrate and maintain payment providers (e.g. Paddle, crypto gateways)
• Develop and maintain data pipelines between MongoDB and ClickHouse for analytics
• Strengthen API security (JWT, OAuth, authorization, rate limiting)
• Improve CI/CD and developer experience with Docker and GitHub Actions
• Use AI coding tools (Cursor, Claude, Codex, or similar) to accelerate delivery while keeping code reviewable and high quality
• Lead code reviews and mentor teammates

Technical Skills & Experience

• Symfony expertise: 5+ years professionally with Symfony, including Security, Serializer, Validator, Messenger, and Workflow
• API development: Strong experience with API Platform (or equivalent REST API frameworks) - custom operations, DTOs, filters, extensions
• Document databases: Hands-on MongoDB + Doctrine ODM, including schema design, indexing, and query optimization for large datasets
• Message queues: Production experience with RabbitMQ or similar brokers for async workloads
• Performance: Ability to optimize PHP apps for throughput, memory, and latency
• Security: Solid grasp of web security, JWT auth, and safe payment/callback handling
• Quality: Comfortable with automated testing (PHPUnit), static analysis, and code review standards
• AI-assisted development: Practical experience working with AI tools such as Cursor, Claude, or Cortex - writing effective prompts, reviewing AI-generated code critically, and integrating these tools into a productive engineering workflow

Must-Have Knowledge

• Symfony 7.x architecture, DI, event subscribers/listeners, and Messenger workers
• API Platform custom operations, filters, and Doctrine extensions
• MongoDB indexing strategies and aggregation/query optimization
• RabbitMQ / Messenger patterns (routing, retries, failed messages, consumers)
• Domain modeling for subscription/billing flows (state machines / workflows preferred)
• PHP 8.x+ features and modern typing practices (readonly, enums, attributes)
• JWT authentication and API authorization best practices
• Docker-based local development and CI workflows

Desirable Experience

• ClickHouse or similar analytical databases
• Redis (caching, rate limiting, clusters)
• Subscription billing and payment gateway integrations (Paddle, crypto, etc.)
• Product analytics / CRM integrations (PostHog, HubSpot, Intercom, Sentry)
• Multi-factor authentication
• Architecture fitness tools (PHPStan, PHPArkitect) and parallel test suites
• OAuth2 / social login flows

What We Offer

• 20 days paid annual leave
• 5 paid sick days
• US$800/year office and equipment allowance
• Quarterly profit-sharing
• Full remote work
• High autonomy and direct access to company decision-makers
• Collaborative team with experienced developers
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We’re building a sophisticated backend for a proxy/data service with a subscription-based business model. Our stack runs on PHP 8.4, Symfony 7.4, API Platform 4.2, MongoDB, and RabbitMQ, with ClickHouse for analytics and Redis for caching and rate limiting. We integrate multiple payment providers and product analytics tools to power a scalable, production-grade platform.