Senior Full Stack Engineer (PHP)

Are you a Senior Full Stack Engineer who thrives on building scalable web applications and AI-driven tech and looking for high-autonomy impact on a 4 or 5-day workweek (32-40 hours)? Your Mission: As our Senior Full Stack Engineer in Groningen, your mission is to architect, build, and scale core features across our recruitment technology platform. Working across the full software lifecycle, exclusively utilizing Svelte on the frontend and Symfony 8 on the backend, you will help empower hundreds of global enterprises to hire smarter. We are looking for a true software engineer who writes clean, foundational code rather than relying solely on framework-level scripting. Bringing senior-level engineering rigor and a passion for clean architecture, you will turn complex product visions into high-performing, maintainable code. What You Will Do: • Architect, develop, and maintain responsive frontend applications strictly in Svelte and robust backend services exclusively in Symfony 8 across the platform ecosystem. • Collaborate closely with product managers, UI/UX designers, and QA engineers to scope, estimate, and ship scalable, high-impact features in an Agile environment. • Integrate modern AI capabilities, data pipelines, and third-party systems (such as ATS platforms) through reliable RESTful and GraphQL APIs. • Write clean, highly testable, and efficient core code, demonstrating deep language fundamentals and custom software engineering beyond framework-level scripting. • Conduct thoughtful code reviews, champion CI/CD automated workflows, and ensure system reliability, performance, and security. • Identify and execute tech debt refactoring, optimize database/query performance, and troubleshoot complex production issues across the stack. • Share expertise, collaborate asynchronously, and help foster an inclusive, engineering-first culture across our international team. What We Look For: • 10+ years of professional software engineering experience developing full-stack web applications in modern SaaS or tech environments. • 10+ years of deep experience in full-stack engineering, with proven, hands-on mastery of PHP (strictly Symfony framework) and modern frontend development (preferably Svelte). • Strong foundational programming skills, with the ability to write custom, low-level logic and clean architecture from scratch, rather than relying solely on framework abstractions, scripting and AI. • Strong expertise with relational and non-relational databases (e.g., MySQL, MariaDB) and designing scalable REST/GraphQL APIs. • Practical experience with cloud architecture (GCP), containerization (Docker), and modern CI/CD pipelines. • A strong dedication to automated testing practices (unit, integration, e2e) and clean code principles. • Native Dutch speaking, professional fluency in English, with the confidence to articulate technical ideas clearly to both technical and non-technical stakeholders. Why you can’t miss out on this opportunity We take good care of our VONQies and that shows in our benefits package:  • A paycheck that fairly reflects the market and your experience, and of course, monthly pension contributions 🤝 • A MacBook for both business and private use! 💻 • A fixed monthly phone expense allowance 📱 • A premium HeadSpace subscription to recharge your batteries after work.  • Flexible vacation days - that's right, we will not define a specific number, though a fair-usage approach applies to keep all team members happy! ✈️ • 100% reimbursement of your public transport expenses, so you can come to this lovely office worry-free. 🚆 • Still prefer to use your own vehicle? We offer a KM reimbursement, and parking is on us! 🚗 • A hybrid work model - work in the office and from home. ⏰ • Snacks, sodas, co