Senior PHP Backend Engineer - Scale & Modernisation

SHIFTBASE B.V.; Zoetermeer; On-site; EUR 80,000 - 110,000; Full time

Job summary

Shiftbase B.V. is seeking a Senior Backend Engineer to drive platform modernisation and reliability. You will work on core backend systems, turning a mature monolith into modular, scalable services while improving performance and observability.

Collaborate with product and frontend teams to ship high-quality features, define testing strategies, and mentor engineers. Note: Netherlands-based candidates only.

Qualifications

• Deep backend experience with complex, high-scale systems.
• Experience with hexagonal architecture, domain-driven design, or similar patterns.
• Comfort writing raw SQL and working with complex relational schemas.
• Experience modernising legacy systems and breaking monoliths.
• Experience testing in legacy contexts and improving coverage.

Responsibilities

• Drive technical excellence and design scalable backend solutions.
• Design and deliver high-quality, scalable features and system components.
• Make informed architectural decisions balancing pragmatism and long-term vision.
• Set the bar for technical craft via code reviews and mentoring.
• Own complex initiatives from design to production with testable increments.

Skills

Modern PHP & architectural patterns

SQL & database design

Legacy modernisation experience

Monolith to services

Testing in legacy contexts

Tools

PHP

Job description

Shiftbase B.V. is seeking a Senior Backend Engineer to drive platform modernisation and reliability. You will work on core backend systems, turning a mature monolith into modular, scalable services while improving performance and observability.

Collaborate with product and frontend teams to ship high-quality features, define testing strategies, and mentor engineers. Note: Netherlands-based candidates only.