Fullstack Software Engineer (For Independent Contractors)

EUR 50-100 per hour
MIDDLE
✅ Hybrid ✅ On-site
✅ Contract / Freelance

Used Tools & Technologies

Not specified

Required Skills & Competences

Security @ 3 TypeScript @ 3 Java @ 3 Communication @ 3 Perl @ 3 React @ 3 Experimentation @ 3 Design Patterns @ 3 Spring Boot @ 3

Details

A Software Engineer II owns the execution of technical elements in the Booking.com tech stack, products and processes. They are responsible for the implementation of technical solutions based on business requirements, can estimate effort and impact, and deliver high-quality production and test automation code. Software Engineer II works with colleagues across roles to design, prioritise and implement technical tasks and can focus on product features, infrastructure automation, frameworks, tooling or services.

Responsibilities

  • Build software applications using relevant development languages and apply knowledge of systems, services and tools appropriate for the business area.
  • Write readable and reusable code using standard patterns and libraries.
  • Refactor and simplify code; introduce design patterns when necessary.
  • Ensure application quality by following standard testing techniques and methods that adhere to the test strategy; test automation quality is emphasized.
  • Maintain data security, integrity and quality by following company standards and best practices.
  • Own services end-to-end: monitor application health and performance, set and monitor relevant metrics and act when violated.
  • Reduce business continuity risks and bus factor by using best practices and writing documentation such as runbooks and OpDocs.
  • Use continuous delivery and experimentation frameworks to reduce risk and obtain customer feedback.
  • Independently manage application deployment and production operations.
  • Address and resolve live production issues, mitigate customer impact within SLA, and contribute to postmortems.
  • Provide architectural guidance: advise product teams toward technical solutions that meet functional, nonfunctional and architectural requirements.
  • Evaluate architecture solutions taking into account cost, business and technology requirements; describe implications of system changes.
  • Identify opportunities for process, system and structural improvements and design/implement relevant improvements.
  • Deliver clear, well-structured communication tailored to the audience and practice active listening.

Requirements

  • Proven experience as a Software Engineer with the ability to implement technical solutions and own services end-to-end.
  • Strong emphasis on producing high-quality production code and test automation.
  • Experience with monitoring, incident management, metrics and production operations.
  • Ability to perform root cause analysis and contribute to postmortem processes.
  • Capability to provide architectural guidance and evaluate design trade-offs.
  • Strong critical thinking and communication skills.

Required tech stack

  • Backend: Java (Spring, Spring Boot). Perl would be a plus.
  • Frontend: TypeScript, React.

Contract & logistics

  • Location: Amsterdam, NH, Netherlands
  • Hours: 40 hrs/week
  • Timeline: 3 months (Starts: Jun 1, 2026 — Ends: Aug 31, 2026)
  • Payrate range: 50 - 100 €/hr
  • Project ID: 12659-1