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Senior Backend Developer (PHP)

  • Hybrid
    • Delft, Netherlands

Job description

Why you belong in our technology team:

  1. You know that feeling - that ‘yeah!’ moment when your code goes live and instantly impacts millions of users. That’s what we’re looking for.
  2. You also see that the future of e-commerce lies in marketplaces. That’s why you’re eager to build the financial infrastructure that makes it possible.
  3. You thrive in an environment where everything revolves around tech. That’s why we’ve transformed an entire new location into a tech-only office, with all the tools, inspiring workspaces, and (not unimportant) the best coffee in Delft.


What you’ll do as a Senior Backend Developer at Online Payment Platform

What started as five people, a small office, and a few nerf guns (to stay awake) has now grown into one of Europe’s fastest-growing fintechs. With 100+ developers, offices in Delft, Berlin, and London, and Worldline as a partner, we have the perfect mix: the resources of a global player with the energy of a scale-up. At OPP, we build the technology that powers the next generation of e-commerce. From eBay to Ikea, billions in transactions already flow through our systems. We don’t just handle payments—we enable platforms to accept, hold, and disburse funds securely.

As a senior developer, you’ll join one of our four tech teams, working on the architecture of our platform: a scalable backend that processes big data for more than 10 million users. We’re disruptive: we build everything ourselves, from the ground up. You’ll combine strategic thinking with hands-on implementation, knowledge-sharing, and creative programming. As a team, we strive for scalable code with long-term maintainability, Fort Knox-level security, and replacing legacy systems with microservices.


Projects on our roadmap:

  • In-person payments (POS): Currently, OPP only offers online e-commerce payments. However, more and more platforms are also looking for in-person payment solutions via a POS system—think of ordering platforms for restaurants.
  • Horizontal platforms: We currently focus on vertical platforms, where all connected merchants belong to a specific category (such as leisure, crowdfunding, or second-hand sales). We want to support horizontal platforms as well, like Shopify, where merchants from different categories operate. While this may seem like a small step, it’s a major technical challenge.

Job requirements


Your profile

  • Deep experience with PHP and MySQL in high-stakes environments
  • Mastery of Laravel and/or Symfony frameworks
  • Proven track record with high-traffic platforms and microservices
  • Expert knowledge of TDD, PHPUnit, and CI/CD
  • You don’t have to Google TDD, PHPUnit, and Continuous Integration/Deployment. If the same goes for Varnish, Redis, and Queues, we might let you win at Call of Duty ;)
  • Ability to communicate complex technical concepts clearly with different departments
  • For this role, we are looking for someone residing in the Netherlands.


Our offer

  • If you bring the skills and customer-first mindset, we offer:
  • A total yearly salary of up to €89,000
  • A modern, flexible workplace with hybrid working
  • 24 vacation days and 2 supercharge-me-days ⚡
  • 12-month contract with the possibility of permanent extension
  • The tools you need: a MacBook, home office setup, and NS Business Card
  • A developers-only office at Lange Geer 26, within walking distance of our sales and product teams in the heart of Delft
  • A great work atmosphere with catered lunches and regular team drinks


From contact to contract



Want to know more about our projects? 

Let’s talk! We’ll tell you everything you need to know. Send your CV or get in touch with our tech recruiter Gijs Cooijmans at gijs.cooijmans@onlinepaymentplatform.com or +31 6 31328865.





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