Senior PHP web developer / system architect

We are Onyx. We are looking for talent.

We are a Belgian scale up active in contractor management. We developed an online platform that allows companies to register, qualify and train their contractors, contractors and suppliers. The platform allows access to industrial sites and ensures that only qualified people go to work. It streamlines communication between contractors and manufacturers from different industries. Onyx One operates is 44 countries and includes more than 65,000 contractors.

Onyx One employs 15 people in Belgium, and has teams in several countries, inside and outside Europe. Team spirit, collaboration and co-creation are part of our DNA.


You focus on the further development of Onyx One. Your gaze is always future-oriented so we can deploy the latest technologies.

For this, you will have to:

  • Get to know Onyx One from A to Z.
  • Maintain and improve the system architecture.
  • Analyse and develop new requested functionalities with the product owner.
  • Guide junior developers and help take them forward to the next level.


You will work with:

  • Web technologies such as PHP, React, Node.js, Javascript / Typescript, HTML/CSS, MySQL, MongoDB
  • Camunda, a process orchestration platform
  • A SaaS platform hosted on AWS
  • Git versioning
  • The Atlassian stack (Jira, Confluence…)

You have a proven record in the use of

  • PHP (4+ years)
  • Design patterns
  • OOAD principles
  • Modern development architect/frameworks (eg. SOA, micro-services, serverless architecture, domain driven design…)
  • Having hands-on experience of React, Node.js, Express… is a big plus
  • You have a bachelor’s or master’s degree in IT or equivalent through experience
  • Your specialty is to develop user-friendly and intuitive software
  • You have a problem-solving attitude
  • You take initiative and you are a strong communicator
  • You speak and write English fluently


  • An attractive salary in accordance with your experience and with fringe benefits
  • The possibility to further develop yourself through courses…
  • A lot of room for responsibility and initiative
  • A modern environment in which you work with enthusiastic colleagues in a relaxed atmosphere and with self-managing teams

Are you our new Senior Web Developer / System Architect?
Respond quickly, we are eager to meet you!

Send your resume and cover letter to Katrijn at
Do you still have a question? Feel free to contact us at the number +32 9 269 80 21