Allround Developer

  • Job title Allround Developer
  • Location Apeldoorn

Koolen Industries Solar

Your job as Allround Developer

What do you need

What's in it for you


Are you allround develer with affinity (and ambition) for data, and would you like to make the world a greener place in a fast growing company?


Koolen Industries was founded in 2019 by entrepreneur and investor Kees Koolen (former founder and CEO of and early investor in Uber) with the aim of achieving a rapid transition to clean, renewable energy. The focus of the scale-up Koolen Industries Solar (KIS) is on generating and making sustainable energy available.


Besides our AI Specialist, you will be the first Developer within the KIS group. Allround because initially, a variety of projects can be taken on. The intention is for you to eventually focus on data (engineering).

A week of the allround developer

Monday: Consultation with the recruitment team about their wishes for the ‘Working at’ site. For this, you need to develop connections in PHP between the HR system and the WordPress website of Koolen Industries Solar. In the afternoon, you work together with the AI team to implement the built sales agent on the Umbraco (.NET) website of the company Bongo Solar.

Tuesday: Uninterrupted coding at home. The new AI project you are working on is almost ready to be tested. Super!

Wednesday: At the office, you discuss a possible price comparison tool with the Head of Marketing. After gathering the necessary information from the various companies in the group, you proceed to create a functional design. In the afternoon, you have a meeting with recruitment to discuss the vacancy for a new Developer.

Thursday: Today you have a brainstorming session with an AWS consultant to discuss how we will set up the cloud.

Friday: The role is for a minimum of 32 hours per week. This could very well be your day off. Or a work from home day.


  • Minimum HBO level of education, preferably in IT.
  • Experience in database management in MySQL.
  • Programming experience with PHP and/or .NET.
  • Ambition towards Data Engineering (Python).
  • Good command of the English language.
  • Independent, proactive and results-oriented.


  • A full-time salary between €3,750 and €5,000 gross per month (depending on your work experience and knowledge).
  • Various growth opportunities within a fast-growing and innovative company.
  • Location Apeldoorn and if practical, Schiedam. (in addition, hybrid working is possible).




Marcel de Jong 020 6120081

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