Office Manager Aleida Sjardijn


Office Manager

Where Aleida joined us as office manager, she has left her mark in several fields: from customer support to our ultimate nice workplace (s). That requires quite a bit of flexibility. That is probably why we regularly hear her mumble ‘if things don’t go as it should, then it should be as it goes.’ 

Eigenaar Oprichter Boekhouder Gijs Rietveldt



Inline skating, kiting, motorcycling and climbing: all exhaust valves for sitting at his desk for hours on end. Because it is Bookie founder Gijs, who invented our product and develops the software. “People, can’t we simplify that?” Is not a crazy common question from someone who studied innovation management.

Boekhouder Jessica Willemse


Accountant Unit 2

As a real team player, Jessica ensures peace and attention at The Bookie. Goal-oriented is characteristic for her: she finds solutions in even the most challenging situations and asks questions until an answer is found. And if you ask her for help, you will almost always hear: “Yeah, no problem!”

Eigenaar Manager Mariangela De Lorenzo

Even though talking is her business, Mariangela likes to get things done. The reason she introduced ‘Mand‘ (meaning ‘Basket) internally and most know her as Mari, “because spelling your name a thousand times is not efficient at all.” Mari is ultimately responsible for all forms of Communication and the day-to-day affairs.


Backend Developer

Nicolás, our backend developer, develops on all fronts. This Colombian ‘Renaissance Man’ likes to be in nature or rescues local street dogs. Also one from the ‘don’t chat, but brush’ category that we love so much here, who regularly says ‘Breve’, which means something like: ‘Fine’ or ‘Will be okay’

Boekhouder Patrick Tang


Boekhouder Unit 2

Patrick is a real jack-of-all-trades and every so often learns a new set of skills that he then applies with love. That is why, in addition to being an accountant, he is also the second reader in our communication. In addition to being skillful with office humor, Patrick is also very precise. We also regularly hear “I’ll sort it out.”

Boekhouder Selin Dural


Accountant Unit 1

Selin always wants to know every little details. She is present early to be able to carry out structured checks and declarations. And don’t let the stunning looks betray you, this wizkid is a real numbers geek, who loves nothing more than numbers and graphs. That’s why we often hear her fantasize about ‘yummy annual figures’.

Boekhouder Simon Giesen


Accountant Unit 1

OG Simon, Original Bookie from the very beginning. Besides board games, this number master also loves puzzles: preferably financial puzzles and sorting out chores. Where there seem no solutions, he finds them. For example, how to fit more toasted sandwiches on the toaster, or he calculates that we grow on the basis of the fibonacci sequence.

Boekhouder Accountant Tim Methorst


Accountant Unit 2

Tim Methorst as Bookie has already compiled hundreds of annual reports and has taken care of thousands of tax returns. And if you count his jokes, “creating” is a full-time job for this man. He combines the two in an easy way to explain complex tax issues. ‘You learn by doing’ is one of his favorite sayings.


Frontend Developer

Our frontend developer Slava is master in all Javascript and ReAct languages. Throw this programmer a bug and he’ll fix some new features for you right away. Our skater has a real knack for languages. At least, he knows how to use Google Translate optimally to decipher the most complex word jokes and mislead us.

Office Manager Veerle Wormer


Customer Support

After a short internship, which she concluded with an ‘excellent’, we did not want to lose Veerle. This purebred Utrecht girl is a steady voice that you hear when you call our office. With her strong work ethic and good jokes, she is a great addition to our team. “No problem, I’ll check it out!” is a frequently heard comment.



Yesol, our Graphic & Digital Designer, who makes everything that little bit more fun and beautiful. In addition, she is a real K-pop star in dancing and she cannot be beat out of the gym. This perfectionist from Leiden occasionally treats us to her genuine Leiden ‘rrr’ and if you ask for her opinion, she always answers ‘Nice, but give it some Sol!’


Vacature Boekhouder Functie Solliciteren

Fullstack Developer

Vacature Developer Programmeur Boekhouder Functie Solliciteren

Intern bookkeeping

The Bookie is a young and ambitious accounting firm in the heart of Utrecht. Although our location is underground, our ambitions are sky high. And fortunately, because we’re going like a rocket. To ensure quality, we are always looking to expand our Bookie team.

Curious about what functions are available? View the vacancies and email us at