I'm Kevin van Zonneveld (@kvz). In a previous life I worked at a hosting company where I learned about code, distributed systems, and networks. Halfway I became their R&D lead and among things architected their cloud offering. In evening hours I co-founded Transloadit, a file uploading and encoding service for developers.

I run that company to this day with 10 teammates, spread across the world. I will happily bore you to death about family life, open/innovative technology, automation, dev tools, unix, all kinds of independent music, (watching, practicing, teaching) kickboxing, woodworking, Amsterdam, craft beer, collecting retro games, and sci-fi.

I started this blog in 2007 and always tried to share what I just figured out, hoping to help my future self, others running into the same things, and most importantly to improve my understanding through your feedback. Although with a young family and company I don't publish too much here lately.


I've stopped doing consultancy in 2015 to focus entirely on Transloadit. Before that I ran consultancy from my private company Bracebit, and it also owns 50% of Transloadit. Here are its details:

Bracebit B.V.
The Netherlands

Founded on: November 15th, 2012
Commercial Register (KvK): 56496346
VAT-ID: NL-852154446B01
IBAN: NL29 FVLB 0226 9059 69
Director: Kevin van Zonneveld


Here are a few things I've been up to over the past years

2017 - 2023

With our team growing I spend less time getting my hands dirty and focus more on growing Transloadit and enabling my fellow Transloadians.


Learned about RethinkDB, NixOS, React Native and created prototypes using these technologies.

Started reading up on Kubernetes and Machine Learning.

Created new websites for BASH3 Boilerplate, Locutus, Frey, Transloadify and Lanyon.

Open sourced Uppy, Frey, Fakefile, Lanyon, json2hcl, and contributed to postcss-svg, and NixOS.


Focussed on growing Transloadit's back-end and business. Writing blog posts, sponsoring conferences, and automating the hell out of our infra so we can sustain growth without linearly ramping up costs.

Tried to raise awareness for tus and got it to 1.0.

Open sourced node-depurar, environmental, jekyll-fix-titlecase, ratestate, riak-formation, sledge, tosip, and contributed to docker compose, flat, ruby_route_53, lipsync, terraform, terraform, packer and vagrant.


Quit my job at true.nl so I could focus on Transloadit, consultancy, and open source.

Consulted for corporations like Dutch newspaper NRC.nl where I rebuilt their failing system for digital newspaper distribution with subscription handling for iOS apps and its high availability infra; and AECOM.com, the #1 global construction company, where I advised on IaC (Infrastructure as Code).

Open sourced metriks.io, ratestate, airbud, baseamp, environmental, riak-formation, and contributed to fig and async.


Launched tus.io with Tim Koschützki and Felix Geisendörfer. It's an effort to write an open protocol & implementations for resumable file uploads across all platforms (HTML5, iOS, Android, Go, Node.js, Ruby, etc) so that all components will in the future be able to send big files following the same basic principles.

As friends bootstrapped from a basement to become the largest Amsterdam-East kickboxing gym, I helped out where I could. For three years I gave (kick)boxing classes to 10-40 adults.

Open sourced ochtra, nsfailover, bash3boilerplate, on-the-githubs and cronlock.


Founded Bracebit, my own company to do freelance consultancy after having been employed for 8 years.


Open sourced many CakePHP plugins. Most known are EventCache and a plugin for creating REST services.

Gave a few talks on them.


I co-founded Transloadit with Tim Koschützki and Felix Geisendörfer. The world's first commercial Node.js company. We handle file uploading, converting and storing. We're bootstrapped and ramen profitable as of March 1st, 2012, and are still growing.

I made a modest contribution to Node.js.


Open sourced System_Daemon that let's you turn PHP scripts into Linux daemons, effectively allowing you to write networked servers in PHP. We were able to get this to run without memory leaks or garbage collection issues, although that proved quite a challenge. It was adopted by PEAR which meant dealing with rigid coding standards, documentation requirements, a CVS(!) server, and peer-critique. Many things a first for me.

Of course nowadays there are better ways to achieve this, if you really have to anyway.


Open sourced php.js which offers PHP functions in Javascript. At first just to bridge the gap between browser and servercode as I needed compatible base64 and urlencoding functions. After sharing on my blog the project gained traction and it remained fun to see if we could port more functions, effectively allowing you to run PHP code in the browser or Node.js. In 5 years over 600 developers wrote over 400 functions and the project was forked 467 times. I shed just as many tears over mis-use of this project. I tried to right some wrongs by doing a complete overhaul in 2016: the project is now known as Locutus, supports showcasing any language->js and is very clearly geared towards education.


I started kevin.vanzonneveld.net, my personal blog that was later migrated over to kvz.io. In 2010 I celebrated its success by giving free beer to Switzerland.


I started working for true.nl, a hosting provider based in Amsterdam. Specializing in hosting big web sites, True needed to nail things like: scalability, performance, security and always be on the lookout for cool new technology.

In the 8 years I worked for True I have:

  • Had the lead in research & development, introducing many cool open source projects into the company and streamlining the development process by use of Git, frameworks, tests, CI, rolling deploys, etc.
  • Consulted clients in building large scale fault-tolerant hosting solutions
  • Architected & implemented countless high-availability Linux clusters
  • Designed their cloud offering
  • Been trying to automate virtually every business/tech process within the company


At college they were running their first year of computer science and there weren't enough teachers. I was given the opportunity to give classes on what I had learned at Ineas, and we built a college community online together - in return I got my grades. This was extremely exciting initially but after completion, it appeared to me I should have picked a more mature college, and was left with the feeling that I still had much to learn, but it wasn't going to be at that particular place. I put my energy elsewhere and enjoyed the fraternity life way too much to do anything interesting with computers beyond building a website or two for them.


Got my hands on Visual Basic 6 and many games such as a Pacman reincarnation. My biggest project was networked software to control school PCs (student login, track/charge prints, limit web & machine access) so they would not have to license Novell. I got to skip computer-class but the project was never deployed at full scale, which was a big disappointment, but in hindsight, probably for the best :smile:


Started working for Ineas. The first online insurer in Europe. This is where I first learned how to create real world value with programming. I made an online version of the European Car Accident Insurance Claim Form. Inease being a pioneer we faced many technical (no php, ruby, or node), legal (signatures?) and marketing (how do we get people to trust online insurances) challenges.


Joined one of the first Dutch e-mail groups with developers that would mentor me into building slightly more advanced programs than what I had been up to.


Devoured a QBasic book with my father, and wrote my first computer program: an assistant in buying the best kind of fireworks.


I was born in a small village in The Netherlands :tada: