About me

My name is Jan Ouwens and I’m a developer from the Netherlands. Currently, I work for Codestar. I do a bunch of things:

Projects

  • EqualsVerifier - [site] [github] [java]
    A tool to make rigourously testing Java’s equals and hashCode methods a one-liner
  • Foobal - [site] [github] [scala]
    A program I use to predict the outcome of soccer matches, so that I can participate in the family pool without needing to learn about the actual sport
  • ReminderMail - [site] [github] [kotlin]
    A small Android app that makes it easy to quickly send mails to yourself
  • ComposeKey - [site] [github] [scala]
    A bundle of text-expansion snippets for Alfred that mimic the behaviour of Linux’s compose key
  • vim-reversal - [github] [vimscript]
    A colorscheme for Vim that highlights identifiers and de-emphasizes keywords, so you can easily see what’s important in your code

Talks

  • Don’t hack the platform? ☠️💣💥 - [github]
    A funny anthology of tricks and hacks for the JVM.
  • Not all equals methods are created equal - [github]
    How to write a good equals method, and to test it with EqualsVerifier.
  • Growing a DSL for financial calculations
    The story of how my colleague and I ‘discovered’ a Scala DSL for writing complex mortgage calculations.
    • 7 October 2016, HBO-ICT Job & Student event Rotterdam - [event]
    • 4 May 2016, Typelevel Summit Oslo - [event] [video]
    • 13 April 2016, Appril Festival - [event]
    • 31 March 2016, Brabant Scala Meetup - [event]
    • 24 March 2016, Codestar Launch Event - [event] [partial video]
    • 23 November 2015, Scala Utrecht Meetup
  • Scala
    A quick overview of Scala language features, intended for Java developers.
    • 11 June 2014, Sogeti - [video]

Writings

  • 2011 - present, tr ouwens - [site] [english]
    my tech blog
  • My publications in the Dutch Java Magazine
    • October 2018, Lees dit niet! ☠️💣💥 - [dutch]
    • February 2018, Selenium is leuk met ScalaTest - [site] [dutch]
    • April 2016, Een DSL kweken - [site] [dutch]
    • June 2015, Grip op je buildproces met Gradle (met Hanno Embregts) - [site] [dutch]
  • 2009 - 2012, Brief en leed - [site] [dutch]
    a funny letter-writing blog I did with my friend Ralf
  • January 2008, Voorstel voor een methode voor de kwantitatieve analyse en vergelijking van beeldverhalen - [PDF] [dutch]
    a way too in-depth survey of Asterix jokes
  • August 2005, The Performance of Wireless MPEG-2 Video Streaming - [PDF] [english]
    my Master’s Thesis