Felix Mulder

Computer Science Engineer


Avenue de la Chablière 35b
1004, Lausanne



16 Oct, 1990


Swedish native
English full professional
Japanese elementary


2011 - 2016 Master of Science Computer Science Engineering Lund University, Sweden
  • Algorithms, Data structures and Complexity
  • Optimizing Compilers
  • Real-time Programming and Concurrency
  • Operating Systems
2008 - 2009 Foreign Exchange Year Japanese High School Ikubunkan Yumei Gakuen, Tokyo


09.2016-Present École Polytechnique Fédérale de Lausanne Compiler Engineer, Release Mgr for the Scala 3 compiler - Dotty Lausanne, Switzerland

Working on Dotty, a next generation compiler for Scala. The focus is mainly on simplification. We remove extraneous syntax, and try to boil down Scala’s types into a smaller set of more fundamental constructors. The theory behind these constructors is researched in DOT, a calculus for dependent object types.

I reimplemented error handling to allow for amazing error messages that tell you what went wrong, offer fixes and give concrete examples using your own code as example.

I wrote a documentation compiler from scratch - and enabled it to be much more than just creating API reference like in the previous generation. It is now a full-blown static site generator, where you can cross reference between code and documentation; which makes sure that you both cater to your users and contributors - without duplication.

As release manager for the project, I am also responsible for developing and implementing a release strategy, guiding our team towards the MVP and keeping the community informed via talks and workshops.

05.2017-Present Google Summer of Code Mentor for Scala Organization

Mentoring student on improvements to documentation compiler. Including type-safe templating engine and compiled documentation - making sure the code examples in your documentation actually compile, ensuring that your examples are always up to date with the released code.

05-08.2016 Google Summer of Code Scala Organization

Implementing the next generation documentation tool, alias dottydoc, for Scala. Improvements over the old scaladoc include a full Scala stack from runnable binary to client JavaScript using Scala.js

02-05.2016 École Polytechnique Fédérale de Lausanne Research Fellow, Programming Methods Laboratory (LAMP) Lausanne, Switzerland

Working on the next generation Scala compiler - dotty - and the tooling surrounding it.

The majority of the work consisted of identifying analyzing and fixing issues in the compiler. Major contributions include partial evaluation of statically known function results, implementing a REPL based on Ammonite and laying the groundwork for the next generation documentation tool dottydoc.

2014 - 2016 Axis Communications AB Student Software Engineer, Core Technologies Lund, Sweden

Master's Thesis: Image Processing Across Multiple Interconnected System-on-Chips

Developed a Linux kernel performance indexing framework, measuring relative performance difference in key parts of the kernel using Python.

Implemented reference counting in Axis's video memory driver for debug purposes. It identified a potential deadlock on its first day of service.

Researched and implemented GPU use cases for Axis's embedded systems using C and OpenGLES.

Built a system for cataloging and maintaining test data. Making more than a terabyte of data not previously cataloged, searchable.

2012 - 2015 Sole Proprietor Software Engineer and Consultant Lund, Sweden

Developed an ordering system and API for Malmö's largest taxi company using Scala, Akka and PostgreSQL. Enabling users to order cabs and track their location in real time.

Developed the second version of the taxi company's iOS app.

Project manager for iOS & Android development on taxi apps.

2012 - 2015 Lund University: Computer Sc. Dept. Teacher's Assistant and Lab Manager Lund, Sweden

Data Structures, Abstraction and Design using Java

Programming and Databases

Computer Organization, taught students the basics of computer architecture, assembly and real time systems.

2012 - 2013 Menmo Software Developer, Web Applications & Services Malmö, Sweden

Developed the companion app and backend for a coffee bar and startup incubator. Enabling booking of meeting rooms, ordering products from the bar, Wi-Fi access as well as invoicing.

Webmaster and developer for the daily newspaper Skånska Dagbladet


Programming Languages

Scala, Java, C, Python, C++14, Haskell, JavaScript, node.js

Other Skills

Linux, OS X, SQL/NoSQL, Akka, Kafka, Reactive Programming, Redis, Spark, TCP/IP, Scrum, git, Chef, TDD, RestAPIs, Angular.js, Leadership, Teamwork


  • Compiler Team Member of dotty
  • Contributor to Scala: key contributor to the 2.12 Scaladocs tool
    • Getting into Scaladoc Development featured on
  • Blog on CS topics -
  • Contributor to Play Framework
  • Contributor to Slick
  • Contributor to Shine: fast fixed-point MP3 encoding
  • Maintainer of unofficial Lund Computer Science repository
  • Implemented the TCP/IP stack on the ETRAX server using C++
  • Founder of fest-app a small social network application for events


  • Competed in Swedish Espresso Brewing Championship and placed 8th.
  • Worked as chief of QA, machine engineer and group leader for the coffee tents at the university carnival, Lundakarnevalen. The carnival involves 6 000 students and attracts over 400 000 visitors


Available upon request