Curriculum Vitae

Name:      Mats Cronqvist
Phone      +46 72 7285755
E-mail:    mats@cronqvi.st
URL:       http://massema.net
Based in:  Stockholm, Sweden (GMT +1)
Languages: Fluent in Swedish and English, basic German
Passport:  EU (Swedish)
Education: Ph.D. in Physics
Professional Programming Experience: 32 years

Education
  1992: Ph.D. in Nuclear Physics from the University of Goteborg, Sweden
  1986: B.Sc. in Physics from the University of Goteborg, Sweden

  The subject of my Ph.D. thesis was: "Reaction Mechanisms in
  Intermediate Energy Heavy-Ion Collisions"

Skills
  Operating Systems:
    in daily use: linux (debian, ubuntu), osx
    mostly forgotten: VMS, irix, solaris, hp-ux, ultrix
  Programming languages:
    in daily use: Erlang, bash, learning Julia
    up to date: C, javascript
    mostly forgotten: BASIC, FORTRAN, pascal, various CERN languages
  Version Control Systems:
    in daily use: git
    mostly forgotten: cvs, clearcase, subversion
  Architectural Belief System:
    Decoupling, Distribution, Asynchronous Message Passing
  Always Installed:
    emacs >= 24, docker

Experience

  2017-present:
    Technical Director of 247.ai Sweden office. Managed ~15 developers.
    Did architecture, mostly regarding AWS services; S3, SQS, Glue, Presto.
    Did data analysis using Julia/Jupyter.

2016-2017: Architect at Campanja, Sweden
    Developing and architecting in a Campanja's system, mainly Erlang.
    Microservices running under kubernetes in AWS.

  2014-2016: Senior Architect, at Klarna, Sweden
    Protected the corporate revenue streams. My team made sure the cash cow
    system stayed well-functioning. We paid off technical debt, mainly through
    overload testing with intense profiling, judicious refactoring, and
    introducing sensible deployment and testing pipelines.

  2012-2013: Chief Architect, at Klarna, Sweden
    Responsible for the migration of the Klarna legacy business system from
    a monolithic Erlang application to system of loosely coupled services.
    Mostly successful, but the company decided to go down the Enterprise Java
    route.

  2011: Manager, Core Development, at Klarna, Sweden
    Managed a team of ~10 developers (mostly Erlang). Main task was to
    migrate functionality from the legacy system to services.

  2010: Manager, Live Operations, at Klarna, Sweden
    Managed the team that operated the Klarna business system. The teams
    tasks included system administration (Debian), application monitoring,
    upgrades of hardware and software.

  2007-2009: Senior Developer at Klarna (a.k.a. Kreditor), Sweden
    Implemented various parts of the Klarna business system (written in
    Erlang). Profiling and debugging.

  2003-2007: System Expert at Ericsson Telecom, Hungary
    Implemented a suite of profiling and troubleshooting tools for
    Erlang applications. Enabled us to identify numerous bottlenecks,
    significantly improving performance.
    In order to write the GUI for the profiler I invented and
    implemented a GTK binding for Erlang. The C-side is a daemon
    implementing the Erlang distribution protocol. Most of the C code
    is generated from the GTK header files.

  1997-2003: System expert at Ericsson Telecom, Sweden
    Implemented the first distributed version of our product. Allowed
    us to scale out the application on multiple CPUs.
    Invented the first serious Erlang troubleshooting tools. Still in
    heavy in-house use.

  1993-1997: Post Doctoral Researcher at Lawrence Berkeley Laboratory, CA, USA
    Wrote major pieces of the software for the E896 experiment at Brookhaven
    National Lab, including the on-line monitoring system, the event
    visualization, and most of the track reconstruction.
    Wrote most of the statistical analysis code for the TRANSPORT
    experiment at Lawrence Berkeley Lab.

  1986-1992: Graduate school at the University of Goteborg, Sweden
    Wrote many pieces of code for several experiments, mostly related to
    data analysis and visualization.
    Awarded a grant by the Sweden-America Foundation to spend a year at
    Michigan State University, MI, USA.
    Awarded a grant to develop a simple data analysis program for the
    Mac to be used in undergrad teaching lab. It was still in use when
    I graduated.

  1986: Software contractor
    Hired over summer break by the Nuclear Physics group at the
    University to develop a data visualization program for nuclear
    physics experiments. Hugely impressed everyone since it used 2-D
    graphics.

Open Source Programs
     At github.com/massemanet
      gtknode - an Erlang GTK binding
      inotify - an Erlang binding to the Linux inotify API
      redbug - a tracing debugger for Erlang
      ...

     At github.com/marijnh/CodeMirror/tree/master/mode/erlang
      An erlang mode for CodeMirror (a code editor javascript component)

     Maintains distel (Erlang-Emacs interface)