Hey 👋🏻 I am a software engineer with 20 years of experience. I specialize in web applications & APIs, developer tools, and open source. My passion is designing, building, & shipping products.

What I do

  • I build & ship software projects — web apps, developer tools, CLI apps, libraries, extensions; as sole developer, team member, or lead.
  • I write open source software such as HTTPie, a command-line HTTP client and one of the most popular Python projects on GitHub, or rrule.js, a popular TypeScript library for recurrence rules.
  • I have a background in startups — I have been involved in tech startup teams as senior engineer, lead developer, co-founder, and CTO; in San Francisco, London, Copenhagen, Barcelona, and Prague.

My experience

I have been working mostly in & on startups for over a decade now. Some have been VC-funded and some bootstrapped.

Subtle Apps

2005—2020, self-employed

Web app development consultancy. Consumer internet products with 300M+ page views.

Python Django JavaScript React


2016—2018, London, CTO & Co-Founder

Online interior design platform and marketplace. Backed by IKEA.

Python Django JavaScript React


2014—2015, San Francisco, Full-Stack Developer

The global video & music search engine.

Python Django JavaScript

Opbeat (acquired by Elastic)

2013—2014, Copenhagen, Senior Software Engineer

Application performance monitoring platform. Backed by FB and Instagram co-founders.

Python Django JavaScript


2012—2013, Copenhagen, CTO & Co-Founder

Intelligent scheduling platform for students and universities.

Python JavaScript


2010—2012, Copenhagen, CTO & Co-Founder

Web & mobile calendar and to-do app integrating school, personal and Facebook events.

Python JavaScript

What I studied

Continuous self-education guided by curiosity is the name of the game for me. I read books. Institutionally, the field of my study was Information Science:

  • Charles University in Prague, Czechia (bachelor’s degree)
  • University of Porto, Portugal (ERASMUS programme)
  • Royal School of Library and Information Science / University of Copenhagen, Denmark (Masters programme; incomplete)

What I open-sourced

Open source software development is in my DNA. I have been creating, maintaining, and contributing to various projects for 10+ years. Here are some of the things I have built:


Modern command-line HTTP client for the API era.



Recurrence rules for calendar dates as per the iCalendar RFC.

JavaScript TypeScript


Bitcoin trading bot with a real-time dashboard.

Python Tornado Django Postgres Redis JavaScript


Web-based music player for the cloud.

Python Tornado Redis MongoDB JavaScript


Utility for constructing raw HTTP requests on the command line.



Geotag photos based on your smartphone location history data.

Python Flask


Generates RSS feeds for podcast episodes from local audio files and expose both via a built-in web server.

Python Flask

How you can hire me

You can hire me for consulting work. I especially like to do shorter projects.

web apps MVPs interim CTO technical adviser Python Django JavaScript React Next.js
English Spanish Czech remote GMT+2

How to get in touch

Feel free to connect with me about consulting and volunteering opportunities. I am always open to providing feedback and advice to open source projects and early-stage startups.