Hi, I’m Jonathan! I’m a software developer based in Dresden, Germany. I work mainly in web development as a fullstack developer, specialising in the frontend development. I mostly use TypeScript/JavaScript, as well as Python and occasionally Rust.

If you’re interested in working with me, email me at jonathan.frere@example.com.gmail.com , or see my contact page. Alternatively, you can talk to my employer, Esveo GmbH, directly — we’re always interested in new projects to work on!

Blog Post Highlight Reel

• This Overly Long Variable Name Could Have Been a Comment — a short recent post about balancing comments and verbose naming conventions.
• Why are Jujutsu’s ID Prefixes So Short? — a deep dive into how one part of the JJ VCS works.
• Why Test? — trying to put my testing philosophy into words.
• New Disposable APIs in Javascript — exploring Explicit Resource Management in JS, including some new patterns that it enables.

Talks I’ve Given

• Dev Day, Dresden Germany, April 2025 — Is There Life After Git?
• c’t <webdev>, Cologne, Germany, Nov 2024 — Cleaning Up After Yourself (blog post)
• NodeConfEU, Waterford, Ireland, Nov 2024 — Cleaning Up After Yourself (blog post, video)
• EnterJS, Mainz, Germany, May 2024 — Signal and Noise: What We Learned Using Signals for the Last Year
• Dev Day, Dresden, Germany, April 2024 — Playwright: Das Beste aus dem Dramatiker herausholen (video) (N.B. German)
• c’t <webdev>, Cologne, Germany, Nov 2023 — Signal and Noise: What We Learned From Using Signals for the Last Year

Tools and Utilities

• Codenames Duet Key Cards — an online tool for generating key cards for playing Codenames Duet with a different Codenames box. You can also view the source code.