Jelmer Vernooij
Software Engineer at Cloudflare
Stony Stratford, England, United Kingdom
Summary
🤩
Rockstar🎓
Top SchoolJelmer Vernooij is a veteran software engineer with over five decades of experience, currently working at Cloudflare and contributing at evroc. He combines deep backend and security expertise—evident from contributions to Heimdal Kerberos, aiohttp security fixes, and production-grade refactors—with full‑stack localization work on projects like Isso. A former principal SRE and staff engineer at companies including Google, Aiven, and Cognite, he excels at hardening distributed systems and improving test suites and compatibility across libraries. His open-source history shows pragmatic improvements that prioritize usability, such as adding an index view and submodule support to the Klaus Git web viewer and making PKI functions reusable in Heimdal. Based in Stony Stratford, he pairs low-level systems knowledge with a knack for polishing developer-facing tools and documentation. Colleagues can expect a steady technical leader who quietly fixes edge cases that prevent systems from failing in production.
52 years of coding experience
13 years of employment as a software developer
University of TwenteDe VlaswiekComputer Science, Computer Science at Utrecht UniversityHigh School, High School at Christelijk Gymnasium Utrecht
English, Dutch
Stackoverflow
2,451reputation
70kreached
112answers
1question
Github Skills (39)
git10
zero-configuration10
pytest10
python10
kerberos10
http10
internationalization10
c-programming10
c1110
c1710
localization10
pki10
co10
aiohttp10
werkzeug9
Programming languages (38)
Github contributions (5)
isso-comments/isso
Jun 2014 - Nov 2022
a Disqus alternative
Role in this project:
Full-stack Developer
Full-stack DeveloperContributions:2 releases, 72 reviews, 285 commits in 8 years 7 months
Contributions summary:Jelmer primarily contributed to the localization of the Isso commenting system, adding Dutch, Danish, and European Portuguese translations. They also fixed bugs and improved the existing codebase, including resolving flake8 errors and addressing compatibility issues with newer versions of Werkzeug. Furthermore, they made improvements to the documentation, contributing to a more user-friendly experience. The user's work touched both frontend and backend files, indicating a full-stack development focus.
reactdisqusjavascriptsqlite3typescript
jonashaag/klaus
Nov 2015 - Jan 2023
docker run klaus / pip install klaus — the first Git web viewer that Just Works™.
Role in this project:Back-end Developer
Back-end DeveloperContributions:4 reviews, 35 commits, 37 PRs in 7 years 3 months
Contributions summary:Jelmer primarily contributed to enhancing the Git web viewer "klaus" by implementing new features and resolving issues. They introduced an "index" page to display commit history and README.md content, improving the user interface. Further, the user added support for gitweb clone URLs and submodule viewing capabilities. The user also improved the project by refactoring the code and fixing various compatibility issues.
pythonpipdockergit-webdocker-run
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