Leon Timmermans
Senior Software Engineer at Perl 5 Porters
Utrecht, Netherlands
Summary
🤩
Rockstar🎓
Top SchoolLeon Timmermans is a Senior Software Engineer with 17 years of experience building low-level, reliable infrastructure across networking, asynchronous I/O, Linux system programming, security, and distributed systems. He brings deep C, C++ and Perl expertise (and growing interest in Rust) to performance optimization, applied cryptography and robust build systems, often preferring projects where long-term stability matters. A prolific open-source maintainer—authoring 70+ CPAN modules and contributing to high-profile projects like Dist::Zilla and the Rakudo compiler—he excels at tooling that boosts team productivity and testability. Formerly trained as a life scientist, he applies the same analytical rigor and pattern-recognition strengths from biology to complex software problems. Comfortable in both startup and large cooperative codebases, he thrives on taking responsibility for hard, system-level pieces that other teams depend on. Based in Utrecht, he is active in Perl 5 maintenance and known for pragmatic, safety-first architectures that make the easy path the correct one.
17 years of coding experience
8 years of employment as a software developer
Molecular and Cellular Life Sciences, Molecular and Cellular Life Sciences at Utrecht UniversityBSc Molecular Life Sciences, BSc Molecular Life Sciences at Wageningen University & Research
English, Dutch
Stackoverflow
30,113reputation
4.5mreached
328answers
0questions
trim
top-1%
regex
top-5%
testing
top-5%
networking
top-5%
perl
top-1%
integer
top-5%
Github Skills (27)
moarvm10
back-end-development10
compiler-development10
testing10
perl10
cpan10
raku10
trim10
dependency-management9
networking9
nqp9
regex9
build-automation9
prototypes9
integer9
Programming languages (16)
Github contributions (5)
rjbs/Dist-Zilla
Mar 2011 - Dec 2018
scary tools for building CPAN distributions
Role in this project:
Back-end Developer
Back-end DeveloperContributions:8 commits, 4 PRs, 11 comments in 7 years 10 months
Contributions summary:Leon primarily contributed to the Dist::Zilla project by adding features and modifying existing ones related to the build and testing processes for CPAN distributions. They refactored code, composed roles to streamline the build process, and added options for command-line tools like `dzil listdeps` and `dzil test` to improve dependency management and testing verbosity. Additionally, the user integrated SPDX expressions and the HARNESS_OPTIONS environment variable to enhance metadata and test execution.
distributionscpan
rakudo/rakudo
Jul 2015 - Jan 2023
🦋 Rakudo – Raku on MoarVM, JVM, and JS
Role in this project:Back-end Developer
Back-end DeveloperContributions:6 reviews, 20 commits, 17 PRs in 7 years 6 months
Contributions summary:Leon primarily contributed to the Rakudo Raku compiler, focusing on core functionality. Their work included improving the `Proc` and `Proc::Async` modules, enhancing exit code and signal handling. Additionally, the user modified the build process and debugger to handle new language features, and made changes to the TAP testing framework.
rakudorakujavascriptmoarvmjvm
Find and Hire Top DevelopersWe’ve analyzed the programming source code of over 60 million software developers on GitHub and scored them by 50,000 skills. Sign-up on Prog,AI to search for software developers.