Rafał Leśniak
Senior Frontend Developer at DUOLIFE
Hanover, Lower Saxony, Poland
Summary
👤
Senior🎓
Top SchoolRafał Leśniak is a Senior Frontend Developer with 22 years of experience building robust web applications from UI to backend integrations, currently based in Hanover, Poland. He specializes in React, Next.js and TypeScript, with deep practical knowledge of Docker and Kubernetes from running production workloads and developer tooling. Rafał’s background spans full-stack roles and entrepreneurship, having led development, sales support and production management at his own firm while also delivering scalable frontends at Duolife. He contributes to open-source projects as a backend maintainer as well, fixing memory leaks and hardening network daemons, which reflects a pragmatic attention to stability beyond the browser. Known for shipping pragmatic solutions in Agile teams, he pairs front-end craftsmanship with systems-level problem solving.
23 years of coding experience
10 years of employment as a software developer
Inżynier (Inż.), Computer Science, Inżynier (Inż.), Computer Science at Wyższa Szkoła Zarządzania i Bankowości
Github Skills (5)
c1710
memory-management10
c1110
vpn10
networking10
Programming languages (4)
Github contributions (5)
gsliepen/tinc
Jun 2015 - May 2017
a VPN daemon
Role in this project:
Back-end Developer
Back-end DeveloperContributions:12 commits, 11 PRs, 3 comments in 1 year 10 months
Contributions summary:Rafał primarily focused on fixing memory leaks, edge handling, and improving overall stability of the VPN daemon. Their contributions included cleaning up allocated memory, addressing issues related to local addresses, and preventing potential memory access errors. Additionally, they improved the system by removing unnecessary code and ensuring data integrity across different versions.
vpn
thorkill/eresi
Aug 2003 - Sep 2019
The ERESI Reverse Engineering Software Interface
Contributions:326 commits, 5 PRs, 8 pushes in 16 years 3 months
reverse-engineering
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