Stefan Haller
Data Scientist
Berlin, Germany
Summary
🤩
Rockstar🎓
Top SchoolStefan Haller is a Berlin-based Data Scientist with 15 years of experience building scalable ML pipelines and serverless architectures, currently developing industrial AI solutions at Machine Learning Reply. He combines hands-on data engineering on AWS with applied research in predictive maintenance and inventory optimization for automotive and utility clients. His background spans NLP and deep learning — from prototyping an automated grading and chatbot system at the University of Twente to production-focused preprocessing of large, heterogeneous datasets. Stefan also contributes to open-source tooling, improving the UI/UX of the popular lazygit terminal Git client with enhancements like scrollable panels and richer file-change displays. With dual studies in energy economics and computer science and an MS in Business Information Technology/Data Science, he brings both domain insight and technical rigor to cross-functional teams. Pragmatic and detail-oriented, he excels at turning complex data flows into reliable, efficient ML products.
15 years of coding experience
Bachelor of Science - BS, Computer Science, Bachelor of Science - BS, Computer Science at Universität UlmBachelor of Science - BS, Energiewirtschaft, Bachelor of Science - BS, Energiewirtschaft at Fachhochschule BiberachMaster of Science - MS, Business Information Technology/Data Science, Master of Science - MS, Business Information Technology/Data Science at Universiteit Twente
German, English
Github Skills (6)
user-interface10
front-end-development10
go9
user-experience7
exp7
version-control6
Programming languages (11)
Github contributions (5)
jesseduffield/lazygit
Jan 2023 - Jul 2026
simple terminal UI for git commands
Role in this project:
Full-stack Developer
Full-stack DeveloperContributions:5 releases, 726 reviews, 926 PRs in 3 years 6 months
Contributions summary:Stefan primarily contributed to the user interface of the lazygit application, with changes focused on improving and streamlining the user experience. Their work included enhancements to keybinding menus, improved presentation of file information in the UI (e.g., showing the number of lines changed), and improvements to the layout of the UI, as demonstrated by the addition of scrollable panels. The user also modified and extended functionality for applying custom commands.
gitcommandterminal-uicliterminal
stefanhaller/vscode-gitk-blame
Oct 2020 - Apr 2026
Contributions:1 release, 1 push, 4 branches in 5 years 6 months
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.