Gregoire Lejeune
Founding Engineer at Phacet
Issy-les-Moulineaux, Ile-de-France
Summary
👤
Senior🎓
Top SchoolGregoire Lejeune is a founding engineer and seasoned software leader based in Issy-les-Moulineaux with 16 years of hands-on engineering and product experience and a broader 20-year background spanning science and computer science. He has a strong track record founding and scaling startups (G-Corp, BotsUnit) and leading engineering and CTO roles across fintech, SaaS, and performance startups before most recently joining Phacet. Gregoire bridges deep technical craftsmanship—demonstrated by back-end contributions to projects like a Ruby-Graphviz mirror—with product and managerial strengths developed as a senior engineering manager and founder. He pairs practical systems design and delivery experience from companies like Dataiku and Fasterize with formal executive training in cybersecurity from EGE. Known for shipping pragmatic solutions, he often surfaces useful examples and tooling to help teams visualize and reason about complex systems. Colleagues would describe him as adaptable, scientifically minded, and comfortable toggling between code, architecture, and business strategy.
16 years of coding experience
24 years of employment as a software developer
DEA Chimie informatique et théorique, DEA Chimie informatique et théorique at University of StrasbourgExecutive MBA, Management de la Cybersécurité et Gouvernance des systèmes d'Information, Cybersécurité, Executive MBA, Management de la Cybersécurité et Gouvernance des systèmes d'Information, Cybersécurité at Ecole de Guerre Economique – EGE
English
Stackoverflow
854reputation
100kreached
13answers
1question
graphviz
top-5%
Github Skills (11)
graph-visualization10
ruby10
graphviz9
graph6
bots6
graph-layout6
irc6
dot6
layout6
family-tree6
genealogy6
Programming languages (12)
Github contributions (5)
glejeune/Ruby-Graphviz
Aug 2009 - Mar 2020
[MIRROR] Ruby interface to the GraphViz graphing tool
Role in this project:
Back-end Developer
Back-end DeveloperContributions:360 commits, 18 PRs, 32 pushes in 10 years 8 months
Contributions summary:Gregoire's commits primarily focus on adding example code that uses the ruby-graphviz library to generate various graph visualizations. The contributions demonstrate the user's understanding of how to leverage the library for creating and manipulating graph structures. The work involved adding new sample files and modifying existing ones to showcase different graph features and functionalities.
graphvizrubygraphing
glejeune/node-graphviz
Sep 2010 - Apr 2019
Node.js interface to the GraphViz graphing tool
Contributions:51 commits, 9 PRs, 13 pushes in 8 years 8 months
node-jsjstreenodejsgraph-drawinggraph
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.