About
Senior .NET, Azure and AI engineer in Luxembourg. Lex is one of three systems built the same way.
I build systems that have to be right rather than plausible: regulated platforms where an answer has to carry its source, its date, and a way to check it.
Soufien Hajji, senior .NET, Azure and AI engineer, based in Luxembourg. Nine years across telecoms, rail, investment banking and asset management, most of it on systems where being wrong is expensive: front-office trading platforms, regulatory-capital reporting, and the agentic AI layer on top of it.
Lex is a personal project, unaffiliated with any publisher or public body. It is built the way I build professionally, which is the reason it exists: the pipeline is deterministic, the claims are testable, and the parts that cannot be verified say so instead of guessing.
Three things, built the same way
Point-in-time Luxembourg law and ten EU acts: 1,409 works as 4,705 dated versions, a public MCP endpoint, open datasets, and a signed index whose stamp commits to a digest of its own content. The hard part was never the AI; it was that a law has no single text, only a text per date. The decision that shaped it, and what it cost →
Ask about my experience or my code, drop in a job advert to see how it matches, or run a mock interview. Grounded in a corpus of my own work, and it cites where each answer came from.
An AI co-pilot for photovoltaic prospecting in Luxembourg: which roofs and car parks qualify, the tariffs and grants that apply, and the law behind the answer. Every claim is cited, and it declines rather than guessing.
How I work, if that is what you are here for
The clearest evidence is not a CV. It is the decisions page, which states each choice, the alternative it was taken over, and the bill; the coverage page, which exists to say what this service does not hold; and the verification page, which tells you how to check the answers without trusting me. A system that cannot say what it lacks is not finished.
How this was built → · Why it is built this way → · GitHub →