Regex Derivatives (Brzozowski Derivatives)
A Python sketch of a regex engine in less than 150 lines of code
Regex Derivatives (Brzozowski Derivatives) launched on March 7, 2023 with 103 votes, #541 of 5,007 launches that month and more than 95% of that year's launches. The site was still online in September 2026, 3 years on.
In plain words
Regex Derivatives is a minimal Python implementation of a regex engine built using Brzozowski derivatives, contained in fewer than 150 lines of code. It is designed for developers interested in understanding how regex engines work at a fundamental level or studying alternative parsing approaches. The project stands out for its extreme simplicity and brevity while still functioning as a working regex implementation.
written from the facts on this page · September 2026
From the sources
Brzozowski derivative python sketch. Contribute to c0stya/brzozowski development by creating an account on GitHub.
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