AI-assisted rewrite of chardet boosts performance by 48x in 5 days, but sparks open-source license controversy

The Python character encoding detection library chardet recently released version 7.0, rewritten by maintainer Dan Blanchard using AI programming tool Claude Code in just 5 days. The new version increases performance by up to 48x and changes the license from strict LGPL to permissive MIT, allowing closed-source commercial use.

This change triggered strong protests from original author Mark Pilgrim, who argues the new version is illegal reauthorization and fails clean room reverse engineering standards, demanding restoration of LGPL. Blanchard defends with JPlag data showing only 1.29% similarity to the old version, but questions about AI training data including original code and human intervention's impact on independence remain legal gray areas.