Leaving Mozilla
I've never heard about rr <a href="http://rr-project.org/" rel="nofollow">http://rr-project.org/</a>), his tool to record program execution and debug it afterwards. The alleged 1.2x slowdown in execution is negligible. The ability to reverse in time is almost a nirvana. I'm sad I didn't have it when I used to program C++. Hope he succeeds in his new endeavor. We'd all win big.<p>Does anyone knows of similar tools for Python and in-browser Javascript?