Since one of the mentioned improvements is performance of the builtin regular expression library... for anyone curious, there's a drop-in replacement, re2, that

Since one of the mentioned improvements is performance of the builtin regular expression library... for anyone curious, there's a drop-in replacement, re2, that leverages a Google library to provide linear time guarantees for arbitrarily complex or user-provided regexes. (You lose lookahead assertions, but most use cases for them can just be handled in pre- or post-processing.) It's an incredibly handy tool that lets us confidently use complex regexes in production. https://pypi.python.org/pypi/re2/ https://pypi.python.org/pypi/re2/ https://github.com/google/re2/wiki/WhyRE2 https://github.com/google/re2/wiki/WhyRE2 > RE2 was designed and implemented with an explicit goal of being able to handle regular expressions from untrusted users without risk. One of its primary guarantees is that the match time is linear in the length of the input string. It was also written with production concerns in mind: the parser, the compiler and the execution engines limit their memory usage by working within a configurable budget – failing gracefully when exhausted – and they avoid stack overflow by eschewing recursion. Really interesting articles in the second link detailing how this works!