[DigitalTerminal]

Also relevant is Google V8's Irregexp: https://blog.chromium.org/2009/02/irregexp-google-chromes-ne.... They claim 3x speedups.

[zamadatix]

https://github.com/google/re2 is probably a better matched library by Google since the post focuses on truly regular expressions and a lot of irregexp's design is around making the irregular part not as costly.