ninja

I worked on a project where lexing speed was of concern. Because it was C++ I didn't have the easy option of reaching for regexes so I instead wrote a hand-rolled lexer as suggested in the post. But later I found a tool, re2c, where you write regular expressions in your source code and it expands them out to a fast parser using every last trick (gotos and lookup tables, see an example of the generated code here[1]). The result had the delightful and rare property where the final code was both higher-level (regexes are a succinct way of expressing lexing) and faster than the lower-level hand-rolled code. https://github.com/ninja-build/ninja/blob/3082aa69b7be2a2a06...

Which cmake generator was used? The links seem to be dead, so it isn't clear. I mention this because I'm using cmake for a current project, and backend choice seems to be somewhat important. I found a noticeable improvement when I switched from using a make-based backend (NMake on Windows, GNU Make on OS X and Linux) to the Ninja one (see https://github.com/ninja-build/ninja). Based on my notes from the time, full build times were basically unaffected on a per-core basisi - but no-op builds were markedly quicker. My notes don't say anything about builds where only one or two files were changed, but my recollection is that that case was noticeably improved as well. For whatever it's worth, figures from my notepad from a few months ago. Apologies for the scrappiness; these were just brief notes I took at the time, all rather random, just to