Various benchmarks to have feedback about PostCSS perfomance.
All results below was runned on node 7.10.0, Fedora 25, Intel Core i7-6500U, 8 GB RAM and SSD:
Compare CSS processors for parsings, nested rules, mixins, variables and math:
Stylis: 30 ms (1.6 times faster)
PostCSS: 49 ms
Rework: 67 ms (1.4 times slower)
libsass: 100 ms (2.1 times slower)
Stylus: 169 ms (3.4 times slower)
Less: 171 ms (3.5 times slower)
Stylecow: 298 ms (6.1 times slower)
Ruby Sass: 1779 ms (36.4 times slower)
To get results on your environment:
npm install
bundle install
npm test preprocessors
Compare CSS parsers written on JS:
CSSTree: 6 ms (4.8 times faster)
Stylis: 12 ms (2.3 times faster)
PostCSS: 29 ms
CSSOM: 29 ms (1.0 times slower)
Mensch: 31 ms (1.1 times slower)
Rework: 51 ms (1.8 times slower)
PostCSS Full: 72 ms (2.5 times slower)
Gonzales: 113 ms (3.9 times slower)
Stylecow: 143 ms (5.0 times slower)
Gonzales PE: 156 ms (5.4 times slower)
ParserLib: 344 ms (11.9 times slower)
To get results on your environment:
npm install
npm test parsers
Compare vendor prefixes tools:
Stylis: 15 ms (3.5 times faster)
Autoprefixer: 53 ms
nib: 282 ms (5.4 times slower)
Stylecow: 291 ms (5.5 times slower)
Compass: 3315 ms (63.1 times slower)
To get results on your environment:
npm install
bundle install
npm test prefixers