Moving our CI from npm to yarn, fresh install performance http://blog.fgribreau.com/2017/01/how-we-reduced-by-37-our-nodejs-project.html

build.sh

time docker run --rm -v $(pwd):/src mkenney/npm npm install

12:04:14 real	3m33.500s
12:04:14 user	0m0.780s
12:04:14 sys	0m0.716s

time docker run --rm -v $(pwd):/workspace kkarczmarczyk/node-yarn yarn install

12:07:29 real	2m0.769s
12:07:29 user	0m0.164s
12:07:29 sys	0m0.032s