Switch from sass to sass-embedded

[aduth]

Previously: #5862 (comment)

Why: Improve performance of Sass compilation, using an official native Dart binary instead of the compiled-to-JavaScript sass implementation.

We had previously been blocked by sass/embedded-host-node#117, which was causing issues with downloading the binary in our build environments. This has since been resolved as of v1.53.0 (see changelog).

Performance Impact:

Average of 5 runs of yarn build:css:

Before: 9.9s
After: 4.4s

[mitchellhenke]

One question I had was whether this means the sass-embedded binary gets downloaded dynamically or if it gets installed as part of yarn install (and gets cached)?

[aduth]

One question I had was whether this means the sass-embedded binary gets downloaded dynamically or if it gets installed as part of yarn install (and gets cached)?

It's downloaded as a postinstall script of the package:

https://github.com/sass/embedded-host-node/blob/main/package.json#L25

I believe it would be downloaded into node_modules (node_modules/sass-embedded/lib/src/vendor/...), so it would be cached if we're caching node_modules ?

[mitchellhenke]

One question I had was whether this means the sass-embedded binary gets downloaded dynamically or if it gets installed as part of yarn install (and gets cached)?

It's downloaded as a postinstall script of the package:

https://github.com/sass/embedded-host-node/blob/main/package.json#L25

I believe it would be downloaded into node_modules (node_modules/sass-embedded/lib/src/vendor/...), so it would be cached if we're caching node_modules ?

Yep, that's perfect!