Slim Dependencies

[wtgtybhertgeghgtwtg]

Based on a previous discussion.
This is a short list of some of what can be done to reduce some of the larger items that increase the overall size of react-scripts. Excluded are smaller, opinionated, or rejected fixes.

• Currently, three versions of acorn are used. 4.0.3 (560 KB), used by espree, 3.3.0 (520 KB), used by acorn-jsx and webpack, and 2.7.0 4.0.8 (560 KB), used by acorn-globals and jsdom.
  • If Consider using Webpack 2 #183 happens, the version of webpack required will require the same version of acorn that espree uses.
  • An issue has been raised for acorn-jsx to bump their required version of acorn, but there has been no response.
  • The latest release of acorn-globals requires the same version of acorn that webpack and acorn-jsx require, but jsdom uses an older version.
  • An issue has been raised for espree to bump their required version of acorn.
• The version of recursive-readdir required specifically requires "minimatch": "3.0.2", preventing it from deduping with the "minimatch": ">= 3.0.3" in eslint-plugin-import. Which normally wouldn't be that much of a problem, but yarn seems to put minimatch@3.0.2 in the base node_modules folder while placing minimatch@3.0.3 in the node_modules folders of babel-core, eslint-plugin-import, glob, fstream-ignore, multimatch, readdirp, and sane, meaning the same version of a ~30 KB dependency is copied six times over. Fixed with Bump recursive-readdir. #1560.
• browserify-zlib packages ~110 KB of tests. A PR has been filed.
• escope depends on es6-map and es6-weak-map. These two packages, along with their dependants d, es5-ext, es6-iterator, es6-set, and es6-symbol, and event-emitter take up ~560 KB. An issue has been filed on this, but escope does not seem to be actively maintained. It seems eslint will fork has forked escope for the next version, which does not contain the polyfills.
• istanbul-reports packages a .nyc_output folder of ~310 KB. A PR has been filed.
• jsx-ast-utils packages a yarn.lock of ~110 KB. An issue has been filed.
• The version of node-notifier currently used by jest required includes a CLI that is not used and depends on a framework that is not used elsewhere in react-scripts. Updates node-notifier dep of jest-cli to v5 jestjs/jest#2718, which is included in jest@19.0.0, resolved this.

[gaearon]

Amazing investigation, thank you.

[wtgtybhertgeghgtwtg]

Another thing that might help would be trying greenkeeper to keep things up to date. There's an issue with babel I am noticing.

1. react-scripts requires babel-core@6.17.0.
2. babel-core requires babel-register >= 6.16.0. Since the latest is babel-register@6.18.0, it grabs that.
3. babel-register@6.18.0 requires babel-core >= 6.18.0, but we only have babel-core@6.17.0 locally, so it has to grab another copy, babel-core@6.18.2.

Assuming this isn't just a program with my machine, I think you can run yarn list babel-core to see this. If not, please correct me.

[wtgtybhertgeghgtwtg]

And I don't know why I'm just now noticing this, but since the version of fbjs that react upon depends on a different major version of core-js than Babel and Friends, that is not deduping properly, either. Once react bumps to at least fbjs@0.9.0-alpha.1, it should save something like 1 to 14 megabytes, depending on how yarn dedupes it. Although I'd imagine that fbjs@0.9.0 would have to come out of alpha first.

[gaearon]

Also interesting: apparently installed size is larger with Yarn? https://twitter.com/petrhurtak/status/812356423795568640

[wtgtybhertgeghgtwtg]

I think that's because of how yarn and npm dedupe things. The most obvious example would be with core-js; fbjs requires one version, babel-runtime requires another. Installing npm only leaves two copies of core-js, but yarn seems to install a copy in every directory that requires babel-runtime.

You can see this by going to the babel-generator folder under node_modules; when installed by npm, it should not have a node_modules folder, when installed by yarn, it should have one with .bin, babel-runtime, and core-js.

[tbillington]

Can confirm that yarn size is between 20-50% larger and the same % increase in total number of files due to the structure under yarn.

[mmrath]

Instead of react-scripts I used react-scripts-ts, node_modules folder was 137MB instead of 561MB

[Daniel15]

but yarn seems to put minimatch@3.0.2 in the base node_modules folder while placing minimatch@3.0.3 in the node_modules folders of babel-core, eslint-plugin-import, glob, fstream-ignore, multimatch, readdirp, and sane, meaning the same version of a ~30 KB dependency is copied six times over.

yarnpkg/yarn#2306 should help with that, once implemented!

[JaKXz]

The istanbul-reports PR has been merged and released! 😃

[gaearon]

Instead of react-scripts I used react-scripts-ts, node_modules folder was 137MB instead of 561MB

This is likely because you have Yarn installed, and Yarn has a bug.
This will be fixed in next release: #1397

[wtgtybhertgeghgtwtg]

acorn-globals now uses acorn@4.0.8, as does jsdom. However, I noticed that espree depends on a specific version of acorn (acorn@4.0.4), so there are still three versions required.

[benjaminapetersen]

Somewhat related, I was a bit alarmed at my first run of create-react-app yesterday, when I checked the size of my node_modules folder and found 179,491,959 bytes (556.6 MB on disk) for 110,557 items. 556MB is quite a lot!

I was looking for a light-weight way to get up and running with react, ideally to spin up a handful of hello-world apps locally for running through tutorials, etc. Over half a gig does discourage creating a number of quick little prototypes.

I'm new to the react world though, so perhaps there is a good resource for doing this!

[gaearon]

@benjaminapetersen

This is a different issue and caused by Yarn bug: #1397. We'll work around it in 0.9.0.

[benjaminapetersen]

Indeed it is! Nuked the node_modules directory & reinstalled w/nmp instead of yarn, dropped to 72,495,611 bytes (131.7 MB on disk) for 1,922 items

131MB is a lot easier to swallow than 556MB.

[gaearon]

This is why you should be careful adopting new tech 😉

[wtgtybhertgeghgtwtg]

jest@19.0.0 has been released, which contains the node-notifier bump. It's also about a megabyte smaller.

[mhart]

You can take a high-level view here: http://pkgsize.com/react-scripts.html

jest, webpack, autoprefixer and eslint are the four largest contributors.

autoprefixer largely due to the ever increasing caniuse-db: http://pkgsize.com/autoprefixer.html (is autoprefixer really a must-have?)

jest mostly due to jest-cli mostly due to jsdom stuff and istanbul-api: http://pkgsize.com/jest-cli.html

... and they all include a whole bunch of babel libs – of which core-js makes up a large part: http://pkgsize.com/babel-runtime.html

[gaearon]

I wonder how this compares to master since we switched to webpack 2 and might have new regressions (or it might be better). We should cut a canary release.

[JaKXz]

FWIW a PR has been filed for browserify-zlib: browserify/browserify-zlib#22

[wtgtybhertgeghgtwtg]

jest, webpack, autoprefixer and eslint are the four largest contributors.

jest has an issue similar to this one. You might be able to get webpack and eslint interested if you asked.

autoprefixer largely due to the ever increasing caniuse-db: http://pkgsize.com/autoprefixer.html (is autoprefixer really a must-have?)

It's gonna be there anyway, since cssnano depends on it.

[gaearon]

I'll close this as stale. (But efforts to further dedupe are welcome!)