Create-react-app: CRA 2: Significantly slower compilation

[dmitriy-kudelko]

Is this a bug report?

Sort of

Did you try recovering your dependencies?

Yes

Environment

System: OS: macOS 10.14 CPU: x64 Intel(R) Core(TM) i7-4770HQ CPU @ 2.20GHz Binaries: Node: 8.11.2 - /usr/local/bin/node Yarn: 1.9.4 - /usr/local/bin/yarn npm: 5.6.0 - /usr/local/bin/npm Browsers: Chrome: 69.0.3497.100 Safari: 12.0 npmPackages: react: ^16.4.1 => 16.4.2 react-dom: ^16.4.1 => 16.4.2 react-scripts: 2.0.4 => 2.0.4 npmGlobalPackages: create-react-app: Not Found

We tried migrating from 2.0.0-next.3e165448 to a stable release (2.0.4) but noticed a significant increase of the compilation time:

Version: Dev/Prod:
2.0.0-next.3e165448: 0:49/3:03
2.0.4: 1:39/4:20

is it something expected because of adding some new features, or any ideas why it started to happen?

Thanks.

[Timer]

We had to remove thread-loader because it had too many caveats. This resulted in slower builds for large bundles, but should be offset by caching/warm build.
webpack 5 should fix this via built-in caching skipping loaders all together.