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react-scripts@2.0 takes forever to build

See original GitHub issue

Recently, I upgraded a CRA project to the latest react-scripts v2 release (2.0.0-next.2150693d), and quickly realized that “yarn build” takes hours to build my project. Seems like it hangs at “Creating an optimized production build” for some reasons. That was quite unexpected since the previous version of react-scripts that I used (v1.1.5) could build the project just fine, though production build took a fairly long time (~15min).

FYI, before I was able to build, I had to manually update eslint to version 5.6.0, because react-scripts v2 requires it and a different version of eslint (3.9.1) detected higher up in the tree isn’t compatible with react-scripts@2.0, sorta similar to this known issue. I guess this approach could prevent users from breaking react-scripts initial dev dependency? (link).

Environment

node -v: v8.12.0
npm -v: v6.4.1
yarn -v: (if you use Yarn): v1.9.4
react-scripts: (if you haven’t ejected): 2.0.0-next.2150693d
Ubuntu 16.04 LTS

Expected Behavior

yarn build succeeds

Actual Behavior

Get stuck at “Creating an optimized production build…” forever.

Reproducible Demo

Here’s my package.json

Issue Analytics

State:
Created 5 years ago
Comments:20 (11 by maintainers)

Top GitHub Comments

1reaction

Timercommented, Sep 23, 2018

I would definitely remove your rewire then with v2, it might be causing some bad configuration. Please try GENERATE_SOURCEMAP=false yarn build with no rewires applied.

Unfortunately, we’re not going to be of much help unless if you can share the project with us privately.

0reactions

Timercommented, Sep 26, 2018

Closing since we were not given a reproducing project

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