Vercel Deployment Error: Command "npm run build" exited with 1

Question

I am developing a React app in VS Code. I used create-react-app for setup. I can run the project without any problem with npm start. When I tried to publish the project with Vercel I got errors:

Already tried deleting node_modules and npm install again.

Error! Command "npm run build" exited with 1
Error! Check your logs at https://...

You can see the logs below:

13:55:05.231    Retrieving list of deployment files...
13:55:06.975    Downloading 32 deployment files...
13:55:09.142    Analyzing source code...
13:55:11.289    Installing build runtime...
13:55:15.911    Build runtime installed: 4622.485ms
13:55:20.151    Looking up build cache...
13:55:21.237    Build cache not found
13:55:22.615    Detected package.json
13:55:22.616    Installing dependencies...
13:55:58.492    > [email protected] postinstall /vercel/path0/node_modules/babel-runtime/node_modules/core-js
13:55:58.492    > node -e "try{require('./postinstall')}catch(e){}"
13:55:58.604    > [email protected] postinstall /vercel/path0/node_modules/core-js
13:55:58.604    > node -e "try{require('./postinstall')}catch(e){}"
13:55:58.683    > [email protected] postinstall /vercel/path0/node_modules/core-js-pure
13:55:58.683    > node -e "try{require('./postinstall')}catch(e){}"
13:55:58.801    > [email protected] postinstall /vercel/path0/node_modules/ejs
13:55:58.802    > node ./postinstall.js
13:56:01.182    npm WARN optional SKIPPING OPTIONAL DEPENDENCY: [email protected] (node_modules/webpack-dev-server/node_modules/fsevents):
13:56:01.182    npm WARN notsup SKIPPING OPTIONAL DEPENDENCY: Unsupported platform for [email protected]: wanted {"os":"darwin","arch":"any"} (current: {"os":"linux","arch":"x64"})
13:56:01.191    npm WARN optional SKIPPING OPTIONAL DEPENDENCY: [email protected] (node_modules/watchpack-chokidar2/node_modules/fsevents):
13:56:01.191    npm WARN notsup SKIPPING OPTIONAL DEPENDENCY: Unsupported platform for [email protected]: wanted {"os":"darwin","arch":"any"} (current: {"os":"linux","arch":"x64"})
13:56:01.202    npm WARN optional SKIPPING OPTIONAL DEPENDENCY: [email protected] (node_modules/fsevents):
13:56:01.202    npm WARN notsup SKIPPING OPTIONAL DEPENDENCY: Unsupported platform for [email protected]: wanted {"os":"darwin","arch":"any"} (current: {"os":"linux","arch":"x64"})
13:56:01.210    added 1985 packages from 812 contributors in 37.99s
13:56:02.556    137 packages are looking for funding
13:56:02.556      run `npm fund` for details
13:56:02.831    Running "npm run build"
13:56:03.100    > [email protected] build /vercel/path0
13:56:03.100    > react-scripts build
13:56:04.846    Creating an optimized production build...
13:56:23.548    Treating warnings as errors because process.env.CI = true.
13:56:23.548    Most CI servers set it automatically.
13:56:23.548    Failed to compile.
13:56:23.549    src/components/Counter.js
13:56:23.549      Line 21:6:  React Hook useEffect has a missing dependency: 'props.timeEnds'. Either include it or remove the dependency array  react-hooks/exhaustive-deps
13:56:23.577    npm ERR! code ELIFECYCLE
13:56:23.578    npm ERR! errno 1
13:56:23.581    npm ERR! [email protected] build: `react-scripts build`
13:56:23.581    npm ERR! Exit status 1
13:56:23.583    npm ERR! 
13:56:23.583    npm ERR! Failed at the [email protected] build script.
13:56:23.583    npm ERR! This is probably not a problem with npm. There is likely additional logging output above.
13:56:23.592    npm ERR! A complete log of this run can be found in:
13:56:23.592    npm ERR!     /vercel/.npm/_logs/2021-03-28T10_56_23_582Z-debug.log
13:56:23.606    Error: Command "npm run build" exited with 1

Answer 1

Check whether your codes don't have any warnings. If they have warnings try to fix them and deploy again or ignore them by setting the CI environment variable to false. It would look like this:

CI = false

Answer 2

If you are getting this error:

1. Go to project setting in vercel.com.
2. Go to General.
3. In the "Build & Development Settings", override the Build command and write CI='' npm run build. This solved the error for me.