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    > core-js@2.6.12 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    > core-js@3.9.1 postinstall /vercel/path0/node_modules/core-js
13:55:58.604    > node -e "try{require('./postinstall')}catch(e){}"
13:55:58.683    > core-js-pure@3.9.1 postinstall /vercel/path0/node_modules/core-js-pure
13:55:58.683    > node -e "try{require('./postinstall')}catch(e){}"
13:55:58.801    > ejs@2.7.4 postinstall /vercel/path0/node_modules/ejs
13:55:58.802    > node ./postinstall.js
13:56:01.182    npm WARN optional SKIPPING OPTIONAL DEPENDENCY: fsevents@1.2.13 (node_modules/webpack-dev-server/node_modules/fsevents):
13:56:01.182    npm WARN notsup SKIPPING OPTIONAL DEPENDENCY: Unsupported platform for fsevents@1.2.13: wanted {"os":"darwin","arch":"any"} (current: {"os":"linux","arch":"x64"})
13:56:01.191    npm WARN optional SKIPPING OPTIONAL DEPENDENCY: fsevents@1.2.13 (node_modules/watchpack-chokidar2/node_modules/fsevents):
13:56:01.191    npm WARN notsup SKIPPING OPTIONAL DEPENDENCY: Unsupported platform for fsevents@1.2.13: wanted {"os":"darwin","arch":"any"} (current: {"os":"linux","arch":"x64"})
13:56:01.202    npm WARN optional SKIPPING OPTIONAL DEPENDENCY: fsevents@2.3.2 (node_modules/fsevents):
13:56:01.202    npm WARN notsup SKIPPING OPTIONAL DEPENDENCY: Unsupported platform for fsevents@2.3.2: 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    > last-letter-game@0.1.0 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! last-letter-game@0.1.0 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 last-letter-game@0.1.0 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 environment variable CI to false . It would look like this:

CI = false

Answer 2

If you are getting this error:

1. Go to your 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.

Answer 3

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.

Answer 4

Set CI Environment Variable to false Using Vercel CLI

Go to your project directory and then open the terminal and type

$ vercel env add CI

Vercel CLI 24.0.0
? What’s the value of CLI? false
? Add CLI to which Environments (select multiple, press a)? Production, Preview, Development
✅  Added Environment Variable CLI to Project <Project-name> [776ms]

Now, go to your Vercel app => Settings => Environment Variable Their your will see CLI key has a value set to false

Answer 5

You simply you check your package.json in your project folder, check the build script in the json object.

'script':
{
   "dev": "next dev",
             ==>  "build": "next build", 
    "start": "next start",
    "lint": "next lint"
}

Answer 6

I'm godly

For Deployment follow this procedure if you are getting errors...

1. Run yarn dev in your project folder.
2. Then run terminal as administrator and cd to your project folder then run vercel build command.
3. After it finished successfully, delete the folder inside.vercel\output\functions_next\data
4. Then run vercel deploy prebuilt -> successful (It worked for me)

Answer 7

Go to project setting in vercel.com. Go to General. In the "Build & Development Settings", override the Build command and write

npm run build

This solved the error for me.