The term 'next' is not recognized as the name of a cmdlet

$ next build
next : The term 'next' is not recognized as the name of a cmdlet, function, script file, or operable program. Check the spelling of the name, or if a path was included, verify that the path is correct and try again.
At line:1 char:1
+ next build
+ ~~~~
+ CategoryInfo : ObjectNotFound: (next:String) [], CommandNotFoundException
+ FullyQualifiedErrorId : CommandNotFoundException

Solution

1. Make sure your package.json has a "next build" entry such as :

 "scripts": {
    "dev": "next dev",
    "build": "next build",
    "start": "next start"
 },

2. Instead of typing "next build", type "yarn build" or "npm build".