How to fix "Error: Could not find the implementation for builder @angular-devkit/build-angular:dev-server"

I upgrade my angular project to angular 8 and now when I type

ng serve

I receive this error:

Error: Could not find the implementation for builder @angular-devkit/build-angular:dev-server

For the upgrade I used ng update. When I type

ng update

I get:

Using package manager: 'npm'

Collecting installed dependencies...

Found 41 dependencies.

We analyzed your package.json and everything seems to be in order. Good work!

Solution

Maybe this'll help

npm install --save-dev @angular-devkit/build-angular