ERROR in ngcc is already running at process with id 21893. If you are running multiple builds in parallel then you should pre-process your node_modules via the command line ngcc tool before starting the builds; code example

Example: ERROR in ngcc is already running at process with id 8108. If you are running multiple builds in parallel then you should pre-process your node_modules via the command line ngcc tool before starting the builds;

//This happens when ngcc (Angular compatibility compiler) is not finished doing what it does, you must have enabled ivy in your Angular project. read here for more info about ivy.

1. First try to run npm install again, to see if it fixes your problem.
2. Try to run ngcc manually.
3. remove this file node_modules/@angular/compiler-cli/ngcc/__ngcc_lock_file__
4. If none of the above worked, then remove node_modules directory and try npm i again