Angular CLI not working

I’m trying to setup an Angular site. When attempting to run ng serve I get this error:

An unhandled exception occurred: Cannot find module ‘@angular-devkit/build-angular/package.json’
Require stack:

  • /app/node_modules/@angular-devkit/architect/node/node-modules-architect-host.js
  • /app/node_modules/@angular-devkit/architect/node/index.js
  • /app/node_modules/@angular/cli/models/architect-command.js
  • /app/node_modules/@angular/cli/commands/serve-impl.js
  • /app/node_modules/@angular-devkit/schematics/tools/export-ref.js
  • /app/node_modules/@angular-devkit/schematics/tools/index.js
  • /app/node_modules/@angular/cli/utilities/json-schema.js
  • /app/node_modules/@angular/cli/models/command-runner.js
  • /app/node_modules/@angular/cli/lib/cli/index.js
  • /app/node_modules/@angular/cli/lib/init.js
  • /app/node_modules/@angular/cli/bin/ng
    See “/tmp/ng-t50mVp/angular-errors.log” for further details.

Additionally running ng new foo cause the ide to crash after some time while installing packages. Any ideas?