docs: function postProcess( errorCode ) {
  	if ( errorCode ) {
  		console.error( `running npm for installing missing dependencies ${collected.join( ", " )} exited on error (${errorCode})` );
  	} else if ( exec ) {
  		const cmd = exec.join( " " );
  
  		if ( !quiet ) {
  			console.error( `invoking follow-up command: ${cmd}` );
  		}
  
  		const followup = Child.exec( cmd );
  
  		followup.stdout.pipe( process.stdout );
  		followup.stderr.pipe( process.stderr );
  
  		followup.on( "exit", code => {
  			process.exit( code );
  		} );
  
  		return;
  	}
  
  	process.exit( errorCode );
  }