constructor(project, networkId) {
    super();

    this.project = project;
    this.networkId = networkId;

    this.configWatcher = null;
    this.contractBuildDirectoryWatcher = null;
    this.dirWatchers = {};

    this.contracts = [];
    this.fileToContractIdx = {};

    this.start();
  }
Detects when there are new/changed/removed contract artifacts in contracts_build_directory