anchor.diff:  
       PersistentStore store = null;
       if (argValues["flavor"] == "postgres") {
  -      if (new File.fromUri(dbConfigURI).existsSync()) {
  -        var dbConfig = new MigrationConfiguration(dbConfigURI.path).migration;
  +      var dbConfigFile = new File.fromUri(dbConfigURI);
  +      if (dbConfigFile.existsSync()) {
  +        var dbConfig = new DatabaseConnectionConfiguration();
  +        try {
  +          dbConfig.readFromMap(loadYaml(dbConfigFile.readAsStringSync()) as Map<String, dynamic>);
  +        } catch (e) {
  +          print("Invalid dbconfig. Expected $_dbConfigFormat\nat ${dbConfigURI}.");
  +          rethrow;
  +        }
           store = new PostgreSQLPersistentStore.fromConnectionInfo(dbConfig.username, dbConfig.password, dbConfig.host, dbConfig.port, dbConfig.databaseName);
         }
       } else {
  
positive.code: 
  
    Future cleanup() async {
      await executor.persistentStore.close();
    }
  
  
    String _getPackageName(Uri projectURI) {
      var yamlContents = new File.fromUri(projectURI.resolve("pubspec.yaml")).readAsStringSync();
  
negative.code: part of aqueduct;
  
  class MigrationRunner extends CLICommand {
    MigrationExecutor executor;
  