Damu converts NeTEX datasets into GTFS datasets. The actual GTFS conversion is performed by the Netex-to-GTFS converter library.
When Chouette or Uttu complete a NeTEx export, Marduk notifies Damu. Damu downloads the exported NeTEx dataset from a bucket in Google Cloud Storage, converts it to GTFS, uploads it back to the GCS bucket and notifies Marduk.