STACD: STAC Extension with DAGs for Geospatial Data and Algorithm Management

Geospatial datasets have complex lineages that are crucial for reproducibility and understanding data provenance, yet current metadata standards like STAC (SpatioTemporal Asset Catalog) provide limited support for capturing complete processing workflows. We propose STACD (STAC extension with DAGs), an extension to STAC specifications that incorporates Directed Acyclic Graph (DAG) representations along with defining algorithms and version changes in the workflows. We also provide a reference implementation on Apache Airflow to demonstrate STACD capabilities such as selective recomputation when some datasets or algorithms in a DAG are updated, complete lineage construction for a dataset, and opportunities for improved collaboration and distributed processing that arise with this standard.