architecture.md

Architecture

Major Services

None. All processing is local batch scripts. No web services, APIs, or daemons.

Datastore Choices

• Input: .pbf (OSM extract), .csv (NBI bridge data), .gpkg (NHD streams)
• Intermediate/output: .gpkg and .csv files written to output-data/<state>/
• All paths configured in hydrography-approach/config.yml

Queues / Jobs

None. Pipeline stages run sequentially in a single Python process.

Third-Party Dependencies

Python: see requirements.txt. External tools: QGIS-LTR, Osmium, GDAL, JOSM with Scripting Plugin.

Auth Model

None. All data sources (Geofabrik, FHWA, USGS) are public. OSM upload requires a personal OSM account and is done manually via JOSM.

Tenancy

Not applicable.