$ show google/transit
This is the official specification repository for the General Transit Feed Specification (GTFS) and GTFS Realtime, hosted by Google and maintained by the community. It contains extensive documentation defining the structure, fields, and semantics of static transit schedule data (CSV-based) and real-time updates (Protocol Buffers schema). The repository includes governance documents, best practices, example feeds (e.g., sample-feed-1.zip), and asciipb examples. There is no application code, data pipelines, or notebooks; it is purely a specification standard. It serves as the authoritative reference for transit agencies (producers) and application developers (consumers) building interoperable transit tools.
The LLM identified 4 files worth highlighting for reuse:
The canonical Protocol Buffers schema for GTFS Realtime, defining all message types (TripUpdate, VehiclePosition, Alert, TripModifications, etc.), fields, cardinalities, and extension namespaces. This file is reusable as a language-agnostic data contract for any real-time transit feed implementation, and it enables code generation in multiple languages.
The authoritative reference for the GTFS Static schedule specification, covering all tables (agency, stops, routes, trips, stop_times, calendar, fares, shapes, etc.), field definitions, required/optional semantics, and validation rules. This is the single source of truth for implementing a GTFS feed producer or consumer and is reusable across any transit data integration project.
A human-readable ASCII Protocol Buffers example of a GTFS Realtime service alert, demonstrating proper field usage and structure. This file is reusable as a test fixture or reference for generating valid alerts in any realtime feed implementation.
A complete, self-contained sample GTFS static feed including all required files (agency.txt, stops.txt, routes.txt, trips.txt, stop_times.txt, calendar.txt) and optional files (frequencies.txt, etc.). It is reusable as a starting point for development, unit testing, or demonstration of GTFS parsing and visualization tools.