🚆 Railways & Public Transport · C4 Architecture · Pro
Multimodal Journey Planner
A journey planner that combines metro, bus, suburban train and last-mile options into one trip plan with a single ticket.
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Drawing diagram…
What this diagram shows
- Timetables from all operators are combined in one format
- Live delays change the suggested route
- One QR ticket works across operators
Prompt used
Journey planner platform: riders use an app that calls a trip planner service. The planner uses a routing engine (OpenTripPlanner) with GTFS timetables from metro, bus and suburban rail operators and live GTFS-realtime delay feeds. A ticketing service sells one QR ticket covering all legs and splits revenue among operators. Last-mile options (bike, auto) come from partner APIs.
Mermaid code
C4Container
title Multimodal Journey Planner
Person(rider, "Rider", "Plans and pays for trips")
System_Boundary(jp, "Journey Planner") {
Container(app, "Rider App", "Flutter", "Plan, pay, show QR")
Container(plan, "Trip Planner API", "Java", "Trip options")
Container(route, "Routing Engine", "OpenTripPlanner", "Graph of all networks")
Container(ingest, "Timetable Ingest", "Python", "GTFS and realtime feeds")
Container(tix, "Ticketing Service", "Node.js", "One QR for all legs")
ContainerDb(db, "Tickets DB", "PostgreSQL", "Tickets and revenue split")
}
System_Ext(ops, "Transit Operators", "Metro, bus, suburban rail")
System_Ext(lm, "Last-mile Partners", "Bikes, autos")
Rel(rider, app, "Uses")
Rel(app, plan, "Plan trip")
Rel(plan, route, "Routes")
Rel(ingest, ops, "Reads GTFS feeds")
Rel(ingest, route, "Updates graph")
Rel(plan, lm, "Last-mile options")
Rel(app, tix, "Buys ticket")
Rel(tix, db, "Reads/writes")
Rel(tix, ops, "Validates and settles")Related templates
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