Departures

Upcoming TfL departure times for nearby stations in London. Includes a backend API, a web app, and native Apple apps (iOS, watchOS, widget).

Structure

server/    Cloudflare Worker backend (TypeScript)
web/       Web app (React + TypeScript + Leaflet)
apple/     iOS, watchOS, and widget apps (SwiftUI)

Server

A Cloudflare Worker that queries the TfL API for nearby stops and their upcoming departures. Written in TypeScript, deployed to Cloudflare's edge network.

Setup

Requires Node.js 18+.

cd server
npm install

Create a server/.env file with TfL API credentials for local development:

TFL_APP_ID=your_app_id
TFL_APP_KEY=your_app_key

For production, set them as Cloudflare Worker secrets:

wrangler secret put TFL_APP_ID
wrangler secret put TFL_APP_KEY

Development and deployment

npm run dev        # local preview at http://localhost:8787
npm run check      # type-check
npm run deploy     # deploy to Cloudflare

API

GET /nearest?lat=<lat>&lng=<lng>&stopTypes=<types>&modes=<modes>&radius=<meters>

Parameter	Required	Default	Description
lat	yes		Latitude
lng	yes		Longitude
stopTypes	no	NaptanMetroStation,NaptanRailStation	Comma-separated TfL stop types
modes	no	tube,dlr,overground,elizabeth-line,bus	Comma-separated transport modes
radius	no	2000	Search radius in meters

Response:

{
  "lat": 51.501,
  "lng": -0.124,
  "stations": [
    {
      "station": {
        "id": "940GZZLUGPK",
        "name": "Green Park Underground Station",
        "modes": ["tube"],
        "stopType": "NaptanMetroStation",
        "distance": 210.5,
        "lat": 51.502,
        "lon": -0.143
      },
      "departures": [
        {
          "id": "UniqueTripId",
          "line": "jubilee",
          "mode": "tube",
          "destination": "Stanmore",
          "arrivalTime": "2024-11-27T09:12:30Z"
        }
      ]
    }
  ]
}

Web

A React + TypeScript web app using Leaflet for an interactive map. Supports location via browser geolocation, UK postcode lookup, or manual coordinates.

Setup

cd web
yarn install

Development and deployment

yarn dev           # start Vite dev server
yarn build         # type-check and build
yarn deploy        # deploy to GitHub Pages

The web app imports shared TypeScript types from server/src/types.ts via a symlink at web/src/shared-types.ts.

Apple

Native SwiftUI apps for iOS and watchOS, plus an iOS home/lock screen widget. Features:

• Automatic location-based departure updates
• Configurable station type and transport mode filters
• Map view with station markers (iOS)
• Shared data cache between app and widget via App Group
• Independent watchOS app (works without iPhone)

Setup

Open apple/Departures.xcodeproj in Xcode. Targets:

Target	Platform	Description
Departures	iOS 17+	Main app with map and departure list
DeparturesWatch Watch App	watchOS 10+	Standalone watch app
DeparturesWidgetExtension	iOS 15+	Home/lock screen widget