feat: add GET /api/feed endpoint

Expose the user's current feed via GET /api/feed. Returns
cached feed from engine.lastFeed(), falling back to
engine.refresh() when no cache exists.

Auth middleware is injected as a dependency to allow test
substitution via mockAuthSessionMiddleware.

Co-authored-by: Ona <no-reply@ona.com>

.devcontainer/devcontainer.json

@@ -10,12 +10,13 @@
 		"context": ".",
 		"dockerfile": "Dockerfile"
 	},
-	"postStartCommand": "./scripts/setup-git.sh && ./scripts/setup-nvim.sh"
+	"postCreateCommand": "bun install",
+	"postStartCommand": "./scripts/setup-git.sh && ./scripts/setup-nvim.sh",
 	// Features add additional features to your environment. See https://containers.dev/features
 	// Beware: features are not supported on all platforms and may have unintended side-effects.
-	// "features": {
+	"features": {
-	//   "ghcr.io/devcontainers/features/docker-in-docker": {
+		"ghcr.io/tailscale/codespace/tailscale": {
-	//     "moby": false
+			"version": "latest"
-	//   }
+		}
-	// }
+	}
 }

.gitignore

@@ -32,3 +32,4 @@ report.[0-9]_.[0-9]_.[0-9]_.[0-9]_.json
 
 # Finder (MacOS) folder config
 .DS_Store
+core

.ona/automations.yaml

@@ -0,0 +1,8 @@
+services:
+  expo:
+    name: Expo Dev Server
+    description: Expo development server for aris-client
+    triggeredBy:
+      - postDevcontainerStart
+    commands:
+      start: cd apps/aris-client && ./scripts/run-dev-server.sh

apps/aris-backend/.env.example

@@ -6,3 +6,9 @@ BETTER_AUTH_SECRET=
 
 # Base URL of the backend
 BETTER_AUTH_URL=http://localhost:3000
+
+# Apple WeatherKit credentials
+WEATHERKIT_PRIVATE_KEY=
+WEATHERKIT_KEY_ID=
+WEATHERKIT_TEAM_ID=
+WEATHERKIT_SERVICE_ID=

apps/aris-backend/package.json

@@ -11,7 +11,9 @@
 	"dependencies": {
 		"@aris/core": "workspace:*",
 		"@aris/source-location": "workspace:*",
+		"@aris/source-tfl": "workspace:*",
 		"@aris/source-weatherkit": "workspace:*",
+		"arktype": "^2.1.29",
 		"better-auth": "^1",
 		"hono": "^4",
 		"pg": "^8"

apps/aris-backend/src/auth/session-middleware.ts

@@ -1,13 +1,20 @@
-import type { Context, Next } from "hono"
+import type { Context, MiddlewareHandler, Next } from "hono"
+
+import type { AuthSession, AuthUser } from "./session.ts"
 
 import { auth } from "./index.ts"
 
-type SessionUser = typeof auth.$Infer.Session.user
-type Session = typeof auth.$Infer.Session.session
-
 export interface SessionVariables {
-	user: SessionUser | null
+	user: AuthUser | null
-	session: Session | null
+	session: AuthSession | null
+}
+
+export type AuthSessionEnv = { Variables: SessionVariables }
+
+export type AuthSessionMiddleware = MiddlewareHandler<AuthSessionEnv>
+
+declare module "hono" {
+	interface ContextVariableMap extends SessionVariables {}
 }
 
 /**
@@ -48,7 +55,22 @@ export async function requireSession(c: Context, next: Next): Promise<Response |
  */
 export async function getSessionFromHeaders(
 	headers: Headers,
-): Promise<{ user: SessionUser; session: Session } | null> {
+): Promise<{ user: AuthUser; session: AuthSession } | null> {
 	const session = await auth.api.getSession({ headers })
 	return session
 }
+
+/**
+ * Test-only middleware that injects a fake user and session.
+ * Pass userId to simulate an authenticated request, or omit to get 401.
+ */
+export function mockAuthSessionMiddleware(userId?: string): AuthSessionMiddleware {
+	return async (c: Context, next: Next): Promise<Response | void> => {
+		if (!userId) {
+			return c.json({ error: "Unauthorized" }, 401)
+		}
+		c.set("user", { id: userId } as AuthUser)
+		c.set("session", { id: "mock-session" } as AuthSession)
+		await next()
+	}
+}

apps/aris-backend/src/auth/session.ts

@@ -0,0 +1,4 @@
+import type { auth } from "./index.ts"
+
+export type AuthUser = typeof auth.$Infer.Session.user
+export type AuthSession = typeof auth.$Infer.Session.session

apps/aris-backend/src/feed/http.test.ts

@@ -0,0 +1,140 @@
+import type { ActionDefinition, Context, FeedItem, FeedSource } from "@aris/core"
+
+import { describe, expect, test } from "bun:test"
+import { Hono } from "hono"
+
+import { mockAuthSessionMiddleware } from "../auth/session-middleware.ts"
+import { UserSessionManager } from "../session/index.ts"
+import { registerFeedHttpHandlers } from "./http.ts"
+
+interface FeedResponse {
+	items: Array<{
+		id: string
+		type: string
+		priority: number
+		timestamp: string
+		data: Record<string, unknown>
+	}>
+	errors: Array<{ sourceId: string; error: string }>
+}
+
+function createStubSource(id: string, items: FeedItem[] = []): FeedSource {
+	return {
+		id,
+		async listActions(): Promise<Record<string, ActionDefinition>> {
+			return {}
+		},
+		async executeAction(): Promise<unknown> {
+			return undefined
+		},
+		async fetchContext(): Promise<Partial<Context> | null> {
+			return null
+		},
+		async fetchItems() {
+			return items
+		},
+	}
+}
+
+function buildTestApp(sessionManager: UserSessionManager, userId?: string) {
+	const app = new Hono()
+	registerFeedHttpHandlers(app, {
+		sessionManager,
+		authSessionMiddleware: mockAuthSessionMiddleware(userId),
+	})
+	return app
+}
+
+describe("GET /api/feed", () => {
+	test("returns 401 without auth", async () => {
+		const manager = new UserSessionManager([])
+		const app = buildTestApp(manager)
+
+		const res = await app.request("/api/feed")
+
+		expect(res.status).toBe(401)
+	})
+
+	test("returns cached feed when available", async () => {
+		const items: FeedItem[] = [
+			{
+				id: "item-1",
+				type: "test",
+				priority: 0.8,
+				timestamp: new Date("2025-01-01T00:00:00.000Z"),
+				data: { value: 42 },
+			},
+		]
+		const manager = new UserSessionManager([() => createStubSource("test", items)])
+		const app = buildTestApp(manager, "user-1")
+
+		// Prime the cache
+		const session = manager.getOrCreate("user-1")
+		await session.engine.refresh()
+		expect(session.engine.lastFeed()).not.toBeNull()
+
+		const res = await app.request("/api/feed")
+
+		expect(res.status).toBe(200)
+		const body = (await res.json()) as FeedResponse
+		expect(body.items).toHaveLength(1)
+		expect(body.items[0]!.id).toBe("item-1")
+		expect(body.items[0]!.type).toBe("test")
+		expect(body.items[0]!.priority).toBe(0.8)
+		expect(body.items[0]!.timestamp).toBe("2025-01-01T00:00:00.000Z")
+		expect(body.errors).toHaveLength(0)
+	})
+
+	test("forces refresh when no cached feed", async () => {
+		const items: FeedItem[] = [
+			{
+				id: "fresh-1",
+				type: "test",
+				priority: 0.5,
+				timestamp: new Date("2025-06-01T12:00:00.000Z"),
+				data: { fresh: true },
+			},
+		]
+		const manager = new UserSessionManager([() => createStubSource("test", items)])
+		const app = buildTestApp(manager, "user-1")
+
+		// No prior refresh — lastFeed() returns null, handler should call refresh()
+		const res = await app.request("/api/feed")
+
+		expect(res.status).toBe(200)
+		const body = (await res.json()) as FeedResponse
+		expect(body.items).toHaveLength(1)
+		expect(body.items[0]!.id).toBe("fresh-1")
+		expect(body.items[0]!.data.fresh).toBe(true)
+		expect(body.errors).toHaveLength(0)
+	})
+
+	test("serializes source errors as message strings", async () => {
+		const failingSource: FeedSource = {
+			id: "failing",
+			async listActions() {
+				return {}
+			},
+			async executeAction() {
+				return undefined
+			},
+			async fetchContext() {
+				return null
+			},
+			async fetchItems() {
+				throw new Error("connection timeout")
+			},
+		}
+		const manager = new UserSessionManager([() => failingSource])
+		const app = buildTestApp(manager, "user-1")
+
+		const res = await app.request("/api/feed")
+
+		expect(res.status).toBe(200)
+		const body = (await res.json()) as FeedResponse
+		expect(body.items).toHaveLength(0)
+		expect(body.errors).toHaveLength(1)
+		expect(body.errors[0]!.sourceId).toBe("failing")
+		expect(body.errors[0]!.error).toBe("connection timeout")
+	})
+})

apps/aris-backend/src/feed/http.ts

@@ -0,0 +1,41 @@
+import type { Context, Hono } from "hono"
+
+import { createMiddleware } from "hono/factory"
+
+import type { AuthSessionMiddleware } from "../auth/session-middleware.ts"
+import type { UserSessionManager } from "../session/index.ts"
+
+type Env = { Variables: { sessionManager: UserSessionManager } }
+
+interface FeedHttpHandlersDeps {
+	sessionManager: UserSessionManager
+	authSessionMiddleware: AuthSessionMiddleware
+}
+
+export function registerFeedHttpHandlers(
+	app: Hono,
+	{ sessionManager, authSessionMiddleware }: FeedHttpHandlersDeps,
+) {
+	const inject = createMiddleware<Env>(async (c, next) => {
+		c.set("sessionManager", sessionManager)
+		await next()
+	})
+
+	app.get("/api/feed", inject, authSessionMiddleware, handleGetFeed)
+}
+
+async function handleGetFeed(c: Context<Env>) {
+	const user = c.get("user")!
+	const sessionManager = c.get("sessionManager")
+	const session = sessionManager.getOrCreate(user.id)
+
+	const feed = session.engine.lastFeed() ?? (await session.engine.refresh())
+
+	return c.json({
+		items: feed.items,
+		errors: feed.errors.map((e) => ({
+			sourceId: e.sourceId,
+			error: e.error.message,
+		})),
+	})
+}

apps/aris-backend/src/location/http.ts

@@ -0,0 +1,56 @@
+import type { Context, Hono } from "hono"
+
+import { type } from "arktype"
+import { createMiddleware } from "hono/factory"
+
+import type { UserSessionManager } from "../session/index.ts"
+
+import { requireSession } from "../auth/session-middleware.ts"
+
+type Env = { Variables: { sessionManager: UserSessionManager } }
+
+const locationInput = type({
+	lat: "number",
+	lng: "number",
+	accuracy: "number",
+	timestamp: "string.date.iso",
+})
+
+export function registerLocationHttpHandlers(
+	app: Hono,
+	{ sessionManager }: { sessionManager: UserSessionManager },
+) {
+	const inject = createMiddleware<Env>(async (c, next) => {
+		c.set("sessionManager", sessionManager)
+		await next()
+	})
+
+	app.post("/api/location", inject, requireSession, handleUpdateLocation)
+}
+
+async function handleUpdateLocation(c: Context<Env>) {
+	let body: unknown
+	try {
+		body = await c.req.json()
+	} catch {
+		return c.json({ error: "Invalid JSON" }, 400)
+	}
+
+	const result = locationInput(body)
+
+	if (result instanceof type.errors) {
+		return c.json({ error: result.summary }, 400)
+	}
+
+	const user = c.get("user")!
+	const sessionManager = c.get("sessionManager")
+	const session = sessionManager.getOrCreate(user.id)
+	await session.engine.executeAction("aris.location", "update-location", {
+		lat: result.lat,
+		lng: result.lng,
+		accuracy: result.accuracy,
+		timestamp: new Date(result.timestamp),
+	})
+
+	return c.body(null, 204)
+}

apps/aris-backend/src/location/service.test.ts

@@ -1,111 +0,0 @@
-import { describe, expect, test } from "bun:test"
-
-import { UserNotFoundError } from "../lib/error.ts"
-import { LocationService } from "./service.ts"
-
-describe("LocationService", () => {
-	test("feedSourceForUser creates source on first call", () => {
-		const service = new LocationService()
-		const source = service.feedSourceForUser("user-1")
-
-		expect(source).toBeDefined()
-		expect(source.id).toBe("location")
-	})
-
-	test("feedSourceForUser returns same source for same user", () => {
-		const service = new LocationService()
-		const source1 = service.feedSourceForUser("user-1")
-		const source2 = service.feedSourceForUser("user-1")
-
-		expect(source1).toBe(source2)
-	})
-
-	test("feedSourceForUser returns different sources for different users", () => {
-		const service = new LocationService()
-		const source1 = service.feedSourceForUser("user-1")
-		const source2 = service.feedSourceForUser("user-2")
-
-		expect(source1).not.toBe(source2)
-	})
-
-	test("updateUserLocation updates the source", () => {
-		const service = new LocationService()
-		const source = service.feedSourceForUser("user-1")
-		const location = {
-			lat: 51.5074,
-			lng: -0.1278,
-			accuracy: 10,
-			timestamp: new Date(),
-		}
-
-		service.updateUserLocation("user-1", location)
-
-		expect(source.lastLocation).toEqual(location)
-	})
-
-	test("updateUserLocation throws if source does not exist", () => {
-		const service = new LocationService()
-		const location = {
-			lat: 51.5074,
-			lng: -0.1278,
-			accuracy: 10,
-			timestamp: new Date(),
-		}
-
-		expect(() => service.updateUserLocation("user-1", location)).toThrow(UserNotFoundError)
-	})
-
-	test("lastUserLocation returns null for unknown user", () => {
-		const service = new LocationService()
-
-		expect(service.lastUserLocation("unknown")).toBeNull()
-	})
-
-	test("lastUserLocation returns last location", () => {
-		const service = new LocationService()
-		service.feedSourceForUser("user-1")
-		const location1 = {
-			lat: 51.5074,
-			lng: -0.1278,
-			accuracy: 10,
-			timestamp: new Date(),
-		}
-		const location2 = {
-			lat: 52.0,
-			lng: -0.2,
-			accuracy: 5,
-			timestamp: new Date(),
-		}
-
-		service.updateUserLocation("user-1", location1)
-		service.updateUserLocation("user-1", location2)
-
-		expect(service.lastUserLocation("user-1")).toEqual(location2)
-	})
-
-	test("removeUser removes the source", () => {
-		const service = new LocationService()
-		service.feedSourceForUser("user-1")
-		const location = {
-			lat: 51.5074,
-			lng: -0.1278,
-			accuracy: 10,
-			timestamp: new Date(),
-		}
-
-		service.updateUserLocation("user-1", location)
-		service.removeUser("user-1")
-
-		expect(service.lastUserLocation("user-1")).toBeNull()
-	})
-
-	test("removeUser allows new source to be created", () => {
-		const service = new LocationService()
-		const source1 = service.feedSourceForUser("user-1")
-
-		service.removeUser("user-1")
-		const source2 = service.feedSourceForUser("user-1")
-
-		expect(source1).not.toBe(source2)
-	})
-})

apps/aris-backend/src/location/service.ts

@@ -1,55 +0,0 @@
-import { LocationSource, type Location } from "@aris/source-location"
-
-import { UserNotFoundError } from "../lib/error.ts"
-
-/**
- * Manages LocationSource instances per user.
- */
-export class LocationService {
-	private sources = new Map<string, LocationSource>()
-
-	/**
-	 * Get or create a LocationSource for a user.
-	 * @param userId - The user's unique identifier
-	 * @returns The user's LocationSource instance
-	 */
-	feedSourceForUser(userId: string): LocationSource {
-		let source = this.sources.get(userId)
-		if (!source) {
-			source = new LocationSource()
-			this.sources.set(userId, source)
-		}
-		return source
-	}
-
-	/**
-	 * Update location for a user.
-	 * @param userId - The user's unique identifier
-	 * @param location - The new location data
-	 * @throws {UserNotFoundError} If no source exists for the user
-	 */
-	updateUserLocation(userId: string, location: Location): void {
-		const source = this.sources.get(userId)
-		if (!source) {
-			throw new UserNotFoundError(userId)
-		}
-		source.pushLocation(location)
-	}
-
-	/**
-	 * Get last known location for a user.
-	 * @param userId - The user's unique identifier
-	 * @returns The last location, or null if none exists
-	 */
-	lastUserLocation(userId: string): Location | null {
-		return this.sources.get(userId)?.lastLocation ?? null
-	}
-
-	/**
-	 * Remove a user's LocationSource.
-	 * @param userId - The user's unique identifier
-	 */
-	removeUser(userId: string): void {
-		this.sources.delete(userId)
-	}
-}

apps/aris-backend/src/server.ts

@@ -1,12 +1,38 @@
+import { LocationSource } from "@aris/source-location"
 import { Hono } from "hono"
 
 import { registerAuthHandlers } from "./auth/http.ts"
+import { requireSession } from "./auth/session-middleware.ts"
+import { registerFeedHttpHandlers } from "./feed/http.ts"
+import { registerLocationHttpHandlers } from "./location/http.ts"
+import { UserSessionManager } from "./session/index.ts"
+import { WeatherSourceProvider } from "./weather/provider.ts"
 
-const app = new Hono()
+function main() {
+	const sessionManager = new UserSessionManager([
+		() => new LocationSource(),
+		new WeatherSourceProvider({
+			credentials: {
+				privateKey: process.env.WEATHERKIT_PRIVATE_KEY!,
+				keyId: process.env.WEATHERKIT_KEY_ID!,
+				teamId: process.env.WEATHERKIT_TEAM_ID!,
+				serviceId: process.env.WEATHERKIT_SERVICE_ID!,
+			},
+		}),
+	])
 
-app.get("/health", (c) => c.json({ status: "ok" }))
+	const app = new Hono()
 
-registerAuthHandlers(app)
+	app.get("/health", (c) => c.json({ status: "ok" }))
+
+	registerAuthHandlers(app)
+	registerFeedHttpHandlers(app, { sessionManager, authSessionMiddleware: requireSession })
+	registerLocationHttpHandlers(app, { sessionManager })
+
+	return app
+}
+
+const app = main()
 
 export default {
 	port: 3000,

apps/aris-backend/src/session/feed-source-provider.ts

@@ -0,0 +1,9 @@
+import type { FeedSource } from "@aris/core"
+
+export interface FeedSourceProvider {
+	feedSourceForUser(userId: string): FeedSource
+}
+
+export type FeedSourceProviderFn = (userId: string) => FeedSource
+
+export type FeedSourceProviderInput = FeedSourceProvider | FeedSourceProviderFn

apps/aris-backend/src/session/index.ts

@@ -0,0 +1,7 @@
+export type {
+	FeedSourceProvider,
+	FeedSourceProviderFn,
+	FeedSourceProviderInput,
+} from "./feed-source-provider.ts"
+export { UserSession } from "./user-session.ts"
+export { UserSessionManager } from "./user-session-manager.ts"

apps/aris-backend/src/session/user-session-manager.test.ts

@@ -0,0 +1,166 @@
+import type { WeatherKitClient, WeatherKitResponse } from "@aris/source-weatherkit"
+
+import { LocationSource } from "@aris/source-location"
+import { describe, expect, mock, test } from "bun:test"
+
+import { WeatherSourceProvider } from "../weather/provider.ts"
+import { UserSessionManager } from "./user-session-manager.ts"
+
+const mockWeatherClient: WeatherKitClient = {
+	fetch: async () => ({}) as WeatherKitResponse,
+}
+
+describe("UserSessionManager", () => {
+	test("getOrCreate creates session on first call", () => {
+		const manager = new UserSessionManager([() => new LocationSource()])
+
+		const session = manager.getOrCreate("user-1")
+
+		expect(session).toBeDefined()
+		expect(session.engine).toBeDefined()
+	})
+
+	test("getOrCreate returns same session for same user", () => {
+		const manager = new UserSessionManager([() => new LocationSource()])
+
+		const session1 = manager.getOrCreate("user-1")
+		const session2 = manager.getOrCreate("user-1")
+
+		expect(session1).toBe(session2)
+	})
+
+	test("getOrCreate returns different sessions for different users", () => {
+		const manager = new UserSessionManager([() => new LocationSource()])
+
+		const session1 = manager.getOrCreate("user-1")
+		const session2 = manager.getOrCreate("user-2")
+
+		expect(session1).not.toBe(session2)
+	})
+
+	test("each user gets independent source instances", () => {
+		const manager = new UserSessionManager([() => new LocationSource()])
+
+		const session1 = manager.getOrCreate("user-1")
+		const session2 = manager.getOrCreate("user-2")
+
+		const source1 = session1.getSource<LocationSource>("aris.location")
+		const source2 = session2.getSource<LocationSource>("aris.location")
+
+		expect(source1).not.toBe(source2)
+	})
+
+	test("remove destroys session and allows re-creation", () => {
+		const manager = new UserSessionManager([() => new LocationSource()])
+
+		const session1 = manager.getOrCreate("user-1")
+		manager.remove("user-1")
+		const session2 = manager.getOrCreate("user-1")
+
+		expect(session1).not.toBe(session2)
+	})
+
+	test("remove is no-op for unknown user", () => {
+		const manager = new UserSessionManager([() => new LocationSource()])
+
+		expect(() => manager.remove("unknown")).not.toThrow()
+	})
+
+	test("accepts function providers", async () => {
+		const manager = new UserSessionManager([() => new LocationSource()])
+
+		const session = manager.getOrCreate("user-1")
+		const result = await session.engine.refresh()
+
+		expect(result.errors).toHaveLength(0)
+	})
+
+	test("accepts object providers", () => {
+		const provider = new WeatherSourceProvider({ client: mockWeatherClient })
+		const manager = new UserSessionManager([() => new LocationSource(), provider])
+
+		const session = manager.getOrCreate("user-1")
+
+		expect(session.getSource("aris.weather")).toBeDefined()
+	})
+
+	test("accepts mixed providers", () => {
+		const provider = new WeatherSourceProvider({ client: mockWeatherClient })
+		const manager = new UserSessionManager([() => new LocationSource(), provider])
+
+		const session = manager.getOrCreate("user-1")
+
+		expect(session.getSource("aris.location")).toBeDefined()
+		expect(session.getSource("aris.weather")).toBeDefined()
+	})
+
+	test("refresh returns feed result through session", async () => {
+		const manager = new UserSessionManager([() => new LocationSource()])
+
+		const session = manager.getOrCreate("user-1")
+		const result = await session.engine.refresh()
+
+		expect(result).toHaveProperty("context")
+		expect(result).toHaveProperty("items")
+		expect(result).toHaveProperty("errors")
+		expect(result.context.time).toBeInstanceOf(Date)
+	})
+
+	test("location update via executeAction works", async () => {
+		const manager = new UserSessionManager([() => new LocationSource()])
+
+		const session = manager.getOrCreate("user-1")
+		await session.engine.executeAction("aris.location", "update-location", {
+			lat: 51.5074,
+			lng: -0.1278,
+			accuracy: 10,
+			timestamp: new Date(),
+		})
+
+		const source = session.getSource<LocationSource>("aris.location")
+		expect(source?.lastLocation?.lat).toBe(51.5074)
+	})
+
+	test("subscribe receives updates after location push", async () => {
+		const manager = new UserSessionManager([() => new LocationSource()])
+		const callback = mock()
+
+		const session = manager.getOrCreate("user-1")
+		session.engine.subscribe(callback)
+
+		await session.engine.executeAction("aris.location", "update-location", {
+			lat: 51.5074,
+			lng: -0.1278,
+			accuracy: 10,
+			timestamp: new Date(),
+		})
+
+		// Wait for async update propagation
+		await new Promise((resolve) => setTimeout(resolve, 10))
+
+		expect(callback).toHaveBeenCalled()
+	})
+
+	test("remove stops reactive updates", async () => {
+		const manager = new UserSessionManager([() => new LocationSource()])
+		const callback = mock()
+
+		const session = manager.getOrCreate("user-1")
+		session.engine.subscribe(callback)
+
+		manager.remove("user-1")
+
+		// Create new session and push location — old callback should not fire
+		const session2 = manager.getOrCreate("user-1")
+		await session2.engine.executeAction("aris.location", "update-location", {
+			lat: 51.5074,
+			lng: -0.1278,
+			accuracy: 10,
+			timestamp: new Date(),
+		})
+
+		await new Promise((resolve) => setTimeout(resolve, 10))
+
+		expect(callback).not.toHaveBeenCalled()
+	})
+})

apps/aris-backend/src/session/user-session-manager.ts

@@ -0,0 +1,32 @@
+import type { FeedSourceProviderInput } from "./feed-source-provider.ts"
+
+import { UserSession } from "./user-session.ts"
+
+export class UserSessionManager {
+	private sessions = new Map<string, UserSession>()
+	private readonly providers: FeedSourceProviderInput[]
+
+	constructor(providers: FeedSourceProviderInput[]) {
+		this.providers = providers
+	}
+
+	getOrCreate(userId: string): UserSession {
+		let session = this.sessions.get(userId)
+		if (!session) {
+			const sources = this.providers.map((p) =>
+				typeof p === "function" ? p(userId) : p.feedSourceForUser(userId),
+			)
+			session = new UserSession(sources)
+			this.sessions.set(userId, session)
+		}
+		return session
+	}
+
+	remove(userId: string): void {
+		const session = this.sessions.get(userId)
+		if (session) {
+			session.destroy()
+			this.sessions.delete(userId)
+		}
+	}
+}

apps/aris-backend/src/session/user-session.test.ts

@@ -0,0 +1,72 @@
+import type { ActionDefinition, Context, FeedSource } from "@aris/core"
+
+import { LocationSource } from "@aris/source-location"
+import { describe, expect, test } from "bun:test"
+
+import { UserSession } from "./user-session.ts"
+
+function createStubSource(id: string): FeedSource {
+	return {
+		id,
+		async listActions(): Promise<Record<string, ActionDefinition>> {
+			return {}
+		},
+		async executeAction(): Promise<unknown> {
+			return undefined
+		},
+		async fetchContext(): Promise<Partial<Context> | null> {
+			return null
+		},
+		async fetchItems() {
+			return []
+		},
+	}
+}
+
+describe("UserSession", () => {
+	test("registers sources and starts engine", async () => {
+		const session = new UserSession([createStubSource("test-a"), createStubSource("test-b")])
+
+		const result = await session.engine.refresh()
+
+		expect(result.errors).toHaveLength(0)
+	})
+
+	test("getSource returns registered source", () => {
+		const location = new LocationSource()
+		const session = new UserSession([location])
+
+		const result = session.getSource<LocationSource>("aris.location")
+
+		expect(result).toBe(location)
+	})
+
+	test("getSource returns undefined for unknown source", () => {
+		const session = new UserSession([createStubSource("test")])
+
+		expect(session.getSource("unknown")).toBeUndefined()
+	})
+
+	test("destroy stops engine and clears sources", () => {
+		const session = new UserSession([createStubSource("test")])
+
+		session.destroy()
+
+		expect(session.getSource("test")).toBeUndefined()
+	})
+
+	test("engine.executeAction routes to correct source", async () => {
+		const location = new LocationSource()
+		const session = new UserSession([location])
+
+		await session.engine.executeAction("aris.location", "update-location", {
+			lat: 51.5,
+			lng: -0.1,
+			accuracy: 10,
+			timestamp: new Date(),
+		})
+
+		expect(location.lastLocation).toBeDefined()
+		expect(location.lastLocation!.lat).toBe(51.5)
+	})
+})

apps/aris-backend/src/session/user-session.ts

@@ -0,0 +1,24 @@
+import { FeedEngine, type FeedSource } from "@aris/core"
+
+export class UserSession {
+	readonly engine: FeedEngine
+	private sources = new Map<string, FeedSource>()
+
+	constructor(sources: FeedSource[]) {
+		this.engine = new FeedEngine()
+		for (const source of sources) {
+			this.sources.set(source.id, source)
+			this.engine.register(source)
+		}
+		this.engine.start()
+	}
+
+	getSource<T extends FeedSource>(sourceId: string): T | undefined {
+		return this.sources.get(sourceId) as T | undefined
+	}
+
+	destroy(): void {
+		this.engine.stop()
+		this.sources.clear()
+	}
+}

apps/aris-backend/src/tfl/provider.ts

@@ -0,0 +1,19 @@
+import { TflSource, type ITflApi } from "@aris/source-tfl"
+
+import type { FeedSourceProvider } from "../session/feed-source-provider.ts"
+
+export type TflSourceProviderOptions =
+	| { apiKey: string; client?: never }
+	| { apiKey?: never; client: ITflApi }
+
+export class TflSourceProvider implements FeedSourceProvider {
+	private readonly options: TflSourceProviderOptions
+
+	constructor(options: TflSourceProviderOptions) {
+		this.options = options
+	}
+
+	feedSourceForUser(_userId: string): TflSource {
+		return new TflSource(this.options)
+	}
+}

apps/aris-backend/src/weather/provider.ts

@@ -0,0 +1,15 @@
+import { WeatherSource, type WeatherSourceOptions } from "@aris/source-weatherkit"
+
+import type { FeedSourceProvider } from "../session/feed-source-provider.ts"
+
+export class WeatherSourceProvider implements FeedSourceProvider {
+	private readonly options: WeatherSourceOptions
+
+	constructor(options: WeatherSourceOptions) {
+		this.options = options
+	}
+
+	feedSourceForUser(_userId: string): WeatherSource {
+		return new WeatherSource(this.options)
+	}
+}

apps/aris-client/.gitignore

@@ -0,0 +1,43 @@
+# Learn more https://docs.github.com/en/get-started/getting-started-with-git/ignoring-files
+
+# dependencies
+node_modules/
+
+# Expo
+.expo/
+dist/
+web-build/
+expo-env.d.ts
+
+# Native
+.kotlin/
+*.orig.*
+*.jks
+*.p8
+*.p12
+*.key
+*.mobileprovision
+
+# Metro
+.metro-health-check*
+
+# debug
+npm-debug.*
+yarn-debug.*
+yarn-error.*
+
+# macOS
+.DS_Store
+*.pem
+
+# local env files
+.env*.local
+
+# typescript
+*.tsbuildinfo
+
+app-example
+
+# generated native folders
+/ios
+/android

apps/aris-client/.vscode/extensions.json

@@ -0,0 +1 @@
+{ "recommendations": ["expo.vscode-expo-tools"] }

apps/aris-client/.vscode/settings.json

@@ -0,0 +1,7 @@
+{
+	"editor.codeActionsOnSave": {
+		"source.fixAll": "explicit",
+		"source.organizeImports": "explicit",
+		"source.sortMembers": "explicit"
+	}
+}

apps/aris-client/README.md

@@ -0,0 +1,50 @@
+# Welcome to your Expo app 👋
+
+This is an [Expo](https://expo.dev) project created with [`create-expo-app`](https://www.npmjs.com/package/create-expo-app).
+
+## Get started
+
+1. Install dependencies
+
+   ```bash
+   npm install
+   ```
+
+2. Start the app
+
+   ```bash
+   npx expo start
+   ```
+
+In the output, you'll find options to open the app in a
+
+- [development build](https://docs.expo.dev/develop/development-builds/introduction/)
+- [Android emulator](https://docs.expo.dev/workflow/android-studio-emulator/)
+- [iOS simulator](https://docs.expo.dev/workflow/ios-simulator/)
+- [Expo Go](https://expo.dev/go), a limited sandbox for trying out app development with Expo
+
+You can start developing by editing the files inside the **app** directory. This project uses [file-based routing](https://docs.expo.dev/router/introduction).
+
+## Get a fresh project
+
+When you're ready, run:
+
+```bash
+npm run reset-project
+```
+
+This command will move the starter code to the **app-example** directory and create a blank **app** directory where you can start developing.
+
+## Learn more
+
+To learn more about developing your project with Expo, look at the following resources:
+
+- [Expo documentation](https://docs.expo.dev/): Learn fundamentals, or go into advanced topics with our [guides](https://docs.expo.dev/guides).
+- [Learn Expo tutorial](https://docs.expo.dev/tutorial/introduction/): Follow a step-by-step tutorial where you'll create a project that runs on Android, iOS, and the web.
+
+## Join the community
+
+Join our community of developers creating universal apps.
+
+- [Expo on GitHub](https://github.com/expo/expo): View our open source platform and contribute.
+- [Discord community](https://chat.expo.dev): Chat with Expo users and ask questions.

apps/aris-client/app.json

@@ -0,0 +1,152 @@
+{
+	"expo": {
+		"name": "Aris",
+		"slug": "aris-client",
+		"version": "1.0.0",
+		"orientation": "portrait",
+		"icon": "./assets/images/icon.png",
+		"scheme": "aris",
+		"userInterfaceStyle": "automatic",
+		"newArchEnabled": true,
+		"ios": {
+			"infoPlist": {
+				"NSAppTransportSecurity": {
+					"NSAllowsArbitraryLoads": true
+				},
+				"ITSAppUsesNonExemptEncryption": false
+			},
+			"bundleIdentifier": "sh.nym.aris"
+		},
+		"android": {
+			"adaptiveIcon": {
+				"backgroundColor": "#E6F4FE",
+				"foregroundImage": "./assets/images/android-icon-foreground.png",
+				"backgroundImage": "./assets/images/android-icon-background.png",
+				"monochromeImage": "./assets/images/android-icon-monochrome.png"
+			},
+			"edgeToEdgeEnabled": true,
+			"predictiveBackGestureEnabled": false,
+			"package": "sh.nym.aris"
+		},
+		"web": {
+			"output": "static",
+			"favicon": "./assets/images/favicon.png"
+		},
+		"plugins": [
+			"expo-router",
+			[
+				"expo-splash-screen",
+				{
+					"image": "./assets/images/splash-icon.png",
+					"imageWidth": 200,
+					"resizeMode": "contain",
+					"backgroundColor": "#ffffff",
+					"dark": {
+						"backgroundColor": "#000000"
+					}
+				}
+			],
+			[
+				"expo-font",
+				{
+					"android": {
+						"fonts": [
+							{
+								"fontFamily": "Inter",
+								"fontDefinitions": [
+									{ "path": "./assets/fonts/Inter_100Thin.ttf", "weight": 100 },
+									{ "path": "./assets/fonts/Inter_100Thin_Italic.ttf", "weight": 100, "style": "italic" },
+									{ "path": "./assets/fonts/Inter_200ExtraLight.ttf", "weight": 200 },
+									{ "path": "./assets/fonts/Inter_200ExtraLight_Italic.ttf", "weight": 200, "style": "italic" },
+									{ "path": "./assets/fonts/Inter_300Light.ttf", "weight": 300 },
+									{ "path": "./assets/fonts/Inter_300Light_Italic.ttf", "weight": 300, "style": "italic" },
+									{ "path": "./assets/fonts/Inter_400Regular.ttf", "weight": 400 },
+									{ "path": "./assets/fonts/Inter_400Regular_Italic.ttf", "weight": 400, "style": "italic" },
+									{ "path": "./assets/fonts/Inter_500Medium.ttf", "weight": 500 },
+									{ "path": "./assets/fonts/Inter_500Medium_Italic.ttf", "weight": 500, "style": "italic" },
+									{ "path": "./assets/fonts/Inter_600SemiBold.ttf", "weight": 600 },
+									{ "path": "./assets/fonts/Inter_600SemiBold_Italic.ttf", "weight": 600, "style": "italic" },
+									{ "path": "./assets/fonts/Inter_700Bold.ttf", "weight": 700 },
+									{ "path": "./assets/fonts/Inter_700Bold_Italic.ttf", "weight": 700, "style": "italic" },
+									{ "path": "./assets/fonts/Inter_800ExtraBold.ttf", "weight": 800 },
+									{ "path": "./assets/fonts/Inter_800ExtraBold_Italic.ttf", "weight": 800, "style": "italic" },
+									{ "path": "./assets/fonts/Inter_900Black.ttf", "weight": 900 },
+									{ "path": "./assets/fonts/Inter_900Black_Italic.ttf", "weight": 900, "style": "italic" }
+								]
+							},
+							{
+								"fontFamily": "Source Serif 4",
+								"fontDefinitions": [
+									{ "path": "./assets/fonts/SourceSerif4_200ExtraLight.ttf", "weight": 200 },
+									{ "path": "./assets/fonts/SourceSerif4_200ExtraLight_Italic.ttf", "weight": 200, "style": "italic" },
+									{ "path": "./assets/fonts/SourceSerif4_300Light.ttf", "weight": 300 },
+									{ "path": "./assets/fonts/SourceSerif4_300Light_Italic.ttf", "weight": 300, "style": "italic" },
+									{ "path": "./assets/fonts/SourceSerif4_400Regular.ttf", "weight": 400 },
+									{ "path": "./assets/fonts/SourceSerif4_400Regular_Italic.ttf", "weight": 400, "style": "italic" },
+									{ "path": "./assets/fonts/SourceSerif4_500Medium.ttf", "weight": 500 },
+									{ "path": "./assets/fonts/SourceSerif4_500Medium_Italic.ttf", "weight": 500, "style": "italic" },
+									{ "path": "./assets/fonts/SourceSerif4_600SemiBold.ttf", "weight": 600 },
+									{ "path": "./assets/fonts/SourceSerif4_600SemiBold_Italic.ttf", "weight": 600, "style": "italic" },
+									{ "path": "./assets/fonts/SourceSerif4_700Bold.ttf", "weight": 700 },
+									{ "path": "./assets/fonts/SourceSerif4_700Bold_Italic.ttf", "weight": 700, "style": "italic" },
+									{ "path": "./assets/fonts/SourceSerif4_800ExtraBold.ttf", "weight": 800 },
+									{ "path": "./assets/fonts/SourceSerif4_800ExtraBold_Italic.ttf", "weight": 800, "style": "italic" },
+									{ "path": "./assets/fonts/SourceSerif4_900Black.ttf", "weight": 900 },
+									{ "path": "./assets/fonts/SourceSerif4_900Black_Italic.ttf", "weight": 900, "style": "italic" }
+								]
+							}
+						]
+					},
+					"ios": {
+						"fonts": [
+							"./assets/fonts/Inter_100Thin.ttf",
+							"./assets/fonts/Inter_100Thin_Italic.ttf",
+							"./assets/fonts/Inter_200ExtraLight.ttf",
+							"./assets/fonts/Inter_200ExtraLight_Italic.ttf",
+							"./assets/fonts/Inter_300Light.ttf",
+							"./assets/fonts/Inter_300Light_Italic.ttf",
+							"./assets/fonts/Inter_400Regular.ttf",
+							"./assets/fonts/Inter_400Regular_Italic.ttf",
+							"./assets/fonts/Inter_500Medium.ttf",
+							"./assets/fonts/Inter_500Medium_Italic.ttf",
+							"./assets/fonts/Inter_600SemiBold.ttf",
+							"./assets/fonts/Inter_600SemiBold_Italic.ttf",
+							"./assets/fonts/Inter_700Bold.ttf",
+							"./assets/fonts/Inter_700Bold_Italic.ttf",
+							"./assets/fonts/Inter_800ExtraBold.ttf",
+							"./assets/fonts/Inter_800ExtraBold_Italic.ttf",
+							"./assets/fonts/Inter_900Black.ttf",
+							"./assets/fonts/Inter_900Black_Italic.ttf",
+							"./assets/fonts/SourceSerif4_200ExtraLight.ttf",
+							"./assets/fonts/SourceSerif4_200ExtraLight_Italic.ttf",
+							"./assets/fonts/SourceSerif4_300Light.ttf",
+							"./assets/fonts/SourceSerif4_300Light_Italic.ttf",
+							"./assets/fonts/SourceSerif4_400Regular.ttf",
+							"./assets/fonts/SourceSerif4_400Regular_Italic.ttf",
+							"./assets/fonts/SourceSerif4_500Medium.ttf",
+							"./assets/fonts/SourceSerif4_500Medium_Italic.ttf",
+							"./assets/fonts/SourceSerif4_600SemiBold.ttf",
+							"./assets/fonts/SourceSerif4_600SemiBold_Italic.ttf",
+							"./assets/fonts/SourceSerif4_700Bold.ttf",
+							"./assets/fonts/SourceSerif4_700Bold_Italic.ttf",
+							"./assets/fonts/SourceSerif4_800ExtraBold.ttf",
+							"./assets/fonts/SourceSerif4_800ExtraBold_Italic.ttf",
+							"./assets/fonts/SourceSerif4_900Black.ttf",
+							"./assets/fonts/SourceSerif4_900Black_Italic.ttf"
+						]
+					}
+				}
+			]
+		],
+		"experiments": {
+			"typedRoutes": true,
+			"reactCompiler": true
+		},
+		"extra": {
+			"router": {},
+			"eas": {
+				"projectId": "61092d23-36aa-418e-929d-ea40dc912e8f"
+			}
+		}
+	}
+}

apps/aris-client/eas.json

@@ -0,0 +1,27 @@
+{
+	"cli": {
+		"version": ">= 18.0.1",
+		"appVersionSource": "remote"
+	},
+	"build": {
+		"development": {
+			"developmentClient": true,
+			"distribution": "internal"
+		},
+		"development-simulator": {
+			"extends": "development",
+			"ios": {
+				"simulator": "true"
+			}
+		},
+		"preview": {
+			"distribution": "internal"
+		},
+		"production": {
+			"autoIncrement": true
+		}
+	},
+	"submit": {
+		"production": {}
+	}
+}

apps/aris-client/eslint.config.js

@@ -0,0 +1,10 @@
+// https://docs.expo.dev/guides/using-eslint/
+const { defineConfig } = require("eslint/config")
+const expoConfig = require("eslint-config-expo/flat")
+
+module.exports = defineConfig([
+	expoConfig,
+	{
+		ignores: ["dist/*"],
+	},
+])

apps/aris-client/package.json

@@ -0,0 +1,57 @@
+{
+	"name": "aris-client",
+	"version": "1.0.0",
+	"private": true,
+	"main": "expo-router/entry",
+	"scripts": {
+		"start": "./scripts/run-dev-server.sh",
+		"reset-project": "node ./scripts/reset-project.js",
+		"android": "expo start --android",
+		"ios": "expo start --ios",
+		"web": "expo start --web",
+		"lint": "expo lint",
+		"build:ios": "eas build --profile development --platform ios --non-interactive",
+		"build:ios-simulator": "eas build --profile development-simulator --platform ios --non-interactive",
+		"debugger": "bun run scripts/open-debugger.ts"
+	},
+	"dependencies": {
+		"@expo-google-fonts/inter": "^0.4.2",
+		"@expo-google-fonts/source-serif-4": "^0.4.1",
+		"@expo/vector-icons": "^15.0.3",
+		"@react-navigation/bottom-tabs": "^7.4.0",
+		"@react-navigation/elements": "^2.6.3",
+		"@react-navigation/native": "^7.1.8",
+		"expo": "~54.0.33",
+		"expo-constants": "~18.0.13",
+		"expo-dev-client": "~6.0.20",
+		"expo-font": "~14.0.11",
+		"expo-haptics": "~15.0.8",
+		"expo-image": "~3.0.11",
+		"expo-linking": "~8.0.11",
+		"expo-location": "~19.0.8",
+		"expo-router": "~6.0.23",
+		"expo-splash-screen": "~31.0.13",
+		"expo-status-bar": "~3.0.9",
+		"expo-symbols": "~1.0.8",
+		"expo-system-ui": "~6.0.9",
+		"expo-web-browser": "~15.0.10",
+		"react": "19.1.0",
+		"react-dom": "19.1.0",
+		"react-native": "0.81.5",
+		"react-native-gesture-handler": "~2.28.0",
+		"react-native-reanimated": "~4.1.1",
+		"react-native-safe-area-context": "~5.6.0",
+		"react-native-screens": "~4.16.0",
+		"react-native-svg": "15.12.1",
+		"react-native-web": "~0.21.0",
+		"react-native-worklets": "0.5.1",
+		"twrnc": "^4.16.0"
+	},
+	"devDependencies": {
+		"@types/react": "~19.1.0",
+		"eas-cli": "^18.0.1",
+		"eslint": "^9.25.0",
+		"eslint-config-expo": "~10.0.0",
+		"typescript": "~5.9.2"
+	}
+}

apps/aris-client/scripts/dev-proxy.ts

@@ -0,0 +1,127 @@
+// Reverse proxy that sits in front of Metro so that all requests
+// (including those arriving via Tailscale or Ona port-forwarding) reach
+// Metro as loopback connections. This satisfies the isLocalSocket check
+// in Expo's debug middleware, making /debugger-frontend, /json, and
+// /open-debugger accessible from a remote browser.
+
+import type { ServerWebSocket } from "bun"
+
+const PROXY_PORT = parseInt(process.env.PROXY_PORT || "8080", 10)
+const METRO_PORT = parseInt(process.env.METRO_PORT || "8081", 10)
+const METRO_BASE = `http://127.0.0.1:${METRO_PORT}`
+
+function forwardHeaders(headers: Headers): Headers {
+	const result = new Headers(headers)
+	result.delete("origin")
+	result.delete("referer")
+	result.set("host", `127.0.0.1:${METRO_PORT}`)
+	return result
+}
+
+interface WsData {
+	upstream: WebSocket
+	isDevice: boolean
+}
+
+Bun.serve<WsData>({
+	port: PROXY_PORT,
+
+	async fetch(req, server) {
+		const url = new URL(req.url)
+
+		// WebSocket upgrade — bridge to Metro's ws endpoint
+		if (req.headers.get("upgrade")?.toLowerCase() === "websocket") {
+			const wsUrl = `ws://127.0.0.1:${METRO_PORT}${url.pathname}${url.search}`
+			const upstream = new WebSocket(wsUrl)
+
+			// Wait for upstream to connect before upgrading the client
+			try {
+				await new Promise<void>((resolve, reject) => {
+					upstream.addEventListener("open", () => resolve())
+					upstream.addEventListener("error", () => reject(new Error("upstream ws failed")))
+				})
+			} catch {
+				return new Response("Upstream WebSocket unavailable", { status: 502 })
+			}
+
+			const isDevice = url.pathname.startsWith("/inspector/device")
+			const ok = server.upgrade(req, { data: { upstream, isDevice } })
+			if (!ok) {
+				upstream.close()
+				return new Response("WebSocket upgrade failed", { status: 500 })
+			}
+			return undefined
+		}
+
+		// HTTP proxy
+		const upstream = `${METRO_BASE}${url.pathname}${url.search}`
+		const res = await fetch(upstream, {
+			method: req.method,
+			headers: forwardHeaders(req.headers),
+			body: req.body,
+			redirect: "manual",
+		})
+
+		return new Response(res.body, {
+			status: res.status,
+			statusText: res.statusText,
+			headers: res.headers,
+		})
+	},
+
+	websocket: {
+		message(ws: ServerWebSocket<WsData>, msg) {
+			ws.data.upstream.send(msg)
+		},
+		open(ws: ServerWebSocket<WsData>) {
+			const { upstream } = ws.data
+			upstream.addEventListener("message", (ev) => {
+				if (typeof ev.data === "string") {
+					ws.send(ev.data)
+				} else if (ev.data instanceof ArrayBuffer) {
+					ws.sendBinary(new Uint8Array(ev.data))
+				}
+			})
+			upstream.addEventListener("close", () => ws.close())
+			upstream.addEventListener("error", () => ws.close())
+
+			// Print debugger URL shortly after a device connects,
+			// giving Metro time to register the target.
+			if (ws.data.isDevice) {
+				setTimeout(() => printDebuggerUrl(), 1000)
+			}
+		},
+		close(ws: ServerWebSocket<WsData>) {
+			ws.data.upstream.close()
+		},
+	},
+})
+
+const tsIp = await Bun.$`tailscale ip -4`.text().then((s) => s.trim())
+
+async function printDebuggerUrl() {
+	const base = `http://${tsIp}:${PROXY_PORT}`
+	const res = await fetch(`${METRO_BASE}/json`)
+	if (!res.ok) return
+
+	interface DebugTarget {
+		webSocketDebuggerUrl: string
+		reactNative?: {
+			capabilities?: { prefersFuseboxFrontend?: boolean }
+		}
+	}
+
+	const targets: DebugTarget[] = await res.json()
+	const target = targets.find((t) => t.reactNative?.capabilities?.prefersFuseboxFrontend)
+	if (!target) return
+
+	const wsPath = target.webSocketDebuggerUrl
+		.replace(/^ws:\/\//, "")
+		.replace(`127.0.0.1:${METRO_PORT}`, `${tsIp}:${PROXY_PORT}`)
+
+	console.log(
+		`\n  React Native DevTools:\n  ${base}/debugger-frontend/rn_fusebox.html?ws=${encodeURIComponent(wsPath)}&sources.hide_add_folder=true&unstable_enableNetworkPanel=true\n`,
+	)
+}
+
+console.log(`[proxy] listening on :${PROXY_PORT}, forwarding to 127.0.0.1:${METRO_PORT}`)

apps/aris-client/scripts/open-debugger.ts

@@ -0,0 +1,52 @@
+// Opens React Native DevTools in Chrome, connected to the first
+// available Hermes debug target. Requires Metro + proxy to be running.
+
+import { $ } from "bun"
+
+const PROXY_PORT = process.env.PROXY_PORT || "8080"
+const METRO_PORT = process.env.METRO_PORT || "8081"
+const tsIp = (await $`tailscale ip -4`.text()).trim()
+const base = `http://${tsIp}:${PROXY_PORT}`
+
+interface DebugTarget {
+	devtoolsFrontendUrl: string
+	webSocketDebuggerUrl: string
+	reactNative?: {
+		capabilities?: {
+			prefersFuseboxFrontend?: boolean
+		}
+	}
+}
+
+const res = await fetch(`${base}/json`)
+if (!res.ok) {
+	console.error("Failed to fetch /json — is Metro running?")
+	process.exit(1)
+}
+
+const targets: DebugTarget[] = await res.json()
+const target = targets.find((t) => t.reactNative?.capabilities?.prefersFuseboxFrontend)
+
+if (!target) {
+	console.error("No debug target found. Is the app connected?")
+	process.exit(1)
+}
+
+const wsUrl = target.webSocketDebuggerUrl
+	.replace(/^ws:\/\//, "")
+	.replace(`127.0.0.1:${METRO_PORT}`, `${tsIp}:${PROXY_PORT}`)
+
+const url = `${base}/debugger-frontend/rn_fusebox.html?ws=${encodeURIComponent(wsUrl)}&sources.hide_add_folder=true&unstable_enableNetworkPanel=true`
+
+console.log(url)
+
+// Open in Chrome app mode if on macOS
+try {
+	await $`open -a "Google Chrome" --args --app=${url}`.quiet()
+} catch {
+	try {
+		await $`xdg-open ${url}`.quiet()
+	} catch {
+		console.log("Open the URL above in Chrome.")
+	}
+}

apps/aris-client/scripts/reset-project.js

@@ -0,0 +1,112 @@
+#!/usr/bin/env node
+
+/**
+ * This script is used to reset the project to a blank state.
+ * It deletes or moves the /app, /components, /hooks, /scripts, and /constants directories to /app-example based on user input and creates a new /app directory with an index.tsx and _layout.tsx file.
+ * You can remove the `reset-project` script from package.json and safely delete this file after running it.
+ */
+
+const fs = require("fs")
+const path = require("path")
+const readline = require("readline")
+
+const root = process.cwd()
+const oldDirs = ["app", "components", "hooks", "constants", "scripts"]
+const exampleDir = "app-example"
+const newAppDir = "app"
+const exampleDirPath = path.join(root, exampleDir)
+
+const indexContent = `import { Text, View } from "react-native";
+
+export default function Index() {
+  return (
+    <View
+      style={{
+        flex: 1,
+        justifyContent: "center",
+        alignItems: "center",
+      }}
+    >
+      <Text>Edit app/index.tsx to edit this screen.</Text>
+    </View>
+  );
+}
+`
+
+const layoutContent = `import { Stack } from "expo-router";
+
+export default function RootLayout() {
+  return <Stack />;
+}
+`
+
+const rl = readline.createInterface({
+	input: process.stdin,
+	output: process.stdout,
+})
+
+const moveDirectories = async (userInput) => {
+	try {
+		if (userInput === "y") {
+			// Create the app-example directory
+			await fs.promises.mkdir(exampleDirPath, { recursive: true })
+			console.log(`📁 /${exampleDir} directory created.`)
+		}
+
+		// Move old directories to new app-example directory or delete them
+		for (const dir of oldDirs) {
+			const oldDirPath = path.join(root, dir)
+			if (fs.existsSync(oldDirPath)) {
+				if (userInput === "y") {
+					const newDirPath = path.join(root, exampleDir, dir)
+					await fs.promises.rename(oldDirPath, newDirPath)
+					console.log(`➡️ /${dir} moved to /${exampleDir}/${dir}.`)
+				} else {
+					await fs.promises.rm(oldDirPath, { recursive: true, force: true })
+					console.log(`❌ /${dir} deleted.`)
+				}
+			} else {
+				console.log(`➡️ /${dir} does not exist, skipping.`)
+			}
+		}
+
+		// Create new /app directory
+		const newAppDirPath = path.join(root, newAppDir)
+		await fs.promises.mkdir(newAppDirPath, { recursive: true })
+		console.log("\n📁 New /app directory created.")
+
+		// Create index.tsx
+		const indexPath = path.join(newAppDirPath, "index.tsx")
+		await fs.promises.writeFile(indexPath, indexContent)
+		console.log("📄 app/index.tsx created.")
+
+		// Create _layout.tsx
+		const layoutPath = path.join(newAppDirPath, "_layout.tsx")
+		await fs.promises.writeFile(layoutPath, layoutContent)
+		console.log("📄 app/_layout.tsx created.")
+
+		console.log("\n✅ Project reset complete. Next steps:")
+		console.log(
+			`1. Run \`npx expo start\` to start a development server.\n2. Edit app/index.tsx to edit the main screen.${
+				userInput === "y"
+					? `\n3. Delete the /${exampleDir} directory when you're done referencing it.`
+					: ""
+			}`,
+		)
+	} catch (error) {
+		console.error(`❌ Error during script execution: ${error.message}`)
+	}
+}
+
+rl.question(
+	"Do you want to move existing files to /app-example instead of deleting them? (Y/n): ",
+	(answer) => {
+		const userInput = answer.trim().toLowerCase() || "y"
+		if (userInput === "y" || userInput === "n") {
+			moveDirectories(userInput).finally(() => rl.close())
+		} else {
+			console.log("❌ Invalid input. Please enter 'Y' or 'N'.")
+			rl.close()
+		}
+	},
+)

apps/aris-client/scripts/run-dev-server.sh

@@ -0,0 +1,15 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+PROXY_PORT=8080
+METRO_PORT=8081
+
+# Start a reverse proxy so Metro sees all requests as loopback.
+# This makes debugger endpoints (/debugger-frontend, /json, /open-debugger)
+# accessible through the Tailscale IP.
+PROXY_PORT=$PROXY_PORT METRO_PORT=$METRO_PORT bun run scripts/dev-proxy.ts &
+PROXY_PID=$!
+trap "kill $PROXY_PID 2>/dev/null" EXIT
+
+EXPO_PACKAGER_PROXY_URL=http://$(tailscale ip -4):$PROXY_PORT bunx expo start --localhost -p $METRO_PORT
+

apps/aris-client/src/app/(tabs)/_layout.tsx

@@ -0,0 +1,36 @@
+import { Tabs } from "expo-router"
+import React from "react"
+
+import { HapticTab } from "@/components/haptic-tab"
+import { IconSymbol } from "@/components/ui/icon-symbol"
+import { Colors } from "@/constants/theme"
+import { useColorScheme } from "@/hooks/use-color-scheme"
+
+export default function TabLayout() {
+	const colorScheme = useColorScheme()
+
+	return (
+		<Tabs
+			screenOptions={{
+				tabBarActiveTintColor: Colors[colorScheme ?? "light"].tint,
+				headerShown: false,
+				tabBarButton: HapticTab,
+			}}
+		>
+			<Tabs.Screen
+				name="index"
+				options={{
+					title: "Home",
+					tabBarIcon: ({ color }) => <IconSymbol size={28} name="house.fill" color={color} />,
+				}}
+			/>
+			<Tabs.Screen
+				name="explore"
+				options={{
+					title: "Explore",
+					tabBarIcon: ({ color }) => <IconSymbol size={28} name="paperplane.fill" color={color} />,
+				}}
+			/>
+		</Tabs>
+	)
+}

apps/aris-client/src/app/(tabs)/explore.tsx

@@ -0,0 +1,114 @@
+import { Image } from "expo-image"
+import { Platform, StyleSheet } from "react-native"
+
+import { ExternalLink } from "@/components/external-link"
+import ParallaxScrollView from "@/components/parallax-scroll-view"
+import { ThemedText } from "@/components/themed-text"
+import { ThemedView } from "@/components/themed-view"
+import { Collapsible } from "@/components/ui/collapsible"
+import { IconSymbol } from "@/components/ui/icon-symbol"
+import { Fonts } from "@/constants/theme"
+
+export default function TabTwoScreen() {
+	return (
+		<ParallaxScrollView
+			headerBackgroundColor={{ light: "#D0D0D0", dark: "#353636" }}
+			headerImage={
+				<IconSymbol
+					size={310}
+					color="#808080"
+					name="chevron.left.forwardslash.chevron.right"
+					style={styles.headerImage}
+				/>
+			}
+		>
+			<ThemedView style={styles.titleContainer}>
+				<ThemedText
+					type="title"
+					style={{
+						fontFamily: Fonts.rounded,
+					}}
+				>
+					Explore
+				</ThemedText>
+			</ThemedView>
+			<ThemedText>This app includes example code to help you get started.</ThemedText>
+			<Collapsible title="File-based routing">
+				<ThemedText>
+					This app has two screens:{" "}
+					<ThemedText type="defaultSemiBold">app/(tabs)/index.tsx</ThemedText> and{" "}
+					<ThemedText type="defaultSemiBold">app/(tabs)/explore.tsx</ThemedText>
+				</ThemedText>
+				<ThemedText>
+					The layout file in <ThemedText type="defaultSemiBold">app/(tabs)/_layout.tsx</ThemedText>{" "}
+					sets up the tab navigator.
+				</ThemedText>
+				<ExternalLink href="https://docs.expo.dev/router/introduction">
+					<ThemedText type="link">Learn more</ThemedText>
+				</ExternalLink>
+			</Collapsible>
+			<Collapsible title="Android, iOS, and web support">
+				<ThemedText>
+					You can open this project on Android, iOS, and the web. To open the web version, press{" "}
+					<ThemedText type="defaultSemiBold">w</ThemedText> in the terminal running this project.
+				</ThemedText>
+			</Collapsible>
+			<Collapsible title="Images">
+				<ThemedText>
+					For static images, you can use the <ThemedText type="defaultSemiBold">@2x</ThemedText> and{" "}
+					<ThemedText type="defaultSemiBold">@3x</ThemedText> suffixes to provide files for
+					different screen densities
+				</ThemedText>
+				<Image
+					source={require("@assets/images/react-logo.png")}
+					style={{ width: 100, height: 100, alignSelf: "center" }}
+				/>
+				<ExternalLink href="https://reactnative.dev/docs/images">
+					<ThemedText type="link">Learn more</ThemedText>
+				</ExternalLink>
+			</Collapsible>
+			<Collapsible title="Light and dark mode components">
+				<ThemedText>
+					This template has light and dark mode support. The{" "}
+					<ThemedText type="defaultSemiBold">useColorScheme()</ThemedText> hook lets you inspect
+					what the user&apos;s current color scheme is, and so you can adjust UI colors accordingly.
+				</ThemedText>
+				<ExternalLink href="https://docs.expo.dev/develop/user-interface/color-themes/">
+					<ThemedText type="link">Learn more</ThemedText>
+				</ExternalLink>
+			</Collapsible>
+			<Collapsible title="Animations">
+				<ThemedText>
+					This template includes an example of an animated component. The{" "}
+					<ThemedText type="defaultSemiBold">components/HelloWave.tsx</ThemedText> component uses
+					the powerful{" "}
+					<ThemedText type="defaultSemiBold" style={{ fontFamily: Fonts.mono }}>
+						react-native-reanimated
+					</ThemedText>{" "}
+					library to create a waving hand animation.
+				</ThemedText>
+				{Platform.select({
+					ios: (
+						<ThemedText>
+							The <ThemedText type="defaultSemiBold">components/ParallaxScrollView.tsx</ThemedText>{" "}
+							component provides a parallax effect for the header image.
+						</ThemedText>
+					),
+				})}
+			</Collapsible>
+		</ParallaxScrollView>
+	)
+}
+
+const styles = StyleSheet.create({
+	headerImage: {
+		color: "#808080",
+		bottom: -90,
+		left: -35,
+		position: "absolute",
+	},
+	titleContainer: {
+		flexDirection: "row",
+		gap: 8,
+	},
+})

apps/aris-client/src/app/(tabs)/index.tsx

@@ -0,0 +1,96 @@
+import { Image } from "expo-image"
+import { Link } from "expo-router"
+import { Platform, StyleSheet } from "react-native"
+
+import { HelloWave } from "@/components/hello-wave"
+import ParallaxScrollView from "@/components/parallax-scroll-view"
+import { ThemedText } from "@/components/themed-text"
+import { ThemedView } from "@/components/themed-view"
+
+export default function HomeScreen() {
+	return (
+		<ParallaxScrollView
+			headerBackgroundColor={{ light: "#A1CEDC", dark: "#1D3D47" }}
+			headerImage={
+				<Image source={require("@assets/images/partial-react-logo.png")} style={styles.reactLogo} />
+			}
+		>
+			<ThemedView style={styles.titleContainer}>
+				<ThemedText type="title">Welcome!</ThemedText>
+				<HelloWave />
+			</ThemedView>
+			<ThemedView style={styles.stepContainer}>
+				<ThemedText type="subtitle">Step 1: Try it</ThemedText>
+				<ThemedText>
+					Edit <ThemedText type="defaultSemiBold">app/(tabs)/index.tsx</ThemedText> to see changes.
+					Press{" "}
+					<ThemedText type="defaultSemiBold">
+						{Platform.select({
+							ios: "cmd + d",
+							android: "cmd + m",
+							web: "F12",
+						})}
+					</ThemedText>{" "}
+					to open developer tools.
+				</ThemedText>
+			</ThemedView>
+			<ThemedView style={styles.stepContainer}>
+				<Link href="/modal">
+					<Link.Trigger>
+						<ThemedText type="subtitle">Step 2: Explore</ThemedText>
+					</Link.Trigger>
+					<Link.Preview />
+					<Link.Menu>
+						<Link.MenuAction title="Action" icon="cube" onPress={() => alert("Action pressed")} />
+						<Link.MenuAction
+							title="Share"
+							icon="square.and.arrow.up"
+							onPress={() => alert("Share pressed")}
+						/>
+						<Link.Menu title="More" icon="ellipsis">
+							<Link.MenuAction
+								title="Delete"
+								icon="trash"
+								destructive
+								onPress={() => alert("Delete pressed")}
+							/>
+						</Link.Menu>
+					</Link.Menu>
+				</Link>
+
+				<ThemedText>
+					{`Tap the Explore tab to learn more about what's included in this starter app.`}
+				</ThemedText>
+			</ThemedView>
+			<ThemedView style={styles.stepContainer}>
+				<ThemedText type="subtitle">Step 3: Get a fresh start</ThemedText>
+				<ThemedText>
+					{`When you're ready, run `}
+					<ThemedText type="defaultSemiBold">npm run reset-project</ThemedText> to get a fresh{" "}
+					<ThemedText type="defaultSemiBold">app</ThemedText> directory. This will move the current{" "}
+					<ThemedText type="defaultSemiBold">app</ThemedText> to{" "}
+					<ThemedText type="defaultSemiBold">app-example</ThemedText>.
+				</ThemedText>
+			</ThemedView>
+		</ParallaxScrollView>
+	)
+}
+
+const styles = StyleSheet.create({
+	titleContainer: {
+		flexDirection: "row",
+		alignItems: "center",
+		gap: 8,
+	},
+	stepContainer: {
+		gap: 8,
+		marginBottom: 8,
+	},
+	reactLogo: {
+		height: 178,
+		width: 290,
+		bottom: 0,
+		left: 0,
+		position: "absolute",
+	},
+})

apps/aris-client/src/app/_layout.tsx

@@ -0,0 +1,23 @@
+import { DarkTheme, DefaultTheme, ThemeProvider } from "@react-navigation/native"
+import { Stack } from "expo-router"
+import { StatusBar } from "expo-status-bar"
+import "react-native-reanimated"
+import { useColorScheme } from "@/hooks/use-color-scheme"
+
+export const unstable_settings = {
+	anchor: "(tabs)",
+}
+
+export default function RootLayout() {
+	const colorScheme = useColorScheme()
+
+	return (
+		<ThemeProvider value={colorScheme === "dark" ? DarkTheme : DefaultTheme}>
+			<Stack>
+				<Stack.Screen name="(tabs)" options={{ headerShown: false }} />
+				<Stack.Screen name="modal" options={{ presentation: "modal", title: "Modal" }} />
+			</Stack>
+			<StatusBar style="auto" />
+		</ThemeProvider>
+	)
+}

apps/aris-client/src/app/modal.tsx

@@ -0,0 +1,29 @@
+import { Link } from "expo-router"
+import { StyleSheet } from "react-native"
+
+import { ThemedText } from "@/components/themed-text"
+import { ThemedView } from "@/components/themed-view"
+
+export default function ModalScreen() {
+	return (
+		<ThemedView style={styles.container}>
+			<ThemedText type="title">This is a modal</ThemedText>
+			<Link href="/" dismissTo style={styles.link}>
+				<ThemedText type="link">Go to home screen</ThemedText>
+			</Link>
+		</ThemedView>
+	)
+}
+
+const styles = StyleSheet.create({
+	container: {
+		flex: 1,
+		alignItems: "center",
+		justifyContent: "center",
+		padding: 20,
+	},
+	link: {
+		marginTop: 15,
+		paddingVertical: 15,
+	},
+})

apps/aris-client/src/components/external-link.tsx

@@ -0,0 +1,25 @@
+import { Href, Link } from "expo-router"
+import { openBrowserAsync, WebBrowserPresentationStyle } from "expo-web-browser"
+import { type ComponentProps } from "react"
+
+type Props = Omit<ComponentProps<typeof Link>, "href"> & { href: Href & string }
+
+export function ExternalLink({ href, ...rest }: Props) {
+	return (
+		<Link
+			target="_blank"
+			{...rest}
+			href={href}
+			onPress={async (event) => {
+				if (process.env.EXPO_OS !== "web") {
+					// Prevent the default behavior of linking to the default browser on native.
+					event.preventDefault()
+					// Open the link in an in-app browser.
+					await openBrowserAsync(href, {
+						presentationStyle: WebBrowserPresentationStyle.AUTOMATIC,
+					})
+				}
+			}}
+		/>
+	)
+}

apps/aris-client/src/components/haptic-tab.tsx

@@ -0,0 +1,18 @@
+import { BottomTabBarButtonProps } from "@react-navigation/bottom-tabs"
+import { PlatformPressable } from "@react-navigation/elements"
+import * as Haptics from "expo-haptics"
+
+export function HapticTab(props: BottomTabBarButtonProps) {
+	return (
+		<PlatformPressable
+			{...props}
+			onPressIn={(ev) => {
+				if (process.env.EXPO_OS === "ios") {
+					// Add a soft haptic feedback when pressing down on the tabs.
+					Haptics.impactAsync(Haptics.ImpactFeedbackStyle.Light)
+				}
+				props.onPressIn?.(ev)
+			}}
+		/>
+	)
+}

apps/aris-client/src/components/hello-wave.tsx

@@ -0,0 +1,20 @@
+import Animated from "react-native-reanimated"
+
+export function HelloWave() {
+	return (
+		<Animated.Text
+			style={{
+				fontSize: 28,
+				lineHeight: 32,
+				marginTop: -6,
+				animationName: {
+					"50%": { transform: [{ rotate: "25deg" }] },
+				},
+				animationIterationCount: 4,
+				animationDuration: "300ms",
+			}}
+		>
+			👋
+		</Animated.Text>
+	)
+}

apps/aris-client/src/components/parallax-scroll-view.tsx

@@ -0,0 +1,82 @@
+import type { PropsWithChildren, ReactElement } from "react"
+
+import { StyleSheet } from "react-native"
+import Animated, {
+	interpolate,
+	useAnimatedRef,
+	useAnimatedStyle,
+	useScrollOffset,
+} from "react-native-reanimated"
+
+import { ThemedView } from "@/components/themed-view"
+import { useColorScheme } from "@/hooks/use-color-scheme"
+import { useThemeColor } from "@/hooks/use-theme-color"
+
+const HEADER_HEIGHT = 250
+
+type Props = PropsWithChildren<{
+	headerImage: ReactElement
+	headerBackgroundColor: { dark: string; light: string }
+}>
+
+export default function ParallaxScrollView({
+	children,
+	headerImage,
+	headerBackgroundColor,
+}: Props) {
+	const backgroundColor = useThemeColor({}, "background")
+	const colorScheme = useColorScheme() ?? "light"
+	const scrollRef = useAnimatedRef<Animated.ScrollView>()
+	const scrollOffset = useScrollOffset(scrollRef)
+	const headerAnimatedStyle = useAnimatedStyle(() => {
+		return {
+			transform: [
+				{
+					translateY: interpolate(
+						scrollOffset.value,
+						[-HEADER_HEIGHT, 0, HEADER_HEIGHT],
+						[-HEADER_HEIGHT / 2, 0, HEADER_HEIGHT * 0.75],
+					),
+				},
+				{
+					scale: interpolate(scrollOffset.value, [-HEADER_HEIGHT, 0, HEADER_HEIGHT], [2, 1, 1]),
+				},
+			],
+		}
+	})
+
+	return (
+		<Animated.ScrollView
+			ref={scrollRef}
+			style={{ backgroundColor, flex: 1 }}
+			scrollEventThrottle={16}
+		>
+			<Animated.View
+				style={[
+					styles.header,
+					{ backgroundColor: headerBackgroundColor[colorScheme] },
+					headerAnimatedStyle,
+				]}
+			>
+				{headerImage}
+			</Animated.View>
+			<ThemedView style={styles.content}>{children}</ThemedView>
+		</Animated.ScrollView>
+	)
+}
+
+const styles = StyleSheet.create({
+	container: {
+		flex: 1,
+	},
+	header: {
+		height: HEADER_HEIGHT,
+		overflow: "hidden",
+	},
+	content: {
+		flex: 1,
+		padding: 32,
+		gap: 16,
+		overflow: "hidden",
+	},
+})

apps/aris-client/src/components/themed-text.tsx

@@ -0,0 +1,60 @@
+import { StyleSheet, Text, type TextProps } from "react-native"
+
+import { useThemeColor } from "@/hooks/use-theme-color"
+
+export type ThemedTextProps = TextProps & {
+	lightColor?: string
+	darkColor?: string
+	type?: "default" | "title" | "defaultSemiBold" | "subtitle" | "link"
+}
+
+export function ThemedText({
+	style,
+	lightColor,
+	darkColor,
+	type = "default",
+	...rest
+}: ThemedTextProps) {
+	const color = useThemeColor({ light: lightColor, dark: darkColor }, "text")
+
+	return (
+		<Text
+			style={[
+				{ color },
+				type === "default" ? styles.default : undefined,
+				type === "title" ? styles.title : undefined,
+				type === "defaultSemiBold" ? styles.defaultSemiBold : undefined,
+				type === "subtitle" ? styles.subtitle : undefined,
+				type === "link" ? styles.link : undefined,
+				style,
+			]}
+			{...rest}
+		/>
+	)
+}
+
+const styles = StyleSheet.create({
+	default: {
+		fontSize: 16,
+		lineHeight: 24,
+	},
+	defaultSemiBold: {
+		fontSize: 16,
+		lineHeight: 24,
+		fontWeight: "600",
+	},
+	title: {
+		fontSize: 32,
+		fontWeight: "bold",
+		lineHeight: 32,
+	},
+	subtitle: {
+		fontSize: 20,
+		fontWeight: "bold",
+	},
+	link: {
+		lineHeight: 30,
+		fontSize: 16,
+		color: "#0a7ea4",
+	},
+})

apps/aris-client/src/components/themed-view.tsx

@@ -0,0 +1,14 @@
+import { View, type ViewProps } from "react-native"
+
+import { useThemeColor } from "@/hooks/use-theme-color"
+
+export type ThemedViewProps = ViewProps & {
+	lightColor?: string
+	darkColor?: string
+}
+
+export function ThemedView({ style, lightColor, darkColor, ...otherProps }: ThemedViewProps) {
+	const backgroundColor = useThemeColor({ light: lightColor, dark: darkColor }, "background")
+
+	return <View style={[{ backgroundColor }, style]} {...otherProps} />
+}

apps/aris-client/src/components/ui/collapsible.tsx

@@ -0,0 +1,46 @@
+import { PropsWithChildren, useState } from "react"
+import { StyleSheet, TouchableOpacity } from "react-native"
+
+import { ThemedText } from "@/components/themed-text"
+import { ThemedView } from "@/components/themed-view"
+import { IconSymbol } from "@/components/ui/icon-symbol"
+import { Colors } from "@/constants/theme"
+import { useColorScheme } from "@/hooks/use-color-scheme"
+
+export function Collapsible({ children, title }: PropsWithChildren & { title: string }) {
+	const [isOpen, setIsOpen] = useState(false)
+	const theme = useColorScheme() ?? "light"
+
+	return (
+		<ThemedView>
+			<TouchableOpacity
+				style={styles.heading}
+				onPress={() => setIsOpen((value) => !value)}
+				activeOpacity={0.8}
+			>
+				<IconSymbol
+					name="chevron.right"
+					size={18}
+					weight="medium"
+					color={theme === "light" ? Colors.light.icon : Colors.dark.icon}
+					style={{ transform: [{ rotate: isOpen ? "90deg" : "0deg" }] }}
+				/>
+
+				<ThemedText type="defaultSemiBold">{title}</ThemedText>
+			</TouchableOpacity>
+			{isOpen && <ThemedView style={styles.content}>{children}</ThemedView>}
+		</ThemedView>
+	)
+}
+
+const styles = StyleSheet.create({
+	heading: {
+		flexDirection: "row",
+		alignItems: "center",
+		gap: 6,
+	},
+	content: {
+		marginTop: 6,
+		marginLeft: 24,
+	},
+})

apps/aris-client/src/components/ui/icon-symbol.ios.tsx

@@ -0,0 +1,32 @@
+import { SymbolView, SymbolViewProps, SymbolWeight } from "expo-symbols"
+import { StyleProp, ViewStyle } from "react-native"
+
+export function IconSymbol({
+	name,
+	size = 24,
+	color,
+	style,
+	weight = "regular",
+}: {
+	name: SymbolViewProps["name"]
+	size?: number
+	color: string
+	style?: StyleProp<ViewStyle>
+	weight?: SymbolWeight
+}) {
+	return (
+		<SymbolView
+			weight={weight}
+			tintColor={color}
+			resizeMode="scaleAspectFit"
+			name={name}
+			style={[
+				{
+					width: size,
+					height: size,
+				},
+				style,
+			]}
+		/>
+	)
+}

apps/aris-client/src/components/ui/icon-symbol.tsx

@@ -0,0 +1,41 @@
+// Fallback for using MaterialIcons on Android and web.
+
+import MaterialIcons from "@expo/vector-icons/MaterialIcons"
+import { SymbolWeight, SymbolViewProps } from "expo-symbols"
+import { ComponentProps } from "react"
+import { OpaqueColorValue, type StyleProp, type TextStyle } from "react-native"
+
+type IconMapping = Record<SymbolViewProps["name"], ComponentProps<typeof MaterialIcons>["name"]>
+type IconSymbolName = keyof typeof MAPPING
+
+/**
+ * Add your SF Symbols to Material Icons mappings here.
+ * - see Material Icons in the [Icons Directory](https://icons.expo.fyi).
+ * - see SF Symbols in the [SF Symbols](https://developer.apple.com/sf-symbols/) app.
+ */
+const MAPPING = {
+	"house.fill": "home",
+	"paperplane.fill": "send",
+	"chevron.left.forwardslash.chevron.right": "code",
+	"chevron.right": "chevron-right",
+} as IconMapping
+
+/**
+ * An icon component that uses native SF Symbols on iOS, and Material Icons on Android and web.
+ * This ensures a consistent look across platforms, and optimal resource usage.
+ * Icon `name`s are based on SF Symbols and require manual mapping to Material Icons.
+ */
+export function IconSymbol({
+	name,
+	size = 24,
+	color,
+	style,
+}: {
+	name: IconSymbolName
+	size?: number
+	color: string | OpaqueColorValue
+	style?: StyleProp<TextStyle>
+	weight?: SymbolWeight
+}) {
+	return <MaterialIcons color={color} size={size} name={MAPPING[name]} style={style} />
+}

apps/aris-client/src/constants/theme.ts

@@ -0,0 +1,53 @@
+/**
+ * Below are the colors that are used in the app. The colors are defined in the light and dark mode.
+ * There are many other ways to style your app. For example, [Nativewind](https://www.nativewind.dev/), [unistyles](https://reactnativeunistyles.vercel.app), etc.
+ */
+
+import { Platform } from "react-native"
+
+const tintColorLight = "#0a7ea4"
+const tintColorDark = "#fff"
+
+export const Colors = {
+	light: {
+		text: "#11181C",
+		background: "#fff",
+		tint: tintColorLight,
+		icon: "#687076",
+		tabIconDefault: "#687076",
+		tabIconSelected: tintColorLight,
+	},
+	dark: {
+		text: "#ECEDEE",
+		background: "#151718",
+		tint: tintColorDark,
+		icon: "#9BA1A6",
+		tabIconDefault: "#9BA1A6",
+		tabIconSelected: tintColorDark,
+	},
+}
+
+export const Fonts = Platform.select({
+	ios: {
+		/** iOS `UIFontDescriptorSystemDesignDefault` */
+		sans: "system-ui",
+		/** iOS `UIFontDescriptorSystemDesignSerif` */
+		serif: "ui-serif",
+		/** iOS `UIFontDescriptorSystemDesignRounded` */
+		rounded: "ui-rounded",
+		/** iOS `UIFontDescriptorSystemDesignMonospaced` */
+		mono: "ui-monospace",
+	},
+	default: {
+		sans: "normal",
+		serif: "serif",
+		rounded: "normal",
+		mono: "monospace",
+	},
+	web: {
+		sans: "system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif",
+		serif: "Georgia, 'Times New Roman', serif",
+		rounded: "'SF Pro Rounded', 'Hiragino Maru Gothic ProN', Meiryo, 'MS PGothic', sans-serif",
+		mono: "SFMono-Regular, Menlo, Monaco, Consolas, 'Liberation Mono', 'Courier New', monospace",
+	},
+})

apps/aris-client/src/hooks/use-color-scheme.ts

@@ -0,0 +1 @@
+export { useColorScheme } from "react-native"

apps/aris-client/src/hooks/use-color-scheme.web.ts

@@ -0,0 +1,21 @@
+import { useEffect, useState } from "react"
+import { useColorScheme as useRNColorScheme } from "react-native"
+
+/**
+ * To support static rendering, this value needs to be re-calculated on the client side for web
+ */
+export function useColorScheme() {
+	const [hasHydrated, setHasHydrated] = useState(false)
+
+	useEffect(() => {
+		setHasHydrated(true)
+	}, [])
+
+	const colorScheme = useRNColorScheme()
+
+	if (hasHydrated) {
+		return colorScheme
+	}
+
+	return "light"
+}

apps/aris-client/src/hooks/use-theme-color.ts

@@ -0,0 +1,21 @@
+/**
+ * Learn more about light and dark modes:
+ * https://docs.expo.dev/guides/color-schemes/
+ */
+
+import { Colors } from "@/constants/theme"
+import { useColorScheme } from "@/hooks/use-color-scheme"
+
+export function useThemeColor(
+	props: { light?: string; dark?: string },
+	colorName: keyof typeof Colors.light & keyof typeof Colors.dark,
+) {
+	const theme = useColorScheme() ?? "light"
+	const colorFromProps = props[theme]
+
+	if (colorFromProps) {
+		return colorFromProps
+	} else {
+		return Colors[theme][colorName]
+	}
+}

apps/aris-client/tsconfig.json

@@ -0,0 +1,11 @@
+{
+	"extends": "expo/tsconfig.base",
+	"compilerOptions": {
+		"strict": true,
+		"paths": {
+			"@/*": ["./src/*"],
+			"@assets/*": ["./assets/*"]
+		}
+	},
+	"include": ["**/*.ts", "**/*.tsx", ".expo/types/**/*.ts", "expo-env.d.ts"]
+}

docs/backend-service-architecture-spec.md

@@ -0,0 +1,306 @@
+# Backend Service Architecture: Per-User Refactor
+
+## Problem Statement
+
+The current backend uses a **per-source service** pattern: each source type (Location, Weather, TFL) has its own `XxxService` class that manages a `Map<userId, SourceInstance>`. Adding a new source requires:
+
+1. A new `XxxService` class with identical boilerplate (~30-40 lines: Map, get-or-create, removeUser)
+2. Wiring it into `server.ts` constructor
+3. Passing it to `FeedEngineService`
+4. Optionally adding source-specific tRPC routes
+
+With 3 sources this is manageable. With 10+ (calendar, music, transit, news, etc.) it becomes:
+
+- **Repetitive**: Every service class repeats the same Map + get-or-create + removeUser pattern
+- **Fragmented lifecycle**: User cleanup requires calling `removeUser` on every service independently
+- **No user-level config**: No unified place to store which sources a user has enabled or their per-source settings
+- **Hard to reason about**: User state is scattered across N independent Maps
+
+### Current Flow
+
+```
+server.ts
+  ├── new LocationService()          ← owns Map<userId, LocationSource>
+  ├── new WeatherService(creds)      ← owns Map<userId, WeatherSource>
+  ├── new TflService(api)            ← owns Map<userId, TflSource>
+  └── FeedEngineService([loc, weather, tfl])
+        └── owns Map<userId, FeedEngine>
+            └── on create: asks each service for feedSourceForUser(userId)
+```
+
+4 independent Maps for 3 sources. Each user's state lives in 4 different places.
+
+## Scope
+
+**Backend only** (`apps/aris-backend`). No changes to `aris-core` or source packages (`packages/aris-source-*`). The `FeedSource` interface and source implementations remain unchanged.
+
+## Architectural Options
+
+### Option A: UserSession Object
+
+A single `UserSession` class owns everything for one user. A `UserSessionManager` is the only top-level Map.
+
+```typescript
+class UserSession {
+  readonly userId: string
+  readonly engine: FeedEngine
+  private sources: Map<string, FeedSource>
+
+  constructor(userId: string, sourceFactories: SourceFactory[]) {
+    this.engine = new FeedEngine()
+    this.sources = new Map()
+    for (const factory of sourceFactories) {
+      const source = factory.create()
+      this.sources.set(source.id, source)
+      this.engine.register(source)
+    }
+    this.engine.start()
+  }
+
+  getSource<T extends FeedSource>(id: string): T | undefined {
+    return this.sources.get(id) as T | undefined
+  }
+
+  destroy(): void {
+    this.engine.stop()
+    this.sources.clear()
+  }
+}
+
+class UserSessionManager {
+  private sessions = new Map<string, UserSession>()
+
+  getOrCreate(userId: string): UserSession { ... }
+  remove(userId: string): void { ... }  // single cleanup point
+}
+```
+
+**Source-specific operations** use typed accessors:
+
+```typescript
+const session = manager.getOrCreate(userId)
+const location = session.getSource<LocationSource>("location")
+location?.pushLocation({ lat: 51.5, lng: -0.1, ... })
+```
+
+**Pros:**
+
+- Single Map, single cleanup point
+- All user state co-located
+- Easy to add TTL/eviction at one level
+- Source factories are simple functions, no service classes needed
+
+**Cons:**
+
+- `getSource<T>("id")` requires callers to know the source ID string and cast type
+- Shared resources (e.g., TFL API client) need to be passed through factories
+
+### Option B: Source Registry with Factories
+
+Keep `FeedEngineService` but replace per-source service classes with a registry of factory functions. No `XxxService` classes at all.
+
+```typescript
+interface SourceFactory {
+  readonly sourceId: string
+  create(userId: string): FeedSource
+}
+
+// Weather factory — closure over shared credentials
+function weatherSourceFactory(creds: WeatherKitCredentials): SourceFactory {
+  return {
+    sourceId: "weather",
+    create: () => new WeatherSource({ credentials: creds }),
+  }
+}
+
+// TFL factory — closure over shared API client
+function tflSourceFactory(api: ITflApi): SourceFactory {
+  return {
+    sourceId: "tfl",
+    create: () => new TflSource({ client: api }),
+  }
+}
+
+class FeedEngineService {
+  private engines = new Map<string, FeedEngine>()
+  private userSources = new Map<string, Map<string, FeedSource>>()
+
+  constructor(private readonly factories: SourceFactory[]) {}
+
+  engineForUser(userId: string): FeedEngine { ... }
+  getSourceForUser<T extends FeedSource>(userId: string, sourceId: string): T | undefined { ... }
+  removeUser(userId: string): void { ... }  // cleans up engine + all sources
+}
+```
+
+**Pros:**
+
+- Minimal change from current structure — `FeedEngineService` evolves, services disappear
+- Factory functions are 5-10 lines each, no classes
+- Shared resources handled naturally via closures
+
+**Cons:**
+
+- `FeedEngineService` grows in responsibility (engine + source tracking + source access)
+- Still two Maps (engines + userSources), though co-located
+
+### Option C: UserSession + Typed Source Handles (Recommended)
+
+Combines Option A's co-location with type-safe source access. `UserSession` owns everything. Source-specific operations go through **source handles** — thin typed wrappers registered at setup time.
+
+```typescript
+// Source handle: typed wrapper for source-specific operations
+interface SourceHandle<T extends FeedSource = FeedSource> {
+	readonly source: T
+}
+
+class UserSession {
+	readonly engine: FeedEngine
+	private handles = new Map<string, SourceHandle>()
+
+	register<T extends FeedSource>(source: T): SourceHandle<T> {
+		this.engine.register(source)
+		const handle: SourceHandle<T> = { source }
+		this.handles.set(source.id, handle)
+		return handle
+	}
+
+	destroy(): void {
+		this.engine.stop()
+		this.handles.clear()
+	}
+}
+
+// In setup code — handles are typed at creation time
+function createSession(userId: string, deps: SessionDeps): UserSession {
+	const session = new UserSession(userId)
+
+	const locationHandle = session.register(new LocationSource())
+	const weatherHandle = session.register(new WeatherSource(deps.weatherCreds))
+	const tflHandle = session.register(new TflSource({ client: deps.tflApi }))
+
+	return session
+}
+```
+
+**Source-specific operations** use the typed handles returned at registration:
+
+```typescript
+// In the tRPC router or wherever source-specific ops happen:
+// The handle is obtained during session setup and stored where needed
+locationHandle.source.pushLocation({ ... })
+tflHandle.source.setLinesOfInterest(["northern"])
+```
+
+**Pros:**
+
+- Single Map, single cleanup
+- Type-safe source access without string-based lookups or casts
+- No boilerplate service classes
+- Handles can be extended later (e.g., add per-source config, metrics)
+- Shared resources passed directly to constructors
+
+**Cons:**
+
+- Handles need to be threaded to where they're used (tRPC routers, etc.)
+- Slightly more setup code in the factory function
+
+## Source-Specific Operations: Approaches
+
+Orthogonal to the session model, there are three ways to handle operations like `pushLocation` or `setLinesOfInterest`:
+
+### Approach 1: Direct Source Access (Recommended)
+
+Callers get a typed reference to the source and call methods directly. This is what all three options above use in different ways.
+
+```typescript
+locationSource.pushLocation(location)
+tflSource.setLinesOfInterest(lines)
+```
+
+**Why this works:** Source packages already define these methods. The backend just needs to expose the source instance to the right caller. No new abstraction needed.
+
+### Approach 2: Command Dispatch
+
+A generic `dispatch(command)` method on the session routes typed commands to sources.
+
+```typescript
+session.dispatch({ type: "location.update", payload: { lat: 51.5, ... } })
+```
+
+**Tradeoff:** Adds indirection and a command type registry. Useful if sources are dynamically loaded plugins, but over-engineered for the current case where sources are known at compile time.
+
+### Approach 3: Context-Only
+
+All input goes through `FeedEngine` context updates. Sources react to context changes.
+
+```typescript
+engine.pushContext({ [LocationKey]: location })
+// LocationSource picks this up via onContextUpdate
+```
+
+**Tradeoff:** Location already works this way (it's a context provider). But not all operations map to context — `setLinesOfInterest` is configuration, not context. Would require stretching the context concept.
+
+## User Source Configuration (DB-Persisted)
+
+Regardless of which option is chosen, user source config needs a storage model:
+
+```sql
+CREATE TABLE user_source_config (
+  user_id    TEXT NOT NULL REFERENCES users(id),
+  source_id  TEXT NOT NULL,          -- e.g., "weather", "tfl", "location"
+  enabled    BOOLEAN NOT NULL DEFAULT true,
+  config     JSONB NOT NULL DEFAULT '{}',  -- source-specific settings
+  PRIMARY KEY (user_id, source_id)
+);
+```
+
+On session creation:
+
+1. Load `user_source_config` rows for the user
+2. Only create sources where `enabled = true`
+3. Pass `config` JSON to the source factory/constructor
+
+New users get default config rows inserted on first login.
+
+## Recommendation
+
+**Option C (UserSession + Typed Source Handles)** with **Approach 1 (Direct Source Access)**.
+
+Rationale:
+
+- Eliminates all per-source service boilerplate
+- Single user lifecycle management point
+- Type-safe without string-based lookups in hot paths
+- Minimal new abstraction — `UserSession` is a thin container, not a framework
+- Handles are just typed references, not a new pattern to learn
+- Natural extension point for per-user config loading from DB
+
+## Acceptance Criteria
+
+1. **No per-source service classes**: `LocationService`, `WeatherService`, `TflService` are removed
+2. **Single user state container**: All per-user state (engine, sources) lives in one object
+3. **Single cleanup**: Removing a user requires one call, not N
+4. **Type-safe source access**: Source-specific operations don't require string-based lookups or unsafe casts at call sites
+5. **Existing tests pass**: `FeedEngineService` tests are migrated to the new structure
+6. **tRPC routes work**: Location update route works through the new architecture
+7. **DB config table**: `user_source_config` table exists; session creation reads from it
+8. **Default config**: New users get default source config on first session
+
+## Implementation Steps
+
+1. Create `user_source_config` DB table and migration
+2. Create `UserSession` class with `register()`, `destroy()`, typed handle return
+3. Create `UserSessionManager` with `getOrCreate()`, `remove()`, config loading
+4. Create `createSession()` factory that reads DB config and registers enabled sources
+5. Refactor `server.ts` to use `UserSessionManager` instead of individual services
+6. Refactor tRPC router to receive session/handles instead of individual services
+7. Delete `LocationService`, `WeatherService`, `TflService` classes
+8. Migrate existing tests to new structure
+9. Add tests for session lifecycle (create, destroy, config loading)
+
+## Open Questions
+
+- **TTL/eviction**: Should `UserSessionManager` handle idle session cleanup? (Currently deferred in backend-spec.md)
+- **Hot reload config**: If a user changes their source config, should the session be recreated or patched in-place?
+- **Shared source instances**: Some sources (e.g., TFL) share an API client. Should the factory receive shared deps, or should there be a DI container?

docs/backend-spec.md

@@ -7,12 +7,14 @@ ARIS needs a backend service that manages per-user FeedEngine instances and deli
 ## Requirements
 
 ### Authentication
+
 - Email/password authentication using BetterAuth
 - PostgreSQL for session and user storage
 - Session tokens validated via `Authorization: Bearer <token>` header
 - Auth endpoints exposed via BetterAuth's built-in routes
 
 ### FeedEngine Management
+
 - Each authenticated user gets their own FeedEngine instance
 - Instances are cached in memory with a 30-minute TTL
 - TTL resets on any activity (WebSocket message, location update)
@@ -20,6 +22,7 @@ ARIS needs a backend service that manages per-user FeedEngine instances and deli
 - Source configuration is hardcoded initially (customization deferred)
 
 ### WebSocket Connection
+
 - Single endpoint: `GET /ws` (upgrades to WebSocket)
 - Authentication via `Authorization: Bearer <token>` header on upgrade request
 - Rejected before upgrade if token is invalid
@@ -28,20 +31,24 @@ ARIS needs a backend service that manages per-user FeedEngine instances and deli
 - On connect: immediately send current feed state
 
 ### JSON-RPC Protocol
+
 All WebSocket communication uses JSON-RPC 2.0.
 
 **Client → Server (Requests):**
+
 ```json
 { "jsonrpc": "2.0", "method": "location.update", "params": { "lat": 51.5, "lng": -0.1, "accuracy": 10, "timestamp": "2025-01-01T12:00:00Z" }, "id": 1 }
 { "jsonrpc": "2.0", "method": "feed.refresh", "params": {}, "id": 2 }
 ```
 
 **Server → Client (Responses):**
+
 ```json
 { "jsonrpc": "2.0", "result": { "ok": true }, "id": 1 }
 ```
 
 **Server → Client (Notifications - no id):**
+
 ```json
 { "jsonrpc": "2.0", "method": "feed.update", "params": { "items": [...], "errors": [...] } }
 ```
@@ -49,18 +56,19 @@ All WebSocket communication uses JSON-RPC 2.0.
 ### JSON-RPC Methods
 
 | Method            | Params                              | Description                                 |
-|--------|--------|-------------|
+| ----------------- | ----------------------------------- | ------------------------------------------- |
 | `location.update` | `{ lat, lng, accuracy, timestamp }` | Push location update, triggers feed refresh |
 | `feed.refresh`    | `{}`                                | Force manual feed refresh                   |
 
 ### Server Notifications
 
 | Method        | Params                       | Description            |
-|--------|--------|-------------|
+| ------------- | ---------------------------- | ---------------------- |
 | `feed.update` | `{ context, items, errors }` | Feed state changed     |
 | `error`       | `{ code, message, data? }`   | Source or system error |
 
 ### Error Handling
+
 - Source failures during refresh are reported via `error` notification
 - Format: `{ "jsonrpc": "2.0", "method": "error", "params": { "code": -32000, "message": "...", "data": { "sourceId": "weather" } } }`
 
@@ -96,16 +104,19 @@ All WebSocket communication uses JSON-RPC 2.0.
 ## Implementation Approach
 
 ### Phase 1: Project Setup
+
 1. Create `apps/aris-backend` with Hono
 2. Configure TypeScript, add dependencies (hono, better-auth, postgres driver)
 3. Set up database connection and BetterAuth
 
 ### Phase 2: Authentication
+
 4. Configure BetterAuth with email/password provider
 5. Mount BetterAuth routes at `/api/auth/*`
 6. Create session validation helper for extracting user from token
 
 ### Phase 3: FeedEngine Manager
+
 7. Create `FeedEngineManager` class:
    - `getOrCreate(userId): FeedEngine` - returns cached or creates new
    - `touch(userId)` - resets TTL
@@ -114,22 +125,26 @@ All WebSocket communication uses JSON-RPC 2.0.
 8. Factory function to create FeedEngine with default sources
 
 ### Phase 4: WebSocket Handler
+
 9. Create WebSocket upgrade endpoint at `/ws`
 10. Validate `Authorization` header before upgrade
 11. On connect: register connection, send initial feed state
 12. On disconnect: unregister connection
 
 ### Phase 5: JSON-RPC Handler
+
 13. Create JSON-RPC message parser and dispatcher
 14. Implement `location.update` method
 15. Implement `feed.refresh` method
 16. Wire FeedEngine subscription to broadcast `feed.update` to all user connections
 
 ### Phase 6: Connection Manager
+
 17. Create `ConnectionManager` to track WebSocket connections per user
 18. Broadcast helper to send to all connections for a user
 
 ### Phase 7: Integration & Testing
+
 19. Integration test: auth → connect → location update → receive feed
 20. Test multiple connections receive same updates
 21. Test TTL cleanup

docs/feed-source-actions-spec.md

@@ -0,0 +1,269 @@
+# FeedSource Actions
+
+## Problem Statement
+
+`FeedSource` is read-only. Sources can provide context and feed items but can't expose write operations (play, RSVP, dismiss). This blocks interactive sources like Spotify, calendar, and tasks.
+
+## Scope
+
+**`aris-core` only.** Add action support to `FeedSource` and `FeedItem`. No changes to existing fields or methods — purely additive.
+
+## Design
+
+### Why Not MCP
+
+MCP was considered. It doesn't fit because:
+
+- MCP resources don't accept input context (FeedSource needs accumulated context as input)
+- MCP has no structured feed items (priority, timestamp, type)
+- MCP's isolation model conflicts with ARIS's dependency graph
+- Adding these as MCP extensions would mean the extensions are the entire protocol
+
+The interface is designed to be **protocol-compatible** — a future `RemoteFeedSource` adapter can map each field/method to a JSON-RPC operation without changing the interface:
+
+| FeedSource field/method | Future protocol operation |
+| ----------------------- | ------------------------- |
+| `id`, `dependencies`    | `source/describe`         |
+| `listActions()`         | `source/listActions`      |
+| `fetchContext()`        | `source/fetchContext`     |
+| `fetchItems()`          | `source/fetchItems`       |
+| `executeAction()`       | `source/executeAction`    |
+| `onContextUpdate()`     | `source/contextUpdated`   |
+| `onItemsUpdate()`       | `source/itemsUpdated`     |
+
+No interface changes needed when the transport layer is built.
+
+### Source ID & Action ID Convention
+
+Source IDs use reverse domain notation. Built-in sources use `aris.<name>`. Third parties use their own domain.
+
+Action IDs are descriptive verb-noun pairs in kebab-case, scoped to their source. The globally unique form is `<sourceId>/<actionId>`.
+
+| Source ID       | Action IDs                                                     |
+| --------------- | -------------------------------------------------------------- |
+| `aris.location` | `update-location` (migrated from `pushLocation()`)             |
+| `aris.tfl`      | `set-lines-of-interest` (migrated from `setLinesOfInterest()`) |
+| `aris.weather`  | _(none)_                                                       |
+| `com.spotify`   | `play-track`, `pause-playback`, `skip-track`, `like-track`     |
+| `aris.calendar` | `rsvp`, `create-event`                                         |
+| `com.todoist`   | `complete-task`, `snooze-task`                                 |
+
+This means existing source packages need their `id` updated (e.g., `"location"` → `"aris.location"`).
+
+### New Types
+
+```typescript
+/** Describes an action a source can perform. */
+interface ActionDefinition<TInput = unknown> {
+	/** Descriptive action name in kebab-case (e.g., "update-location", "play-track") */
+	readonly id: string
+	/** Human-readable label for UI (e.g., "Play", "RSVP Yes") */
+	readonly label: string
+	/** Optional longer description */
+	readonly description?: string
+	/** Schema for input validation. Accepts any Standard Schema compatible validator (arktype, zod, valibot, etc.). Omit if no params. */
+	readonly input?: StandardSchemaV1<TInput>
+}
+```
+
+`StandardSchemaV1` is the [Standard Schema](https://github.com/standard-schema/standard-schema) interface implemented by arktype, zod, and valibot. This means sources can use any validator:
+
+```typescript
+import { type } from "arktype"
+import { z } from "zod"
+
+// With arktype
+{ id: "play-track", label: "Play", input: type({ trackId: "string" }) }
+
+// With zod
+{ id: "play-track", label: "Play", input: z.object({ trackId: z.string() }) }
+
+// Without validation (e.g., remote sources using raw JSON Schema)
+{ id: "play-track", label: "Play" }
+
+/** Result of executing an action. */
+interface ActionResult {
+  ok: boolean
+  data?: Record<string, unknown>
+  error?: string
+}
+
+/** Reference to an action on a specific feed item. */
+interface ItemAction {
+  /** Action ID (matches ActionDefinition.id on the source) */
+  actionId: string
+  /** Per-item label override (e.g., "RSVP to standup") */
+  label?: string
+  /** Pre-filled params for this item (e.g., { eventId: "abc" }) */
+  params?: Record<string, unknown>
+}
+```
+
+### Changes to FeedSource
+
+Two optional fields added. Nothing else changes.
+
+```typescript
+interface FeedSource<TItem extends FeedItem = FeedItem> {
+  readonly id: string                              // unchanged
+  readonly dependencies?: readonly string[]        // unchanged
+  fetchContext(...): ...                            // unchanged
+  onContextUpdate?(...): ...                       // unchanged
+  fetchItems?(...): ...                            // unchanged
+  onItemsUpdate?(...): ...                         // unchanged
+
+  /** List actions this source supports. Empty record if none. Maps to: source/listActions */
+  listActions(): Promise<Record<string, ActionDefinition>>
+
+  /** Execute an action by ID. No-op returning { ok: false } if source has no actions. */
+  executeAction(
+    actionId: string,
+    params: Record<string, unknown>,
+  ): Promise<ActionResult>
+}
+```
+
+### Changes to FeedItem
+
+One optional field added.
+
+```typescript
+interface FeedItem<
+	TType extends string = string,
+	TData extends Record<string, unknown> = Record<string, unknown>,
+> {
+	id: string // unchanged
+	type: TType // unchanged
+	priority: number // unchanged
+	timestamp: Date // unchanged
+	data: TData // unchanged
+
+	/** Actions the user can take on this item. */
+	actions?: readonly ItemAction[]
+}
+```
+
+### Changes to FeedEngine
+
+Two new methods. Existing methods unchanged.
+
+```typescript
+class FeedEngine {
+	// All existing methods unchanged...
+
+	/** Route an action call to the correct source. */
+	async executeAction(
+		sourceId: string,
+		actionId: string,
+		params: Record<string, unknown>,
+	): Promise<ActionResult>
+
+	/** List all actions across all registered sources. */
+	listActions(): { sourceId: string; actions: readonly ActionDefinition[] }[]
+}
+```
+
+### Example: Spotify Source
+
+```typescript
+class SpotifySource implements FeedSource<SpotifyFeedItem> {
+	readonly id = "com.spotify"
+
+	async listActions() {
+		return {
+			"play-track": { id: "play-track", label: "Play", input: type({ trackId: "string" }) },
+			"pause-playback": { id: "pause-playback", label: "Pause" },
+			"skip-track": { id: "skip-track", label: "Skip" },
+			"like-track": { id: "like-track", label: "Like", input: type({ trackId: "string" }) },
+		}
+	}
+
+	async executeAction(actionId: string, params: Record<string, unknown>): Promise<ActionResult> {
+		switch (actionId) {
+			case "play-track":
+				await this.client.play(params.trackId as string)
+				return { ok: true }
+			case "pause-playback":
+				await this.client.pause()
+				return { ok: true }
+			case "skip-track":
+				await this.client.skip()
+				return { ok: true }
+			case "like-track":
+				await this.client.like(params.trackId as string)
+				return { ok: true }
+			default:
+				return { ok: false, error: `Unknown action: ${actionId}` }
+		}
+	}
+
+	async fetchContext(): Promise<null> {
+		return null
+	}
+
+	// Note: for a source with no actions, it would be:
+	// async listActions() { return {} }
+	// async executeAction(): Promise<ActionResult> {
+	//   return { ok: false, error: "No actions supported" }
+	// }
+
+	async fetchItems(context: Context): Promise<SpotifyFeedItem[]> {
+		const track = await this.client.getCurrentTrack()
+		if (!track) return []
+		return [
+			{
+				id: `spotify-${track.id}`,
+				type: "spotify-now-playing",
+				priority: 0.4,
+				timestamp: context.time,
+				data: { trackName: track.name, artist: track.artist },
+				actions: [
+					{ actionId: "pause-playback" },
+					{ actionId: "skip-track" },
+					{ actionId: "like-track", params: { trackId: track.id } },
+				],
+			},
+		]
+	}
+}
+```
+
+## Acceptance Criteria
+
+1. `ActionDefinition` type exists with `id`, `label`, `description?`, `inputSchema?`
+2. `ActionResult` type exists with `ok`, `data?`, `error?`
+3. `ItemAction` type exists with `actionId`, `label?`, `params?`
+4. `FeedSource.listActions()` is a required method returning `Record<string, ActionDefinition>` (empty record if no actions)
+5. `FeedSource.executeAction()` is a required method (no-op for sources without actions)
+6. `FeedItem.actions` is an optional readonly array of `ItemAction`
+7. `FeedEngine.executeAction()` routes to correct source, returns `ActionResult`
+8. `FeedEngine.listActions()` aggregates actions from all sources
+9. Existing tests pass unchanged (all changes are additive)
+10. New tests: action execution, unknown action ID, unknown source ID, source without actions, `listActions()` aggregation
+
+## Implementation Steps
+
+1. Create `action.ts` in `aris-core/src` with `ActionDefinition`, `ActionResult`, `ItemAction`
+2. Add optional `actions` and `executeAction` to `FeedSource` interface in `feed-source.ts`
+3. Add optional `actions` field to `FeedItem` interface in `feed.ts`
+4. Add `executeAction()` and `listActions()` to `FeedEngine` in `feed-engine.ts`
+5. Export new types from `aris-core/index.ts`
+6. Add tests for `FeedEngine.executeAction()` routing
+7. Add tests for `FeedEngine.listActions()` aggregation
+8. Add tests for error cases (unknown action, unknown source, source without actions)
+9. Update source IDs to reverse-domain format (`"location"` → `"aris.location"`, etc.) across all source packages
+10. Migrate `LocationSource.pushLocation()` → action `update-location` on `aris.location`
+11. Migrate `TflSource.setLinesOfInterest()` → action `set-lines-of-interest` on `aris.tfl`
+12. Add `async listActions() { return {} }` and no-op `executeAction()` to sources without actions (WeatherSource, GoogleCalendarSource, AppleCalendarSource)
+13. Update any tests or code referencing old source IDs
+14. Run all tests to confirm nothing breaks
+
+## What This Defers
+
+- Transport layer (JSON-RPC over HTTP/WebSocket) — built when remote sources are needed
+- `RemoteFeedSource` adapter — mechanical once transport exists
+- MCP adapter — wraps MCP servers as FeedSource
+- Runtime schema validation of action params
+- Action permissions / confirmation UI
+- Source discovery / registry API
+- Backend service consolidation (separate spec, depends on this one)