feat: add D1 runtime database binding

src/lib/server/auth.ts

@@ -3,13 +3,24 @@ import { drizzleAdapter } from 'better-auth/adapters/drizzle';
 import { admin } from 'better-auth/plugins';
 import { sveltekitCookies } from 'better-auth/svelte-kit';
 import { env } from '$env/dynamic/private';
+import { building } from '$app/environment';
 import { getRequestEvent } from '$app/server';
 import { db } from '$lib/server/db';
+import * as schema from '$lib/server/db/schema';
+
+const buildTimeOrigin = 'http://localhost:5173';
+const buildTimeSecret = 'clearity-build-time-placeholder-secret';
+
+const origin = env.ORIGIN ?? (building ? buildTimeOrigin : undefined);
+const secret = env.BETTER_AUTH_SECRET ?? (building ? buildTimeSecret : undefined);
+
+if (!origin) throw new Error('ORIGIN is not set');
+if (!secret) throw new Error('BETTER_AUTH_SECRET is not set');
 
 export const auth = betterAuth({
-	baseURL: env.ORIGIN,
+	baseURL: origin,
-	secret: env.BETTER_AUTH_SECRET,
+	secret,
-	database: drizzleAdapter(db, { provider: 'sqlite' }),
+	database: drizzleAdapter(db, { provider: 'sqlite', schema }),
 	emailAndPassword: {
 		enabled: true,
 		disableSignUp: true

src/lib/server/db/index.ts

@@ -1,10 +1,74 @@
-import { drizzle } from 'drizzle-orm/libsql';
-import { createClient } from '@libsql/client';
-import * as schema from './schema';
 import { env } from '$env/dynamic/private';
+import { getRequestEvent } from '$app/server';
+import { createClient, type Client } from '@libsql/client';
+import { drizzle as drizzleD1, type DrizzleD1Database } from 'drizzle-orm/d1';
+import { drizzle as drizzleLibSQL, type LibSQLDatabase } from 'drizzle-orm/libsql';
+import * as schema from './schema';
 
-if (!env.DATABASE_URL) throw new Error('DATABASE_URL is not set');
+type Schema = typeof schema;
+type LocalDatabase = LibSQLDatabase<Schema> & { $client: Client };
+type D1DatabaseClient = DrizzleD1Database<Schema> & { $client: D1Database };
 
-const client = createClient({ url: env.DATABASE_URL });
+export type Database = LocalDatabase;
+export type RuntimeDatabase = LocalDatabase | D1DatabaseClient;
 
-export const db = drizzle(client, { schema });
+let localDb: LocalDatabase | undefined;
+const d1Databases = new WeakMap<D1Database, D1DatabaseClient>();
+
+function getD1Binding() {
+	try {
+		return getRequestEvent().platform?.env.DB;
+	} catch {
+		return undefined;
+	}
+}
+
+function getLocalDb() {
+	if (localDb) return localDb;
+	if (!env.DATABASE_URL)
+		throw new Error('DATABASE_URL is not set and no Cloudflare D1 DB binding is available');
+
+	const client = createClient({ url: env.DATABASE_URL });
+	localDb = drizzleLibSQL(client, { schema });
+
+	return localDb;
+}
+
+function getD1Db(binding: D1Database) {
+	const cached = d1Databases.get(binding);
+	if (cached) return cached;
+
+	const database = drizzleD1(binding, { schema });
+	d1Databases.set(binding, database);
+
+	return database;
+}
+
+export function getDb(): RuntimeDatabase {
+	if (env.DATABASE_URL) return getLocalDb();
+
+	const d1Binding = getD1Binding();
+	if (d1Binding) return getD1Db(d1Binding);
+
+	return getLocalDb();
+}
+
+export const db = new Proxy({} as Database, {
+	get(_target, property) {
+		const database = getDb();
+		const value = Reflect.get(database, property);
+		return typeof value === 'function' ? value.bind(database) : value;
+	},
+	getOwnPropertyDescriptor(_target, property) {
+		return Reflect.getOwnPropertyDescriptor(getDb(), property);
+	},
+	getPrototypeOf() {
+		return Reflect.getPrototypeOf(getDb());
+	},
+	has(_target, property) {
+		return property in getDb();
+	},
+	ownKeys() {
+		return Reflect.ownKeys(getDb());
+	}
+});

worker-configuration.d.ts

@@ -1,11 +1,9 @@
 /* eslint-disable */
-// Generated by Wrangler by running `wrangler types` (hash: 61c64c9cd1c2465ff3a92bc5ac82d57d)
+// Generated by Wrangler by running `wrangler types` (hash: f6e835394237f01fba038726e2d4f9ae)
 // Runtime types generated with workerd@1.20260521.1 2026-05-23 nodejs_als
 interface __BaseEnv_Env {
+	DB: D1Database;
 	ASSETS: Fetcher;
-	DATABASE_URL: string;
-	ORIGIN: string;
-	BETTER_AUTH_SECRET: string;
 }
 declare namespace Cloudflare {
 	interface Env extends __BaseEnv_Env {}

wrangler.jsonc

@@ -8,6 +8,14 @@
 		"binding": "ASSETS",
 		"directory": ".svelte-kit/cloudflare"
 	},
+	"d1_databases": [
+		{
+			"binding": "DB",
+			"database_name": "clearity-production",
+			"database_id": "<replace-with-d1-database-id>",
+			"migrations_dir": "drizzle"
+		}
+	],
 	"workers_dev": true,
 	"preview_urls": true
 }