diff --git a/packages/api/DittoApp.test.ts b/packages/api/DittoApp.test.ts
new file mode 100644
index 00000000..b6525eed
--- /dev/null
+++ b/packages/api/DittoApp.test.ts
@@ -0,0 +1,16 @@
+import { Hono } from '@hono/hono';
+
+import { DittoApp } from './DittoApp.ts';
+import { DittoRoute } from './DittoRoute.ts';
+
+Deno.test('DittoApp', () => {
+  const app = new DittoApp();
+
+  const hono = new Hono();
+  const route = new DittoRoute();
+
+  app.route('/', route);
+
+  // @ts-expect-error Passing a non-DittoRoute to route.
+  app.route('/', hono);
+});
diff --git a/packages/api/DittoApp.ts b/packages/api/DittoApp.ts
new file mode 100644
index 00000000..3e154e17
--- /dev/null
+++ b/packages/api/DittoApp.ts
@@ -0,0 +1,8 @@
+import { Hono } from '@hono/hono';
+
+import type { DittoEnv } from './DittoEnv.ts';
+
+export class DittoApp extends Hono<DittoEnv> {
+  // @ts-ignore Require a DittoRoute for type safety.
+  declare route: (path: string, app: Hono<DittoEnv>) => Hono<DittoEnv>;
+}
diff --git a/packages/api/DittoEnv.ts b/packages/api/DittoEnv.ts
new file mode 100644
index 00000000..d82ed911
--- /dev/null
+++ b/packages/api/DittoEnv.ts
@@ -0,0 +1,17 @@
+import type { DittoConf } from '@ditto/conf';
+import type { DittoDatabase } from '@ditto/db';
+import type { Env } from '@hono/hono';
+import type { NRelay } from '@nostrify/nostrify';
+
+export interface DittoEnv extends Env {
+  Variables: {
+    /** Ditto site configuration. */
+    conf: DittoConf;
+    /** Main database. */
+    store: NRelay;
+    /** Database object. */
+    db: DittoDatabase;
+    /** Abort signal for the request. */
+    signal: AbortSignal;
+  };
+}
diff --git a/packages/api/DittoRoute.test.ts b/packages/api/DittoRoute.test.ts
new file mode 100644
index 00000000..737019c4
--- /dev/null
+++ b/packages/api/DittoRoute.test.ts
@@ -0,0 +1,12 @@
+import { assertEquals } from '@std/assert';
+
+import { DittoRoute } from './DittoRoute.ts';
+
+Deno.test('DittoRoute', async () => {
+  const route = new DittoRoute();
+  const response = await route.request('/');
+  const body = await response.json();
+
+  assertEquals(response.status, 500);
+  assertEquals(body, { error: 'Missing required variable: db' });
+});
diff --git a/packages/api/DittoRoute.ts b/packages/api/DittoRoute.ts
index cebbc06a..d1b06a86 100644
--- a/packages/api/DittoRoute.ts
+++ b/packages/api/DittoRoute.ts
@@ -1,52 +1,59 @@
-import { type Env, Hono } from '@hono/hono';
+import { type Context, type ErrorHandler, Hono } from '@hono/hono';
+import { HTTPException } from '@hono/hono/http-exception';
 
-import type { DittoConf } from '@ditto/conf';
-import type { DittoDatabase, DittoTables } from '@ditto/db';
 import type { HonoOptions } from '@hono/hono/hono-base';
-import type { NostrSigner, NPool, NRelay, NStore, NUploader } from '@nostrify/nostrify';
-import type { Kysely } from 'kysely';
-
-interface DittoEnv extends Env {
-  Variables: {
-    conf: DittoConf;
-    user?: {
-      /** Signer to get the logged-in user's pubkey, relays, and to sign events, or `undefined` if the user isn't logged in. */
-      signer: NostrSigner;
-      /** Storage for the user, might filter out unwanted content. */
-      store: NStore;
-    };
-    /** Uploader for the user to upload files. */
-    uploader?: NUploader;
-    /** Kysely instance for the database. */
-    kysely: Kysely<DittoTables>;
-    /** Main database. */
-    store: NRelay;
-    /** Internal Nostr relay for realtime subscriptions. */
-    pubsub: NRelay;
-    /** Nostr relay pool. */
-    pool: NPool<NRelay>;
-    /** Database object. */
-    db: DittoDatabase;
-    /** Normalized pagination params. */
-    pagination: { since?: number; until?: number; limit: number };
-    /** Normalized list pagination params. */
-    listPagination: { offset: number; limit: number };
-    /** Translation service. */
-    translator?: DittoTranslator;
-    signal: AbortSignal;
-    pipeline: Pick<NStore, 'event'>;
-  };
-}
+import type { DittoEnv } from './DittoEnv.ts';
 
+/**
+ * Ditto base route class.
+ * Ensures that required variables are set for type safety.
+ */
 export class DittoRoute extends Hono<DittoEnv> {
   constructor(opts: HonoOptions<DittoEnv> = {}) {
     super(opts);
-    this.init();
-  }
 
-  init(): void {
     this.use((c, next) => {
+      this.setSignal(c);
+      this.assertVars(c.var);
       return next();
     });
+
+    this.onError(this._errorHandler);
   }
+
+  private setSignal(c: Context<DittoEnv>): void {
+    if (!c.var.signal) {
+      c.set('signal', c.req.raw.signal);
+    }
+  }
+
+  private assertVars(vars: Partial<DittoEnv['Variables']>): DittoEnv['Variables'] {
+    if (!vars.db) this.throwMissingVar('db');
+    if (!vars.conf) this.throwMissingVar('conf');
+    if (!vars.store) this.throwMissingVar('store');
+    if (!vars.signal) this.throwMissingVar('signal');
+
+    return {
+      db: vars.db,
+      conf: vars.conf,
+      store: vars.store,
+      signal: vars.signal,
+    };
+  }
+
+  private throwMissingVar(name: string): never {
+    throw new HTTPException(500, { message: `Missing required variable: ${name}` });
+  }
+
+  private _errorHandler: ErrorHandler = (error, c) => {
+    if (error instanceof HTTPException) {
+      if (error.res) {
+        return error.res;
+      } else {
+        return c.json({ error: error.message }, error.status);
+      }
+    }
+
+    return c.json({ error: 'Something went wrong' }, 500);
+  };
 }
diff --git a/packages/api/deno.json b/packages/api/deno.json
index a8bbb3f5..f9befe4b 100644
--- a/packages/api/deno.json
+++ b/packages/api/deno.json
@@ -2,6 +2,7 @@
   "name": "@ditto/api",
   "version": "1.1.0",
   "exports": {
+    ".": "./mod.ts",
     "./middleware": "./middleware/mod.ts"
   }
 }
diff --git a/packages/api/mod.ts b/packages/api/mod.ts
index ee8dc644..8e9d1d46 100644
--- a/packages/api/mod.ts
+++ b/packages/api/mod.ts
@@ -1 +1,4 @@
+export { DittoApp } from './DittoApp.ts';
 export { DittoRoute } from './DittoRoute.ts';
+
+export type { DittoEnv } from './DittoEnv.ts';