API Routes

TMA.sh lets you add server-side logic to your Mini App by creating a Hono app in server/api/index.ts. At build time, TMA.sh detects this file, bundles it with esbuild, and deploys it to Cloudflare Workers for Platforms. Your API becomes available at {project}--api.tma.sh/api/*.

Quick start

Create a server/api/index.ts file in the root of your project:

import { Hono } from 'hono';

const app = new Hono();

app.get('/api/health', (c) => c.json({ status: 'ok' }));

app.post('/api/items', async (c) => {
  const body = await c.req.json();
  return c.json({ created: true, item: body });
});

export default app;

Deploy as usual with tma deploy. TMA.sh will detect the API entry point and bundle it automatically alongside your static assets.

Your static SPA is served at {project}.tma.sh and your API at {project}--api.tma.sh/api/*. Same-origin /api/* requests on {project}.tma.sh are also proxied to the API worker, so you can use relative paths like /api/health from your client-side code.

Available bindings

API routes run on Cloudflare Workers and have access to the following bindings:

• KV — a per-project KV namespace, provisioned automatically
• Environment variables — secrets and configuration set via the dashboard or tma env

Use TypeScript generics to get typed access to bindings:

import { Hono } from 'hono';

type Env = {
  Bindings: {
    KV: KVNamespace;
    MY_SECRET: string;
    DATABASE_URL: string;
  };
};

const app = new Hono<Env>();

app.get('/api/config', async (c) => {
  const cached = await c.env.KV.get('app-config');
  if (cached) {
    return c.json(JSON.parse(cached));
  }

  const config = { version: '1.0.0' };
  await c.env.KV.put('app-config', JSON.stringify(config), {
    expirationTtl: 3600,
  });

  return c.json(config);
});

export default app;

External databases

Per-project D1 is not available in the current release. For relational data, connect to an external database from your API routes:

• Supabase — use the Supabase client with your project’s JWT (see Authentication)
• Turso — use @libsql/client with a database URL and auth token stored as environment variables
• PlanetScale — use @planetscale/database with a connection string

import { Hono } from 'hono';
import { createClient } from '@libsql/client';

type Env = {
  Bindings: {
    TURSO_URL: string;
    TURSO_AUTH_TOKEN: string;
  };
};

const app = new Hono<Env>();

app.get('/api/users', async (c) => {
  const db = createClient({
    url: c.env.TURSO_URL,
    authToken: c.env.TURSO_AUTH_TOKEN,
  });

  const result = await db.execute('SELECT * FROM users LIMIT 50');
  return c.json(result.rows);
});

export default app;

Middleware

Hono’s middleware works as expected. Common patterns include CORS, logging, and authentication:

import { Hono } from 'hono';
import { cors } from 'hono/cors';

const app = new Hono();

app.use('/api/*', cors({
  origin: ['https://myapp.tma.sh'],
  allowMethods: ['GET', 'POST', 'PUT', 'DELETE'],
}));

app.get('/api/data', (c) => c.json({ hello: 'world' }));

export default app;

Limits

Resource	Limit
Bundle size	10 MB
Request body	100 MB
Execution time	30 seconds
Subrequests	50 per request

Route organization

For larger APIs, use Hono’s route grouping:

import { Hono } from 'hono';
import { users } from './routes/users';
import { items } from './routes/items';

const app = new Hono();

app.route('/api/users', users);
app.route('/api/items', items);

export default app;

All routes imported from subdirectories will be included in the esbuild bundle automatically. Only server/api/index.ts is used as the entry point.