Bindings

Bindings connect your deployed functions to platform resources like key-value stores, databases, object storage, and message queues. Attach bindings at deploy time and access them through fold in your function code via @fold-run/runtime.

Binding types

Type	Description	fold accessor
key-value	Key-value storage for fast reads	fold.kv
database	SQL database (per-organization)	fold.db
object-storage	Object storage for files and blobs	fold.storage
queue	Message queue for async processing	fold.queue

Configuring bindings

Bindings are set up by your team admin in the dashboard at app.fold.run/console/bindings. Each binding has a logical name (like user-cache) and a type (key-value, database, object-storage, queue).

If you need a new binding, ask your team admin to create one from the dashboard.

Listing bindings

curl "https://api.fold.run/bindings" \
  -H "Authorization: Bearer YOUR_TOKEN"

Response:

{
  "bindings": [
    {
      "id": "bind_abc123def456",
      "tenant_id": "my-tenant",
      "name": "user-cache",
      "type": "key-value",
      "resource_id": "kv-namespace-id"
    }
  ]
}

Using bindings in deploys

Attach bindings when deploying by including them in the intent.bindings array:

curl -X POST https://api.fold.run/deploy \
  -H "Authorization: Bearer YOUR_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "my-api",
    "code": "...",
    "intent": {
      "bindings": ["key-value:user-cache"]
    }
  }'

The binding format is TYPE:name — the type and the logical name you gave it when creating the binding.

Or with the CLI via fold.json:

{
  "name": "my-api",
  "entrypoint": "function.ts",
  "intent": {
    "bindings": ["key-value:user-cache"]
  }
}

Accessing bindings in your code

Use @fold-run/runtime to access bindings through the typed fold object — no raw binding names needed:

import { defineHandler, type FoldContext } from '@fold-run/runtime';

export default defineHandler(async (fold: FoldContext) => {
  // KV — key-value store
  const cached = await fold.kv.get('session:abc');
  await fold.kv.put('session:abc', 'value');

  // DB — SQL database
  const rows = await fold.db
    .prepare('SELECT * FROM orders WHERE user_id = ?')
    .bind('user-123')
    .all();

  // Storage — object storage
  const file = await fold.storage.get('report.pdf');
  await fold.storage.put('output.json', JSON.stringify({ ok: true }));

  // Queue — async message passing
  await fold.queue.send({ type: 'email', to: 'user@example.com' });

  return fold.json({ ok: true });
});

Each fold accessor maps to the binding attached to your function via fold.json or the dashboard (Functions → Bindings). The runtime resolves the correct resource at deploy time — you never reference binding names in code.

For the full fold API reference, see the `@fold-run/runtime` README.

Allowed bindings

Each organization has an allowlist of permitted binding types. If you try to deploy with a binding type that isn't allowed for your organization, the deploy will fail with BINDING_NOT_FOUND.

Contact your team admin or configure additional bindings in the dashboard.