> For AI agents: the complete documentation index is available at /llms.txt, the full documentation bundle is available at /llms-full.txt.

# lambda/\*.ts

After enabling BFF, the files under the `lambda/` directory will be registered as BFF routes according to conventions.

:::note
The files can be written in `js` or `ts` languages, but they must use `esm` syntax to export functions.
:::

For detailed information, refer to [BFF API Routes](/guides/advanced-features/bff/function.md#api-routes).