Only Stateless APIs
Lumen 5.2 represents a shift on slimming Lumen to focus solely on serving stateless, JSON APIs. As such, sessions and views are no longer included with the framework. If you need access to these features, you should use the full Laravel framework. Upgrading your Lumen application to the full Laravel framework mainly involves copying your routes and classes over into a fresh installation of Laravel. Since Laravel and Lumen share many of the same components, your classes should not require any modification.
https://lumen.laravel.com/docs/5.2/releases#5.2.0
Так что можно использовать либо старые версии, либо прикручивать самому.
Torch вам в помощь.
