A multitenant deployment includes a computing cluster that executes multiple containerized instances of a software application. Each containerized instance is associated with one or more datastores that can be assigned to different tenants. A registry store maintains a mapping between tenants and datastores, thereby allowing a registry manager to properly route tenant requests to the correct datastores. A capacity manager tracks tenant usage of datastores in the registry store and then scales computing resources for each tenant in proportion to usage. The capacity manager also migrates tenant resources in response to catastrophic failures or upgrades. In this fashion, the multitenant deployment can adapt a single-tenant software application for multi-tenancy in a manner that is both transparent and secure for the tenant.