Is it possible to use immutable if the entity has a field that uses the @derivedFrom directive?

[PaulRBerg]

Given an entity defined like so:

type Batch @entity {
  id: String!
  hash: Bytes!
  timestamp: BigInt!
  batcher: Batcher
  size: BigInt!
  streams: [Stream!]! @derivedFrom(field: "batch")
}

Is it possible to mark it as immutable if I only do batch.save() once but I continue creating streams that will make the streams field change over time?

The Stream entity is not immutable, of course:

type Stream @entity {
  batch: Batch!
}

[PaulRBerg]

The answer is yes — it is possible to mark an entity as immutable: true when it contains a field uses the @derivedFrom directive: