You're seeing just the function encrypt, go back to Erebus module for more information.
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encrypt(struct, handle, version, opts)

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This function should be called when you want to encrypt your struct. It takes:

  • struct which implements Erebus.Encryption protocol
  • handle for key
  • version of key
  • options - providing backend and options for that backend

One very meaningful option is :force_reencrypt flag, which can be used for re-encrypting all of the fields even when nothing was changed.