Step 3: Transform the email address

Extract the domain while the source value is available, remove the address, then add the derived fields.

Email mapping

- mapping: |
    root = this.without("email")

    root.email_hash = this.email.hash(
      "hmac_sha256",
      env("EMAIL_SALT")
    ).encode("hex")
    root.email_domain = this.email.split("@").index(1)

Validate missing and malformed addresses before adapting this fragment. A domain or stable hash may still be sensitive in a particular dataset.

Next: replace the user name.