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Use cases → Email operations

Standardise email signatures across the company

Set and enforce consistent Gmail signatures for all users by updating profiles via a delegated service account.

Who it is forIT administrators enforcing brand and compliance standards in employee email signatures.
APIsGmail API, Admin SDK
Typical scopesgmail.settings.basic, admin.directory.user

The problem

Manually maintained signatures drift over time, breaking legal and branding requirements. Relying on users to update their own signatures leads to inconsistency and outdated details.

How it works

  1. Fetch the user list from the Admin SDK.
  2. For each user, impersonate them using a delegated service account.
  3. Use the Gmail API to update the 'sendAs' signature field for their primary address.
  4. Log each update and alert on any errors.
  5. Optionally, re-run periodically or on user creation.

What changes

All user signatures match the latest standard and updates propagate rapidly, eliminating manual drift and outdated content.

The trap in this one. The Gmail API will silently skip signature updates if the user has never opened Gmail (i.e., if the mailbox is uninitialised), leading to a mismatch between directory population and actual signature coverage. This only surfaces when a new starter’s first outbound mail carries no signature, despite logs claiming success.

Questions people ask

Can I enforce signatures for all aliases?

You must update the signature for each 'sendAs' address individually; the API does not cascade changes to aliases automatically.

How quickly do signature changes take effect?

Updates are usually instant for webmail. Some mobile clients cache signatures and may require a restart or refresh.

Want this built?

This is a pattern we run in production. We will set up the delegation and build this on top of it — $500 per hour, most of it working the same day.

Talk to us Or read the setup guide

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