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Use cases → Admin and governance

Notify all users during a security incident with bulk email

Use a delegated service account to rapidly notify all users when a security incident requires urgent action or awareness.

Who it is forIT and security teams responsible for incident response communication.
APIsGmail API, Admin SDK
Typical scopesgmail.send, admin.directory.user.readonly

The problem

When an incident hits, every minute counts. Manual mailing lists are always slightly out of date, and mass notifications with personalisation or auditability cannot be trusted to third-party tools or group aliases.

How it works

  1. Enumerate current users via the Admin SDK with a delegated service account.
  2. Construct and send individual emails to each user using the Gmail API.
  3. Log delivery attempts and failures per user for post-incident audit.
  4. Throttle sends to respect Gmail API quotas and avoid triggering account suspension.

What changes

Every user receives a direct, auditable message at their primary address, with delivery tracked and no reliance on pre-existing groups or lists.

The trap in this one. Gmail API enforces per-user and per-domain sending quotas that silently drop or defer messages when exceeded, with no immediate error in the API response. During a large incident, this means some users receive the email hours later or not at all, unless you explicitly monitor send quotas and handle deferred responses.

Questions people ask

Can I use group email addresses instead?

You can, but groups are often stale or misconfigured, and delivery to individuals cannot be tracked reliably. Per-user email is slower but auditable.

How do I know if a message was actually delivered?

The Gmail API provides message IDs for sent mail, but delivery failures (e.g., full mailbox, disabled account) are only visible via bounce messages in the sent mailbox, not in the API response.

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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