# Customer comms as an engineer - Handbook

Got a service change you need to email customers about — an API deprecation, a new quota limit, a breaking SDK change, a migration deadline? **Loop in Joe.** He owns customer comms and will handle the copy and the send via Customer.io.

All you need to bring:

-   A rough draft of what you want to say and why
-   The audience: a PostHog cohort or a list of `org_id`s

Prior art to mirror: the feature-flags quota-limit rollout in [`product-internal#720`](https://github.com/PostHog/product-internal/pull/720).

For the underlying email infrastructure (Customer.io tags, categories, unsubscribe behavior), see the [email comms handbook page](/handbook/brand/email-comms.md). For incidents specifically, see [engineering incidents](/handbook/engineering/operations/incidents.md) — Marketing handles those comms too.

### Community questions

Ask a question

### Was this page useful?

HelpfulCould be better