Customer comms as an engineer

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_ids

Prior art to mirror: the feature-flags quota-limit rollout in product-internal#720.

For the underlying email infrastructure (Customer.io tags, categories, unsubscribe behavior), see the email comms handbook page. For incidents specifically, see engineering incidents — Marketing handles those comms too.

Staying on top of what ships

If you write or coordinate customer comms, join the #changelog internal Slack channel — it's the lowest-friction way to know what's just shipped. It's owned by the Wizard & Docs team and updated constantly as PRs merge.

The channel is populated by agentic workflows that scan merged PRs and feature flag changes in posthog/posthog and summarize them into it. You can opt a PR in or out via the Publish to changelog? checkbox on the PR template, or via the @posthog Slack app. See how to publish changelog for the full flow.