# Changelog - Jun 17, 2026

**Documentation:** https://docs.composio.dev/docs/changelog/2026/06/17

## PostHog connections: set your data region (US or EU) per connection

The PostHog region is now a per-connection setting. Existing connections keep their current region, so nothing changes for you.

The PostHog **region** (`us` or `eu`) now lives on the **connection** instead of the auth config. Region is genuinely per-connection — different users can sit in different PostHog regions — so fixing it at the auth config forced everyone through one region. Each connection now carries its own.

You don't need to do anything. We migrated every existing connection with no re-auth: connections on the default (`us`) stay on `us`, and any that used another region such as `eu` keep that value.

### Going forward [#going-forward]

* Set `us` (US Cloud) or `eu` (EU Cloud) on the connection. The host is built as `<region>.posthog.com`, so a full URL won't work and self-hosted PostHog isn't supported.
* **[Link flow](/reference/api-reference/connected-accounts/postConnectedAccountsLink)**: the Region field appears when the user connects, prefilled with your default and editable.
* **[Initiate flow](/reference/api-reference/connected-accounts/postConnectedAccounts)**: you set the region, and the end user never sees it.

### Setting a default on your auth config [#setting-a-default-on-your-auth-config]

An auth config's region default lives in its `shared_credentials`. If you were on the default (`us`), nothing was written there. To pin a region explicitly, set `shared_credentials` when you [create an auth config](/reference/api-reference/auth-configs/postAuthConfigs), or [patch an existing one](/reference/api-reference/auth-configs/patchAuthConfigsByNanoid).

See the [PostHog toolkit docs](/toolkits/posthog) for the current connection fields.

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