PostHog

Open-source product analytics with event tracking, session recording, feature flags, and A/B testing.

POSTHOG_KEY=phc_...
POSTHOG_HOST=https://us.i.posthog.com  # or https://eu.i.posthog.com for EU

Note:

• You can set POSTHOG_KEY without the NEXT_PUBLIC_ prefix and Shipkit will automatically generate NEXT_PUBLIC_POSTHOG_KEY at build time for use on the client.
• The non-prefixed variable is not accessible on the client; only the generated NEXT_PUBLIC_* value is exposed.
• For self-hosted PostHog, set POSTHOG_HOST to your instance URL.

Get your project API key from PostHog Dashboard → Project Settings.