Product analytics boundary
Embed
<a href="https://watchtowerops.net/docs/analytics-boundary"><img src="https://watchtowerops.net/docs/_api/public/orgs/aa5959cb-1a0b-4a9a-bc9a-913e7ac31cd9/spaces/b7aac181-9916-4805-b253-becc5fd2ca62/pages/b56d5d57-1105-48fa-830a-8ce29123018d/social-card.svg?v=3e7ae33eec8b" alt="Product analytics boundary" width="600" height="315"></a>Watchtower is an observability platform. Product analytics (funnels, retention, cohorts, feature flags, experiments, session-based growth metrics) is not built here: teams use PostHog for it and Watchtower links to it.
What Watchtower does
Stores errors, traces, logs, metrics, RUM and replays, and links them to each other and to releases.
Accepts deploy and feature-flag change events as annotations (
change_events), so a regression can be tied to a flag flip. Flags are read, never evaluated or served.Offers deep links from a user, session or issue to the matching PostHog person or recording when the project sets a PostHog base URL (
docs/product/deep-links.md).PostHog connector (CON-007): a
posthogreceiver pushes issue, alert and incident events to PostHog's/capture/(event subscriptions,docs/product/notifications/channels.md), and with a sealed personal API key (PUT /v1/projects/{prj}/rum/posthog/key, write-only, audited) the session page reads the person's scalar properties live from PostHog (GET .../rum/posthog/person?distinct_id=, needs the replay permission). Nothing read from PostHog is stored.
What Watchtower does not do
No funnels, retention curves, cohorts, paths or experiments.
No feature-flag service or experiment assignment.
No product-usage dashboards. Usage metering (
docs/product/usage.md) counts platform consumption (bytes, records, queries), not end-user behaviour.
How this is checked
The parity matrix excludes these features with the PostHog reference (docs/research/parity/excluded.yaml), and cd go && go run ./tools/parity validate fails if an excluded feature is represented as built.