Stale Feature Flags (>90d, 100% rollout), PostHog

Stale Feature Flags (>90d, 100% rollout) for PostHog stores. Tracked live in Vortex IQ Nerve Centre. How to read it, why it matters, and how to act on it.

Metrics type: Supporting Metrics • Category: Analytics

At a glance

Stale Feature Flags (>90d, 100% rollout) is a feature-flags metric tracked from PostHog data. It counts flags that have been fully rolled out to 100% of users for more than 90 days. Each one is a cleanup candidate: the experiment is long over, yet the flag still lives in your code as a dead conditional branch. A growing count is flag debt, and this card is the queue for paying it down.

What it counts	The number of feature flags at 100% rollout for more than 90 days.
Sample type	Backend API data from PostHog feature-flag definitions, refreshed on the standard data refresh.
Why it matters	Stale flags are dead code that still has to be reasoned about, tested around, and maintained. Retiring them reduces risk and complexity.
Reading the value	Treat the count as a backlog. More than 5 stale flags is flagged as accumulating debt worth a cleanup pass.
Currency	count
Time window	RT
Alert trigger	>5
Sentiment key	ph_stale_feature_flags
Roles	owner, marketing

Calculation

Calculated automatically from your PostHog data. See the At a glance summary above for what the metric tracks and the worked example below for a typical reading.

Worked example

A representative reading of Stale Feature Flags (>90d, 100% rollout) for a typical merchant on PostHog. Suppose the card reads 7 stale flags, above the threshold of 5. Three of them, pdp-redesign, new-nav, and free-shipping-v2, hit 100% rollout back in early 26 and have not been touched since. Each is now permanently-on logic that the codebase still branches on. The card is the prompt to remove the flag references in the next cleanup sprint. Cross-reference Active Feature Flags for the full estate and Feature Flag Rollout Status for the current percentages. For deeper investigation, use Vortex Mind to trace upstream causes; for natural-language exploration, ask Ask Viq.

Sibling cards merchants should reference together

Card	Why merchants reach for it
ph_active_feature_flags	Feature Flags sibling: the full live estate.
ph_feature_flag_rollout	Feature Flags sibling: per-flag rollout percentages.
ph_health_score	Executive sibling: overall tracking health.
ph_dau	Executive sibling: the audience flags affect.
ph_event_volume	Executive sibling: total event volume.

Reconciling against the vendor’s own dashboard

Where to look in PostHog’s own dashboard:

In PostHog, open the Feature Flags list and sort by rollout percentage and last-modified date. Flags at 100% that have not changed in over 90 days are the stale ones this card counts. PostHog records each flag’s creation and last-modified timestamps, which drive the 90-day test.

Why the Vortex IQ value may legitimately differ:

Reason	Direction	What to do
Last-modified vs rollout-reached. The 90 days may count from last edit, not from when 100% was reached.	Variable	Confirm which timestamp is used.
Cohort conditions. A flag at 100% within a cohort is not globally 100%.	Variable	Inspect the release condition.
Recent edits. A trivial edit resets the staleness clock.	Variable	Check the last-modified date.

Cross-connector reconciliation: complement with sibling cards in the same category for the full diagnostic picture. For divergence investigations, use Vortex Mind.

Known limitations / merchant FAQs

Q: How often does Stale Feature Flags (>90d, 100% rollout) update? The card refreshes on the standard data refresh (typically every 30-60 minutes for live integrations). For real-time signals, force a manual refresh from the dashboard.

Q: Why retire a flag that is working fine at 100%? Because the code still branches on it. Every stale flag is a conditional that must be tested, reasoned about, and maintained forever. Removing it simplifies the codebase and reduces the chance of an accidental toggle.

Q: A flag I just cleaned up still shows. Why? Disabling or deleting the flag in PostHog clears it on the next refresh. If you only removed the code references but left the flag live in PostHog, it still counts. Remove both.

Q: Can I customise the alert threshold? Yes, alert thresholds are configurable per profile in the Alert Rules tab. Adjust to match your business baseline rather than relying on the generic default.

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Tracked live in Vortex IQ Nerve Centre

Stale Feature Flags (>90d, 100% rollout) is one of hundreds of KPI pulses Vortex IQ tracks across PostHog and 70+ other ecommerce connectors. Nerve Centre runs the detection layer; Vortex Mind investigates the cause when something moves; Ask Viq lets you interrogate any number in plain English.

Start for free or book a demo to see this metric running on your own data.