Stand up the experiment/feature-flag layer (Amplitude Experiment via the existing @amplitude/unified SDK): variant assignment, flag gating, holdouts, and the paired engagement + data-quality guardrail events that every gamification and ranking experiment reads.
Why this matters
The A/B harness is assumed everywhere (Entry 031, G-059) and exists nowhere in
code — ViewTracker only calls amplitude.track. Building it is small and
unblocks gamification (G-059) and search-ranking (G-063) experimentation alike.
Open decisions:
- Assignment & gating — initialize Amplitude Experiment on the existing
@amplitude/unifiedSDK; deterministic per-user variant assignment; server- and client-side flag evaluation; holdout groups. - Guardrail event model — make data-quality events (revert rate, contradiction-flag, consensus disagreement, rubber-stamp rate) first-class alongside engagement events, so a variant can't win on engagement while silently regressing quality (G-026, G-059).
- Readout discipline — encode the Entry 031 methodology: 30–60 day horizons, holdouts, and a pure-intrinsic arm to detect overjustification crowd-out.
- Change governance — who can launch/promote an experiment, and which surfaces (e.g. ranking, G-063) are constitutional-tier rather than unilateral.
Related
- Entry 032 — the bridge strategy that names this the first build
- Entry 031 — the gamification A/B thesis this enables
- G-059 — gamified contribution (the primary consumer; blocked by this)
- G-063 — entity search ranking (the other experiment consumer)
- G-026 — Fact-graph data quality (the guardrail events)
- G-010 — discoverability & recommendation (experiment surface)