Signals ≠ Segment wrapper

Summary

A single event pipeline that carries three kinds:

• product — user did a thing (like Amplitude).
• health — service is (un)healthy (like Datadog metrics).
• delta-native — auto-emitted lifecycle events (delta.advanced, gate.signed, flag.exposed).

All three feed the same charts, and all three can gate a delta's rollout.

Why it matters

The trap we're avoiding. Every "developer platform" that touches analytics ends up as a UI over Segment/Amplitude. The moment you do that, three things break:

1. Your schema is Segment's schema — no delta linkage.
2. You have no story for health/error signals (Sentry, Datadog).
3. Customers pay Segment AND you.

Implications

Consequence. No 3rd-party CDP. @trunk/signals owns the schema. sdk-js / sdk-node / sdk-react are thin emitters. Server ingest is ours.

Related

• flag-shapes
• 2026-07-23-drizzle-over-prisma (events table lives in Postgres for v0).

Sources

• The memory note signals-vs-segment, written 2026-07-23 and moved here on 2026-10-04. The text is the note's own; only the headings changed.
• Recorded with delta D-0003.