Glossary.

Every term, alphabetized loosely by importance rather than strictly. Click through to the full chapter when the one-liner isn't enough.

• event
  A typed payload that crossed the gate. Has an id, type, payload, source_id, and received_at timestamp. Immutable once stored.
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• source
  Where events enter the system. SDK source (bearer key), webhook source (unique URL + HMAC or bearer), or a native integration.
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• pipeline
  A definition that says which events trigger it, what actions run, and which destinations get the result. Versioned per deploy.
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• destination
  An egress target. Today: webhook.out. More to come.
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• entity
  One row of your identity graph — a person, account, order, anything keyed by an external_id you control. Has open-schema traits.
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• delivery
  One pipeline's run for one event. Carries status, attempts, and the last error if any.
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• action
  A step inside a pipeline. Fourteen kinds across three categories: enrichment, mutation, control.
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• template
  The $-rooted JSON-ish string the transform action renders. Substitutes $event / $entity / $enrich / $classify / $summarize / $translate / $ai / $http / now().
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• the gate
  Where every event is checked on the way in: auth, payload shape, dedupe, rate limit. An event that doesn't pass the gate is a 4xx, not a silent drop.
• dead
  Terminal delivery status. Reached after five failed attempts. Stays around for inspection.
• idempotency key
  Caller-provided key that dedupes identical sends within a window. Retries are free; deliberate replays cost.
• region
  Where your data lives. Frankfurt or Dublin currently; entities and events never leave the region they were stored in.
• org
  The tenancy boundary. Every API key, every row in every table, is scoped to one org. Cross-org access is structurally impossible, not policy-enforced.
• rev
  A pipeline's version number. Bumps every time you deploy. Older versions are kept for history.
• matcher
  The rule that decides which pipelines fire for an event. A pipeline matches when one of its active source rules names the event's type.
• short-circuit
  What a control action does when it drops the event. The pipeline marks the delivery delivered without dispatching to any destination.
• fan-out
  A pipeline running through every one of its destinations in parallel. Each gets its own (possibly redacted) body.
• redaction matrix
  redact.pii's config: per-PII-type, per-destination, what to do. Lets one pipeline send a masked email to Slack and a raw email to the warehouse.
• $-dialect
  The template syntax. Six rooted refs plus now(). Looks like JSON, parses as JSON after substitution.