# Subscription System

> **Status: stub — Phase 1 (structure).** Content to be written in Phase 2.
>
> **Scope:** How subscriptions and filters work; live query delivery to clients.

## Outline

- Subscription model and filters
- Live delivery
- Limits and performance considerations

## Source material

- `ARCHITECTURE.md` §5 Subscription System
- `crates/buzz-pubsub`