> ## Documentation Index
> Fetch the complete documentation index at: https://docs.letterbucket.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Caching

> Read caching behavior and automatic invalidation on writes.

`GET` responses for a single subscriber and for subscriber lists are cached for up to **1 hour**.

## What this means for you

* After creating, updating or unsubscribing a subscriber, the relevant cached reads are
  invalidated automatically, so your next read reflects the change.
* In the absence of a write, a `GET` may return data up to 1 hour old.

| Mutation          | Invalidates             |
| ----------------- | ----------------------- |
| Create subscriber | Subscriber lists        |
| Bulk create       | Subscriber lists        |
| Update subscriber | That subscriber + lists |
| Unsubscribe       | That subscriber + lists |