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

# Order lifecycle

> Every way an order ends, and exactly what still works when trading is paused or the feed goes down.

## States

| State         | How it is reached                                               |
| ------------- | --------------------------------------------------------------- |
| **Open**      | Escrowed, in both index sets, fillable while the clock runs     |
| **Filled**    | `sellRemaining == 0`; de-indexed automatically on the last fill |
| **Cancelled** | The order is closed and its remainder is refunded to the maker  |
| **Expired**   | Its deadline passed and the remainder was refunded to the maker |

`orderStatus` reports **Expired** for an order that is still `Open` in storage but past its
deadline, so a reader never has to compute that themselves.

## Expiry and refunds

After an order's deadline, anyone may trigger its expiry. The remaining escrow always goes back to
the maker, and expiry remains available while trading is paused.

## What a pause stops

| Action                    | Paused    |
| ------------------------- | --------- |
| Create an order           | blocked   |
| Fill an order             | blocked   |
| Cancel or expire an order | available |

## What an unusable reference price stops

| Action                  | Stale feed or unavailable five-minute average |
| ----------------------- | --------------------------------------------- |
| create, either kind     | blocked                                       |
| fill a **Pegged** order | blocked                                       |
| fill a **Fixed** order  | works                                         |
| cancel · expire         | works                                         |

A pegged order has no price of its own, so pricing it from a stale or under-sampled average is
exactly the thing worth refusing. A fixed order's ratio was locked at creation and needs nothing
from the feed.

<Check>
  No **Rondo control path** disables an exit. Cancellation remains callable regardless of the oracle,
  protocol pause, or whether the maker still holds `MAKER_ROLE`. If a token transfer is unavailable,
  the refund waits until the transfer can complete.
</Check>

## Enumeration has a sharp edge

`EnumerableSet.remove` swaps the **last** element into the freed slot. So an order cancelled between
two page reads slides *backwards* into a page the reader has already passed, and is never seen —
while still being open and fillable.

<Warning>
  Any consumer paging the open set must read **every page at one pinned block**. The reference
  interface reads count, id pages and order data as a single block-pinned query for exactly this
  reason.
</Warning>