Pegged Orders

A pegged order (type: "peg") tracks a reference price and automatically reprices when that reference moves. Instead of placing a limit at a fixed price and manually adjusting it as the market shifts, a peg follows the market for you.

Peg References

Pegged orders use a single type with a peg_reference field:

`peg_reference`	Tracks	Typical use
`mid`	Midpoint of best bid and best ask	Resting inside the spread to capture price improvement on both sides
`bid`	Current best bid	Passive liquidity on the bid, tracking the top of book
`ask`	Current best ask	Passive liquidity on the ask, tracking the top of book

How It Works

When the reference price changes (e.g. a new best bid arrives), the matching engine reprices all pegged orders tied to that reference. Repricing happens within the MPC matching cycle — the same latency as any other order operation.

A peg order does not accept a price field. The effective price is derived from the reference at match time.

Pegged orders compose with time_in_force and aon the same way limit orders do: a mid-pegged GTC order rests indefinitely and reprices on every midpoint move; a mid-pegged IOC attempts an immediate fill at the current midpoint and cancels any unfilled remainder.

Example — Peg to Mid

{
  "symbol": "BTC-USDC-PERP",
  "side": "buy",
  "type": "peg",
  "peg_reference": "mid",
  "quantity": 0.1,
  "time_in_force": "GTC"
}

Example — Peg to Bid (Passive)

A buy order pegged to the bid sits at the front of the queue on the buy side without ever crossing the spread:

{
  "symbol": "BTC-USDC-PERP",
  "side": "buy",
  "type": "peg",
  "peg_reference": "bid",
  "quantity": 0.1,
  "time_in_force": "GTC"
}

Modifying Pegged Orders

PATCH /orders/{orderId} accepts quantity changes on pegged orders but not price — the effective price is fixed by peg_reference. To change reference tracking, cancel and re-place.

See Order Compatibility for supported TIF and attribute combinations.