Introduction

The Maker system provides various opportunities for profit which help to maintain market equilibrium. Strategies to arbitrage these opportunities can be codified as keepers - automated bots which can detect and trade inefficiencies across Dai Core, OasisDEX and various other exchanges.

It is expected that developers and operators will evolve their own keepers over time. Below you will find a list of our reference keepers.

Bear in mind that this page is just a brief summary of reference keepers and that you can find out more by reading individual keeper READMEs present in their GitHub repositories, or even by directly reading their source code which is usually quite well documented. We encourage developers to hack existing keeper implementations and to build new ones, either using the pymaker and pyexchange libraries or completely from scratch. Due to profit opportunities inherent to the Maker ecosystem we expect the keeper space to grow over time.

The community is always happy to answer your questions in the #keeper RocketChat channel.

bite-keeper

CDPs that fall below the safe collateralization ratio can be liquidated by any external agent via an operation known as bite.

The bite-keeper constantly monitors the Tub contract looking for unsafe cups and bites them the moment they become unsafe. In future versions, it will take into account the profit it can make by processing the liquidated collateral via bust and only waste gas on bite if it can make it up by subsequent arbitrage. For now, it’s just a dumb keeper that bites any cups that become unsafe.

arbitrage-keeper

The arbitrage-keeper performs arbitrage on OasisDEX, join , exit , boom and bust actions. It constantly scans for profitable arbitrage opportunities and executes them the moment they become available. It provides valuable source of information where to look for arbitrage opportunities in the Dai system and how to exploit them. It also supports atomic risk-free arbitrage via the tx-manager contract.

This keeper will not work with multicollateral Dai, mainly because boom and bust actions will not be present in it anymore. Instead of that, surplus and bad debt will be liquidated via auctions. Please see the auction-keeper below.

auction-keeper

The auction-keeper can participate in collateral ( flip ), bad debt ( flop ) and surplus ( flap ) auctions. It focuses mostly on interaction with the smart contracts and supports pluggable bidding models, so that one can easily build their own auction participation strategies while not having do deal with the low-level smart contracts and Ethereum stuff.

This keeper is currently early work in progress, but we plan to make it fully functional by the time of the multicollateral Dai launch.

market-maker-keeper

The market-maker-keeper is actually a set of keepers that facilitate market making on multiple exchanges. They all follow the same configuration principles, and almost all of them are capable of covering any DAI market provided an appropriate price feed is present.

As of today, the following exchanges are supported:

OasisDEX,

EtherDelta,

RadarRelay and ERCdEX (via Standard Relayer API),

Paradex,

DDEX,

Ethfinex,

GoPax,

HitBTC,

IDEX,

Bibox,

OKEX,

TheOcean,

gate.io.

cdp-keeper

The cdp-keeper is responsible for actively monitoring and managing open CDPs. In early versions it was only capable only of topping up CDPs at risk of falling below the liquidation level, but more functionality started being added to allow:

automatically wiping debt when approaching the liquidatio ratio

managing the dai volume to keep it within specific range

This keeper is still under development.