Liquidation bots or keepers in DeFi are important automated agents that maintain the financial health and solvency of lending and margin trading protocols. The on-chain lending and margin trading systems rely extensively on collateral-backed loans; this means users borrow assets by locking in cryptocurrency as security. If market volatility pushes down the value of that collateral, such a shift must be responded to immediately by the protocol.
This is where liquidation bots come into play. They constantly monitor the collateral ratios, identify risky positions, and execute liquidations in less than a few seconds to avoid bad debt. As DeFi evolves with things like lending, derivatives, and DeFi Margin Trading, the work of liquidation bots becomes even more important.
Introduction: Why Liquidation Bots Matter in DeFi
DeFi cuts out the human middlemen and replaces them with smart contracts. This affords transparency and permissionless access but also makes risk management completely automated. Whereas banks have credit departments and manual checks to make sure loans remain secure, DeFi protocols have to rely on code-driven mechanisms.
Under-collateralization is one of the most significant risks that DeFi lending carries: when the collateral's value falls below the value of the asset borrowed against it, creating a bad debt that, if left unhandled, can leave liquidity providers with unrecoverable losses.
Liquidation bots exist for this very purpose.
They maintain system solvency by:
Real-time monitoring of borrowers' positions
Automatic liquidation of unhealthy loans
Making sure the protocol is always over-collateralized
Protecting the lending pool and its participants
Long-term stability of the protocol
Lending platforms, stablecoins, and leveraged trading systems collapse without liquidation bots in case of severe price swings.
What Exactly Are Liquidation Bots (Keepers)?
Liquidation bots, typically referred to as keepers, are autonomous agents interacting directly with DeFi protocols on-chain. They seek to identify whenever a borrower's collateral ratio falls below the safety limit, after which they take immediate action.
Characteristics of Liquidation Bots
1. Autonomous Operation
Their scripts are running 24/7, always scanning real-time market data, oracle feeds, and smart contract events. Because crypto markets never sleep, neither can the bots.
2. Permissionless Participation
Anyone who is capable technically can run a bot. This decentralization ensures that no single entity monopolizes liquidations, hence making the ecosystem even more secure.
3. Competitive Structure
Multiple bots compete to liquidate positions. The fastest bot earns the liquidation reward, creating a natural incentive for performance, optimization, and uptime.
4. Incentive Alignment
Liquidators earn bonuses-through liquidation penalties paid by borrowers-or fees for executing the liquidations. These rewards ensure constant participation even during peak volatility.
5. Programmed for protocol-specific rules
Liquidation thresholds differ between different lending protocols, as do penalty sizes and execution formats. Bots are programmed to follow each protocol's unique rules precisely.
Liquidation bots represent the "first responders" of DeFi's ecosystem risk management framework.
How Liquidation Bots Maintain System Solvency
System solvency essentially means the protocol has enough collateral backing against all outstanding loans. If undercollateralized borrower positions go unnoticed, significant losses could occur to the protocol.
Liquidation bots avoid this by performing a structured lifecycle of monitoring and liquidation.
Liquidation Process Steps
Step 1: Continuous Monitoring
Bots constantly monitor smart contracts in charge of:
Borrowing balances
Collateral values
Oracle price updates
Collateralization thresholds
If the price of collateral falls, the bot detects a potential risk.
Step 2: Comparing Collateral Ratios
Each loan must keep a minimum collateral ratio, such as 150%, 125%, etc.
A bot calculates:
Collateral Value ÷ Borrowed Value
If the result goes below the minimum set by the protocol, the position becomes liquidatable.
Step 3: Liquidation Triggering
Once the condition is met, the bot sends a transaction that calls the liquidation function of the protocol.
This needs to be done expeditiously to avoid:
Oracle price delays
Competitor bots beating them
Collateral value dropping further
Step 4: Selling or Auctioning Collateral
Depending on the protocol, the system:
Sells collateral at a discount
Auctions collateral to bidders
Transfer collateral to liquidators
Bots participate in each model accordingly.
Step 5: Repayment of Outstanding Debt
Liquidated collateral is used to repay the protocol's debt. This ensures:
The lending pool remains solvent
Lenders never incur unrecoverable losses.
Step 6: Receival of Liquidation Rewards
As reward for this crucial service, the bot receives:
A liquidation bonus
Keeper rewards
Stability fees, in some systems
This aligns financial incentives with protocol safety.
Step 7: Restoration of Protocol Solvency
Liquidating unfavorable positions ensures that:
All loans remain fully collateralized
No bad debt accumulates
System-wide stability is maintained during crashes.
This is the backbone of DeFi risk management.
Why do DeFi protocols rely on liquidation bots?
Unlike traditional financial institutions, DeFi systems are unable to negotiate, restructure loans, or call borrowers manually. Everything is handled by code.
This is why liquidation bots are indispensable.
Liquidation Bots Are Critical
1. Real-Time Risk Management
Bots respond instantly to changes in prices. For instance, if ETH drops 10% in five minutes, bots need to immediately liquidate thousands of positions.
2. Protection of Lenders and Liquidity Providers
Protocols like Aave and Compound require user-supplied liquidity. Liquidators protect these lenders from losses.
3. System Stability
Unexpected insolvency events destroy trust. Bots ensure predictability and transparency in finance.
4. Decentralization
Multiple independent liquidators prevent any one agent from controlling the stability mechanisms of the protocol.
5. Stress-Tested Resilience
During events like crypto crashes or exchange collapses, such as those with FTX, bots act as the protocol's emergency response mechanism. Without them, liquidation queues would build up, and protocols would collapse.
Where Liquidation Bots Operate
Liquidation bots fit into a number of categories in DeFi, considering the involvement of collateral and leverage.
They operate on:
Lending protocols: Aave, Compound
Stablecoin mechanisms: MakerDAO's DAI
Synthetics platforms - Synthetix
Perpetual futures platforms: dYdX, GMX
DeFi Margin Trading platforms that leverage collateralized positions
As DeFi expands across chains, it's seeing more and more cross-chain liquidation bots.