Driver API
The Driver service acts as a bridge between Autopilot and solver engines, handling liquidity aggregation, solution transformation, simulation, and on-chain settlement for CoW Protocol auctions.
Primary Responsibilities
The Driver manages several critical functions:
- Liquidity Collection: Fetches AMM pools, limit orders, and other liquidity sources
- Auction Translation: Converts autopilot auction format to solver-compatible format
- Solution Encoding: Transforms solver solutions into settlement calldata
- Simulation: Validates solutions before on-chain submission
- Gas Estimation: Computes accurate gas costs for solutions
- Settlement Submission: Broadcasts winning solutions to the blockchain
- Monitoring: Tracks transaction status and settlement outcomes
API Endpoints
POST /solve
Accepts auction requests from Autopilot and returns computed solutions with scoring details, execution specifications, and gas estimates.
POST /reveal
Exposes settlement calldata for shadow competition verification, providing both “internalized” (on-chain version) and “uninternalized” (simulation-ready) variants.
POST /settle
Instructs the Driver to submit winning solutions on-chain, executing encoding, simulation, signing, and broadcast operations.
GET /quote
Delivers price estimations for individual orders, supporting both legacy and JIT-enabled response formats.
POST /notify
Receives solver status change notifications from Autopilot.
Solution Architecture
Solutions contain:
- Identifiers and objective scores
- Submission addresses
- Order execution mappings
- Mapping of token address to uniform clearing price
- Gas cost projections
- Detailed per-order execution information
Liquidity Sources
The system integrates five primary liquidity categories:
- Constant product pools (Uniswap V2-style)
- Weighted product pools (Balancer)
- Stable pools (Curve)
- Concentrated liquidity (Uniswap V3)
- Foreign limit orders (0x-style)
Internalization Feature (CIP-2)
Solvers optimize costs by utilizing settlement contract token buffers rather than routing through AMMs. This results in two calldata versions:
- Internalized: The on-chain version that uses buffers
- Uninternalized: The simulation version with full AMM routing
Configuration and Best Practices
The Driver operates through TOML-based configuration managing solver engines, liquidity sources, and settlement parameters.
For production reliability:
- Ensure accurate gas estimation
- Comply with deadlines
- Perform thorough pre-submission simulation
- Maintain detailed error logging
- Monitor performance metrics continuously
Last modified on March 4, 2026
