How to Build an Intent-Based DEX Aggregator With Solver and Filler Networks

CoW Protocol describes this as a two-stage optimization problem: solvers first determine optimal routing and then optimize their bid for the auction.

This distinction is critical when designing a modern DEX Aggregator Development Company solution. The core product is no longer “find the cheapest DEX route.” It is find and settle the best executable outcome.

Why Solver and Filler Networks Matter

The most important architectural change is separating order creation from order fulfillment.

A solver can examine:

• DEX liquidity
• Aggregator APIs
• RFQ liquidity
• Private market-maker inventory
• Cross-chain liquidity
• Coincidence-of-Wants opportunities
• Gas costs
• Slippage
• MEV exposure
• Settlement constraints

The solver then submits a proposed execution.

Fillers perform a closely related but execution-focused role. In UniswapX, fillers compete to satisfy signed orders using their own strategies and can use on-chain liquidity or private inventory.

For a DEX Aggregator Development Company, supporting both models creates a broader liquidity marketplace instead of depending on a single routing algorithm.

Core Architecture of an Intent-Based DEX Aggregator

A practical architecture should contain six major layers.

1. Intent Layer