Nexus DEX
Hybrid AMM + Order Book on Arbitrum
A full-stack decentralized exchange combining AMM liquidity pools with on-chain limit orders, ERC-2612 gasless approvals, and ERC-4626 staking vaults on Arbitrum L2.
Role
Solo Developer
Duration
2024
Team
Solo Project
Tech Stack
SolidityHardhatReactethers.jsArbitrumERC-2612ERC-4626TailwindCSSVite
Impact
Results & Metrics
1 tx
Gasless Approvals
Permit + swap in a single transaction
10-100x
L2 Costs
Lower fees via Arbitrum deployment
AMM + OB
Hybrid Liquidity
Combines pooled liquidity and limit orders
Problem
Challenges Faced
Hybrid Execution Routing
Needed to compare AMM quotes and order book depth to select the best execution path for every trade.
Gas-Efficient Order Book
On-chain limit orders require careful storage and matching logic to keep gas costs reasonable.
Frictionless UX
Reducing approval steps without compromising security or compatibility across wallets.
Solution
How I Solved Them
Smart Routing Logic
Implemented quote simulation for both AMM and order book paths to pick optimal execution.
Optimized Data Structures
Used gas-optimized linked list order storage and batching to reduce write costs.
Permit-Based Approvals
Integrated ERC-2612 permits to enable gasless approvals and single-transaction swaps.
Capabilities
Key Features
Hybrid AMM + order book trading
ERC-2612 permit approvals
ERC-4626 staking vaults
Liquidity pool provisioning
On-chain limit orders
Wallet connection and swaps
Price charts and order book UI
Arbitrum L2 deployment