Nexus DEX — Building & Deploying a Full-Stack Web3 DEX on SCAI Mainnet

NIVAS B.U — Mon, 25 May 2026 15:11:17 +0000

As part of my Web3 internship training, I built and deployed Nexus DEX, a decentralized exchange running on the SecureChain AI (SCAI) Mainnet.

The project involved implementing smart contracts, wallet connectivity, frontend integration, liquidity handling, and live blockchain interaction using Solidity, React.js, Hardhat, and Ethers.js.

Tech Stack

Solidity
Hardhat
React.js
Ethers.js
OpenZeppelin
Tailwind CSS
Vercel

Features Implemented

ERC20 token smart contract
Token swapping
Liquidity pool system
MetaMask wallet integration
Live transaction handling
Dashboard analytics
SecureChain AI Mainnet deployment
Multi-wallet testing across devices

Smart Contracts

NXSToken Contract

ERC20 utility token powering the protocol.

0xb636D73a75c5617FeCF034F028CbC5c597107586

NexusSwap Contract

Handles swapping and liquidity operations.

0xcbCC2968592A9283168B80ECEA311962b7101fFC

Multi-User Testing

One of the most interesting parts of the project was testing the DApp across multiple wallets, browsers, and devices after deployment.

The complete onboarding/testing flow was:

Add SecureChain AI Mainnet to MetaMask
Faucet SCAI tokens
Import the NXS token contract into MetaMask
Connect wallet to Nexus DEX
Swap SCAI → NXS
Add liquidity using received NXS tokens

During testing, I verified that liquidity state updates synchronized globally across all connected users.

Whenever liquidity was added from one wallet, the Pool Analytics section updated across every active device interacting with the DApp.

This helped me better understand:

shared blockchain state synchronization
frontend ↔ smart contract consistency
wallet onboarding UX
transaction lifecycle handling
decentralized application state management

Runtime Issues & Debugging

The biggest learning experience came from debugging real-world Web3 runtime issues.

Some of the problems I encountered included:

ERC20 approval failures
insufficient gas balance errors
transaction execution failures
MetaMask synchronization issues
dashboard state inconsistencies
frontend deployment routing problems
liquidity validation edge cases

To fix these issues, I implemented:

transaction confirmation handling using await tx.wait()
frontend reload synchronization
wallet balance validation
gas safety checks
improved dashboard synchronization
multi-wallet testing flows

This debugging phase taught me significantly more about Web3 engineering than isolated smart contract tutorials.

Live Deployment

Final Thoughts

Building Nexus DEX helped me understand the complete lifecycle of a deployed decentralized application — from smart contract development to frontend integration, transaction execution, deployment, debugging, and multi-user interaction on a live blockchain network.

A large portion of development effort involved runtime debugging, transaction analysis, and frontend ↔ blockchain synchronization across real user environments.

Overall, this project was a valuable hands-on experience in full-stack Web3 development.

Web3 #Blockchain #Solidity #ReactJS #Hardhat #DeFi #SmartContracts #EtherAuthority

DEV Community: NIVAS B.U