Smart Contract Infrastructure for Blockchain-Based Identity Systems

Project background 

Overview

Our client was developing a blockchain-based identity management system to let users register and control their own digital identities on Ethereum. The idea was to create a decentralized alternative to traditional authentication methods, where users could manage their identities without relying on central authorities. The system relied on smart contracts to handle identity registration, ownership, and verification. 

However, the existing contracts were unfinished and contained security vulnerabilities that could lead to unauthorized access or high transaction costs. Additionally, there was no standardized way for third-party applications to interact with these identities, making adoption difficult. Our goal was to rewrite the smart contracts, develop a secure Web3 API, and build an identity management dashboard for users.

Project Goals

• Build secure and gas-efficient smart contracts for decentralized identity management.
• Automate smart contract interactions to enable seamless integration with third-party applications.
• Improve Web3 authentication, allowing users to sign transactions securely through multiple wallet providers.
• Provide a simple and scalable interface for users to register, manage, and verify their blockchain-based identities.

Challenges

• The initial smart contract code was incomplete and had security flaws, requiring a full audit and redesign.
• Gas fees were too high, making identity registration and updates costly for users.
• The platform only supported Metamask, limiting accessibility for users with other Web3 wallets.
• There was no API for external applications, forcing dApps to interact directly with the blockchain, which was inefficient and complex.

Our approach

Solution

We rewrote and optimized the smart contracts, adding proper access controls and transaction validation to prevent unauthorized actions. Gas usage was reduced by optimizing contract logic, ensuring users paid lower fees when registering or managing identities.

To improve developer adoption, we built a Web3 API in Node.js, allowing third-party applications to verify user identities without making direct blockchain calls. This made integration easier and improved performance by reducing unnecessary on-chain interactions.

For users, we created a React-based identity management dashboard, where they could register, modify, and verify their blockchain-based identities. We also expanded authentication options beyond Metamask, adding support for WalletConnect and hardware wallets, making the system more accessible.

Team

The project was executed by a blockchain security engineer, smart contract developer, and Web3 full-stack engineer. The blockchain engineer focused on smart contract security and gas optimization, while the full-stack team developed the identity dashboard and API integration tools.

Results

We successfully deployed a secure, gas-efficient identity management system, allowing users to register and verify identities on Ethereum while keeping full control over their data.

The smart contract audit eliminated security vulnerabilities, preventing unauthorized identity transfers and reducing transaction costs. The Web3 API made it easier for dApps and external services to integrate identity verification without direct blockchain interactions. The new dashboard provided a user-friendly way to manage identities, supporting multiple wallet providers for authentication.