Abstract

The advent of blockchain technology has revolutionized the way decentralized applications (dApps) and smart contracts are developed and deployed. However, the barrier of gas fees continues to hinder mass adoption, especially in resource-constrained environments. This paper proposes a novel, practical model for gasless smart contract transactions by integrating facial recognition technology within blockchain ecosystems. Our approach leverages zero-knowledge proofs and meta-transaction protocols to enable trustless authentication and transaction signing through biometric facial data, thereby eliminating the need for users to maintain a cryptocurrency balance for transaction execution. The proposed model is built on a multi-layered architecture that incorporates a decentralized identity (DID) framework, a biometric verification engine, and a relayer network that pays the gas on behalf of the user. Using facial recognition as a biometric key, users can trigger and authorize smart contract functions without direct wallet interaction or private key exposure. The system enhances security by utilizing advanced liveness detection and encrypted facial signature hashing, preventing spoofing and ensuring that only legitimate users gain access to the network. Furthermore, it supports user onboarding via identity verification processes that comply with global KYC (Know Your Customer) standards, thus bridging the gap between user accessibility and regulatory requirements. A simulation environment was developed using Solidity, OpenZeppelin libraries, AWS Rekognition for facial analysis, and the Biconomy SDK for meta-transactions. Performance metrics indicate significant improvements in user onboarding time, cost-efficiency, and fraud prevention compared to traditional models. The model also reduces environmental impact by lowering the computational overhead associated with repeated gas-based authentication. This paper provides a blueprint for developers, policymakers, and fintech stakeholders to adopt gasless blockchain frameworks supported by biometric security. It presents a scalable and user-friendly solution that could unlock broader blockchain adoption in finance, healthcare, and identity management sectors. The fusion of facial recognition with smart contract automation signifies a leap towards a more inclusive, secure, and cost-efficient decentralized future.