Consent-on-Chain – Verifiable Consent Management with Smart Contracts

An Ethereum-based system to manage, validate, and audit digital consent artifacts directly on the blockchain.

Date: February 2025
Client: Self-initiated
Role: Full-stack Blockchain Developer
BlockchainEthereumSmart ContractsConsent ManagementAPIs

Overview

Consent-on-Chain is a smart contract-backed system for secure consent artifact lifecycle management. It provides API endpoints for uploading, validating, downloading, revoking, and auditing user consents via the blockchain, ensuring tamper-proof verification and compliance transparency.

Key Features

FunctionDescription
Upload ConsentRecords hashed consent artifacts to the smart contract
Verify ConsentValidates if a consent artifact exists and is active
Revoke ConsentMarks a consent as revoked with timestamp logging
Download & LogsProvides all historical records for auditing purposes

Tech Stack

TechUsage
SoliditySmart contract development
Node.js & ExpressAPI integration with blockchain
HardhatTesting and deployment framework
Polygon Amoy TestnetDeployment network

Warranty-on-Chain – NFT-Backed Warranty System for eCommerce

A blockchain-based warranty tracking system using NFTs, built for Flipkart Grid 5.0 by Team Devloopers.

Date: October 2024
Client: Flipkart Grid Hackathon
Role: Blockchain Engineer & Architect
BlockchainNFTeCommerceWarrantyHackathon

Overview

Warranty-on-Chain is a full-stack solution that issues warranty cards as NFTs upon product purchase. These NFTs store product details, ownership history, and warranty validity directly on-chain, ensuring trust, transparency, and easy claim handling for users and retailers alike.

Key Features

FeatureBenefit
NFT Warranty CardsTrack ownership, claims, and serial numbers on-chain
OTP VerificationAuthenticates customers using phone + serial combo
Warranty ClaimingAllows users to raise, extend, and track claims
GamificationSuperCoins and leaderboard for incentivization
Soulbound NFTsLoyalty-based non-transferable rewards

Use Cases

- P0: Prove ownership of products via blockchain - P1: View live warranty status and claim history - P3: Raise or extend claims via smart contract - P5: Transfer product NFTs during resale - P10: View SuperCoin leaderboard for rewards

Tech Stack

TechnologyPurpose
SoliditySmart contract for NFT-based warranties
Chainlink KeepersAutomated warranty expiry checks
React + Node.jsWeb portals for retailers and users
IPFS + RinkebyMetadata storage and testnet deployment