Case Study: Chainlink Functions Demo dApp

Introduction

The Chainlink Functions Demo dApp is an exemplary showcase of HackBG‘s expertise in full-stack blockchain application development. This project, hosted on the Fuji testnet (Avalanche), leverages the power of Chainlink Functions to demonstrate a practical implementation of smart contract technology. It serves as an interactive guide on how Chainlink Functions operate, featuring real smart contract code and user-friendly documentation on its mechanics.

Project Specifications

• Functionality: The dApp enables users to query a city’s temperature using a web2 API (Open-Meteo) and records this data on-chain through a smart contract.
• Development Aspects: HackBG‘s role spanned across several domains including the development of smart contracts, backend server components using Next.js, and front-end implementation with Next.js 13.
• Integration: The project integrates with various technologies and services, including Chainlink Functions, while managing backend wallet interactions efficiently.
• Technological Stack: The project was built using a range of technologies such as Solidity, Hardhat, Redis, along with Next.js and TypeScript.

Development Process

• The project was developed by a team of two developers over a three-week period, reflecting HackBG‘s efficiency and skill in blockchain development.
• HackBG‘s collaboration with Chainlink is in its third year, focusing on building a comprehensive library of tools and applications for easy integration with Chainlink’s oracle network.

Unique Features and User Experience

• Demo Purpose: The dApp serves as a demo project on the Chainlink network, providing real-world examples and a ready-to-use quick start template for developers. They can fork this project to develop their own applications, with the ability to customize API integrations and contract functionalities.
• Ease of Use: A backend API service was integrated to cover the gas fees for all requests, making it a cost-free experience for developers to explore the dApp’s functionalities. This decision was deliberately made to foster experimentation and learning, eliminating the need for wallet connection and transaction.
• Operational Flow: Users select a city, and the Chainlink oracles receive the request. They execute the embedded code in the contract (an Open-Meteo API request in this case) to fetch the temperature data and send it back on-chain. The returned result is cryptographically signed, ensuring its validity via a consensus among the Chainlink network oracles.

Technological Innovation and Impact

This project is a testament to our ability at HackBG to transform complex blockchain functionalities into accessible and practical applications. It showcases not only our technical prowess but also our commitment to contributing to the broader blockchain developer community by providing a versatile and comprehensive dApp demos.

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