Learn about dApps

Evolution Of dApp Development: A Comprehensive Overview

by Ross Bose

Currently, decentralized applications (dApps) are the main attractions within the crypto and blockchain ecosystem. These applications operate independently from centralized servers and backend technologies. Instead, they utilize Web3 technologies to handle logic execution and other backend functions. The demand for tutorials and guides on dApp development has increased significantly due to the desire for immutable and tamper-proof security.

While many existing guides on dApp development primarily cover the fundamental prerequisites and provide a high-level overview of the essential steps, this post presents a technical guide. It details the process of constructing basic end-to-end decentralized applications that can retrieve and store existing ETH prices using smart contracts.

Why Learning About dApp Development Is Critical

Understanding the concept of decentralized application (dApp) development offers valuable insights into the world of dApps. Unlike traditional applications, dApps have their backend code stored on decentralized blockchain networks rather than centralized servers.

However, the frontend logic and user interfaces of dApps can be developed using any programming language, and they can interact with the backend logic through desired servers. The backend programming logic of dApps resides in smart contracts, ensuring immunity to tampering and providing robust security.

Learning dApp development brings numerous advantages, making it a worthwhile endeavor. First and foremost, dApps offer enhanced privacy, reduced downtime, and resistance to censorship. Additionally, they establish a trustless environment for executing logic, which is a key benefit.

Nevertheless, it is crucial to adopt effective practices for blockchain dApp development to navigate the potential challenges. For instance, running logic across a distributed ledger incurs overhead compared to centralized servers. Moreover, user experience aspects differ significantly between decentralized applications and traditional ones.

Key Components in dApp Development

When delving into the technical aspects of dApp development, it is crucial to understand the essential components that form the architecture of a decentralized application. The following components are necessary when building a dApp:

Smart Contract:

Smart contracts play a vital role in dApp development, enabling the inclusion of unique functionalities. These contracts encapsulate the business logic and application state within a decentralized application. They are programmed onto the blockchain network.

Frontend Logic and User Interface:

While the backend development of dApps involves scripting smart contract logic for deployment on the blockchain, developers can utilize familiar technologies such as JavaScript and HTML for frontend logic.

Traditional Web2 tools, frameworks, and libraries can be leveraged for dApp development. The user interface (UI) is also a significant component, connecting with smart contracts through client-side libraries. Examples of such libraries include Web3.js and Ethers.js, which can be bundled with frontend resources and sent to the browser along with the UI.

Data Storage:

The choice of a dApp development platform depends on the data storage requirements. On-chain data storage in a decentralized manner can be expensive, necessitating the use of off-chain storage systems. IPFS (InterPlanetary File System) is one such solution that allows storing blockchain data while ensuring the critical business logic and ledger state are stored on the blockchain.

Conventional cloud-based storage systems are also viable options for data storage in dApps. Additionally, developers may explore decentralized storage alternatives to maintain and enhance the trustless nature of dApps.

Understanding these fundamental components is essential for successful dApp development, enabling developers to build robust and functional decentralized applications.

Essential Dependencies for Decentralized Application Development

In a comprehensive dApp development tutorial, it is important to address the dependencies necessary for creating decentralized applications. Here are the key dependencies commonly required for dApp development:

Node Package Manager (NPM)

NPM is a package manager that comes bundled with JavaScript in the Node.js library. It is essential to ensure that NPM is installed before commencing the development process.

Development Framework (e.g., Truffle)

A dApp development platform such as Truffle or Hardhat is a crucial requirement. For instance, the Truffle framework facilitates the development of Ethereum-based decentralized applications. It provides developers with a suite of tools for creating smart contracts using Solidity. Truffle also assists in testing and deploying smart contracts on blockchain networks, making it an ideal platform for developing the client-side application of a dApp.

Ganache

Ganache is often highlighted in technical guides for dApp development. It is a local in-memory blockchain that can be downloaded from the Truffle framework website. Ganache serves as an essential component for deploying dApps, enabling developers to test their applications in a local blockchain environment.

Metamask

Metamask wallet extension is another crucial dependency for dApp development. It allows for seamless connection to the Ethereum blockchain, providing developers with a user-friendly interface to interact with dApps. Metamask is available as a Google Chrome web extension.

Syntax Highlighting

Since Solidity is the programming language used for blockchain dApp development, it is recommended to have syntax highlighting support. Most integrated development environments (IDEs) and text editors do not include built-in syntax highlighting for Solidity. Therefore, it is important to choose a package or plugin that supports Solidity syntax highlighting to enhance the development experience.

By ensuring these dependencies are in place, developers can create decentralized applications effectively, leveraging the necessary tools and frameworks for successful dApp development.

Step-by-Step Guide for Creating a Decentralized Application

To provide a beginner-friendly approach to dApp development, here is a step-by-step guide for creating a dApp that retrieves and stores ETH prices in a smart contract:

Smart Contract Development

Begin by developing the smart contract. In this example, we will use a simple smart contract that retrieves and stores ETH price information using a data feed from Chainlink, a trusted decentralized Oracle network. Follow these steps:

a. Set up your development environment: Use an IDE like Visual Studio Code and install Hardhat, a popular Ethereum Virtual Machine (EVM) development framework.

b. Create a new directory: Create a new directory for your dApp and include a backend folder to store the smart contract logic.

c. Edit the smart contract: Open the directory in Visual Studio Code, install Hardhat, and remove the “Touch.sol” file from the “contracts” folder. Create a new file called “PriceConsumerV3.sol” in the “contracts” folder.

d. Copy smart contract logic: Copy the sample dApp smart contract logic from the official Chainlink documentation into the “PriceConsumerV3.sol” file. The contract should include a “getLatestPrice” function to retrieve current ETH/USD prices from a data feed.

e. Add storage variable and function: Create a new variable within the “priceFeed” variable to store the ETH price value. Set up a new function that allows the dApp front-end to call and retrieve the latest ETH price using the “getLatestPrice” function and store the result value in the “storedPrice” variable.

Frontend Development

After completing the smart contract development, proceed to develop the frontend of your dApp. This step involves creating a user interface (UI) for users to interact with the smart contract. Here are the recommended steps:

a. Create the frontend directory: Within your dApp directory, create a new directory for the frontend code.

b. Develop the UI: Use familiar web technologies such as HTML, CSS, and JavaScript to create the UI for your dApp. You can utilize libraries like Web3.js or Ethers.js to interact with the smart contract.

c. Connect the UI to the smart contract: Use client-side libraries like Web3.js or Ethers.js to connect the UI with the smart contract. This allows the UI to invoke functions from the smart contract and display the retrieved ETH price.

Testing and Deployment

After completing the development of both the smart contract and the frontend, it’s essential to test and deploy your dApp. Follow these steps:

a. Test the smart contract: Use the testing framework provided by Hardhat or other testing tools to write and execute tests for your smart contract. Ensure that the contract functions as expected and handles various scenarios.

b. Deploy the smart contract: Choose an Ethereum network (such as a testnet or mainnet) and use tools like Hardhat or Truffle to deploy your smart contract onto the chosen network.

c. Host the frontend: Deploy the frontend code on a web server or a hosting platform of your choice. Ensure that it is accessible to users.

Interact with the dApp

Once your dApp is deployed and accessible, users can interact with it through the UI you developed. They can retrieve the latest ETH price and view the stored price within the dApp.

By following these step-by-step instructions, you can create a decentralized application that retrieves and stores ETH prices using a smart contract.

Smart Contract Deployment Steps with Hardhat

After creating your smart contract, it’s essential to follow best practices when deploying it. Here are the steps to deploy your smart contract using the Hardhat development platform:

Install Required Libraries

Ensure that you have the necessary libraries installed for smart contract deployment. This includes the Hardhat library, dotenv library for storing private keys and passwords, and the Chainlink contracts library for utilizing data feeds in your dApp.

Configure “hardhat-config.js”:

Open the “hardhat-config.js” file and add the relevant code for compiling and deploying the smart contract. Customize the configuration based on your requirements, such as network settings and compiler versions.

Configure “.env” File:

Within the backend folder, create a “.env” file and configure it. Extract the private key from your crypto wallet and paste it as the value for the “PRIVATE_KEY” variable in the “.env” file. It is crucial to use a wallet that doesn’t hold funds on the main blockchain network to ensure security.

Obtain RPC Endpoint:

Obtain the RPC endpoint to access the Rinkeby test network. Enter the RPC URL for the “RINKEBY_RPC_URL” variable in the “.env” file. Node providers like Infura can help you obtain the RPC URL.

Modify “deploy.js” File:

Locate the “deploy.js” file within the “scripts” folder and modify its contents. Replace the existing code with your smart contract logic. The code should deploy the compiled “PriceConsumerV3” contract and define the deployment strategies.

Compile and Deploy:

Once you have saved the changes, compile and deploy the smart contract using the Hardhat command-line interface (CLI). Run the appropriate command to compile and deploy your contract, targeting the Rinkeby test network. After successful deployment, you will receive a message displaying the address where the smart contract has been deployed on the Rinkeby test network.

Record the Contract Address:

Take note of the contract address as it is a crucial requirement for the subsequent steps in developing your ETH price tracking dApp. You will need this address to interact with the deployed contract.

By following these steps, you can compile and deploy your smart contract using the Hardhat development platform, ensuring it is deployed on the Rinkeby test network and obtaining the contract address for further development of your ETH price tracking dApp.

Develop dApp Frontend

To develop the frontend of your decentralized application (dApp) using React and Ethers.js, follow these steps:

Set up React Application:

Install and set up the React application using the ‘create-react-app’ boilerplate project. Create a new ‘frontend’ folder and install the necessary dependencies within it. Modify the React application logic according to your dApp requirements.

Install Ethers.js and Bootstrap:

Install the Ethers.js and Bootstrap libraries in your dApp development platform. Ethers.js is essential for connecting smart contracts to the frontend, while Bootstrap provides CSS styling and React-compatible UI widgets.

Modify ‘App.js’:

Access the ‘App.js’ file in your React application and remove the existing contents. Update the code according to your dApp’s needs.

Inform React and Ethers.js Usage:

Inform the dApp that it will use React and Ethers.js by importing them. Create the ‘App’ function and implement the necessary content inside it. Set up the required functionalities such as ‘setStoredPrice’ and ‘storedPrice’ React hooks. Connect the dApp to the desired web3 wallet and specify the smart contract address and ABI.

Create Functions:

Create two functions for the dApp: ‘getStoredPrice’ and ‘setNewPrice’. Invoke the ‘getStoredPrice’ function within the ‘App’ function.

Return JSX Code:

In the final stage, modify the code to render the JSX code on the browser. Add the desired functionalities to the lower section of the ‘App’ function, below the ‘getStoredPrice()’ call. The code should return a basic grid layout with two columns. The first column should display the existing ETH/USD pricing stored in the smart contract, and the second column should contain a button for interacting with the smart contract and updating the stored price.

By following these steps, you can develop the frontend logic and user interface for your decentralized application using React and Ethers.js.

Successful Projects and dApps Developed in the Web3 Ecosystem

Case Study 1: Uniswap V3 – Leveraging Hardhat for Enhanced DEX Functionality

Uniswap, a leading decentralized exchange on Ethereum, utilized the Hardhat development environment to launch its third iteration, Uniswap V3. With advanced debugging and testing features, Hardhat ensured secure and efficient implementation of complex smart contract upgrades. Uniswap V3 now offers concentrated liquidity and flexible fees, solidifying its position as a premier DEX on the Ethereum network.

Case Study 2: Chainlink – Strengthening Oracle Reliability with Hardhat

Chainlink, the top decentralized oracle network, harnessed the power of Hardhat during its development process. By leveraging Hardhat’s powerful tools, Chainlink enhanced the security and reliability of its oracle network, crucial for providing accurate and tamper-proof data to smart contracts. With Hardhat’s support, Chainlink has become the go-to solution for dApps requiring real-world data, including price feeds, random number generation, and event outcomes.

Case Study 3: Aave Protocol – Streamlined Development of DeFi Innovations with Hardhat

Aave, a prominent decentralized lending and borrowing platform, integrated Hardhat into its development process. Capitalizing on Hardhat’s task automation and extensibility features, the Aave team streamlined the development and deployment of their complex smart contracts. As a result, Aave has emerged as one of the largest and most innovative DeFi platforms, offering a range of financial products such as flash loans, credit delegation, and interest rate swaps.

Case Study 4: Yearn Finance – Maximizing Yield Opportunities with Hardhat

Yearn Finance, a decentralized platform focused on yield farming optimization, achieved success with the Hardhat environment. By utilizing Hardhat’s flexible configuration and plugin system, Yearn Finance seamlessly integrated with other tools and frameworks, ensuring an efficient and secure development process. This has enabled Yearn Finance to deliver cutting-edge yield optimization strategies and vaults, attracting DeFi enthusiasts aiming to maximize their returns.