Developers who master the Solidity programming language can earn $105,000 annually on average. And demand for their expertise is growing. Let’s find out why.
Programmers use Solidity specifically for writing Ethereum smart contracts. Smart contracts are self-executing programs that define and enforce the rules and behaviors of accounts within blockchains.
Since its introduction, it has become the default for smart contract development. Solidity is the standard on most EVM-compatible blockchain networks, including Ethereum, Avalanche, Polygon, and Binance Smart Chain.
In this article, we'll explore Solidity, its background, and how it works. We'll also look at its various frameworks and available learning resources to help you become a Solidity developer.
Solidity is a statically-typed, high-level programming language. Its design enables writing and deploying smart contracts on the Ethereum Virtual Machine (EVM). However, it also works on other compatible blockchain platforms.
Solidity is essential for developers building decentralized applications (dApps) that require secure and transparent operations.
Solidity is a Turing-complete language. This means it can simulate any logical step of problem-solving, allowing it to represent and execute any algorithm. It allows developers to create complex logic and functionalities within smart contracts.
Solidity balances ease of use with powerful capabilities, such as:
Solidity’s syntax and features are inspired by existing languages, making it accessible for developers:
if, for, and while loops, from Javascript.
But how did it all start?
Gavin Wood, Ethereum's co-founder, introduced Solidity in 2014. Then, several other core contributors led by Christian Reitwiessner developed the language further.
Solidity is now an open-source, community-driven project governed by the Ethereum Foundation. As such, it evolves with regular updates that introduce new features and improvements.
The language has undergone much development since its introduction. Ongoing improvements introduce new and innovative features.
2014: Gavin Wood and Christian Reitwiessner developed Solidity as a smart contract programming language for Ethereum.
2015: Solidity's first stable release coincided with the launch of the Ethereum mainnet.
2016-17: Rapid adoption by developers. Tools like Remix made smart contract development more accessible and efficient.
2018-Present: Continuous updates and enhancements, including security improvements and optimization features. Solidity integrated new capabilities through Ethereum Improvement Proposals (EIPs), allowing the community to propose and implement changes.
Hardhat, the comprehensive development environment, also launched during this time. It streamlines smart contract building and testing on Solidity.
More recently, the introduction of Foundry offered a fast and efficient framework for developing and testing smart contracts.
So, let’s now explore how it works.
Developers write smart contracts in Solidity using its specific syntax to define contract logic, state variables, and function.
The Solidity Compiler generates two outputs:
The EVM is the runtime environment for smart contracts. It executes the compiled bytecode and manages its state on these networks. This ensures transaction processing and the correct execution of contract logic.
Now that we know how it works, let’s explore Solidity’s real-world use.
Solidity enables developers to create functionality and dApps for an infinite number of use cases, including:
Having covered Solidity’s far-reaching impact across fields, let’s now explore the networks that support it.
While Solidity was initially developed for Ethereum, its popularity and versatility have led to its adoption by several other blockchain networks. These blockchains support Solidity, allowing developers to write and deploy smart contracts across multiple platforms:
ZKsync is an Ethereum Layer 2 scaling solution using zero-knowledge proofs to provide fast, low-cost transactions.
Arbitrum is an optimistic rollup that supports EVM-compatible smart contracts. It enhances Ethereum’s performance by enabling faster and cheaper transactions while maintaining security.
Optimism is also an optimistic rollup for Ethereum that uses fraud proofs to increase transaction throughput and reduce costs.
Let’s get more practical now.
The following frameworks and tools allow Solidity developers to build, test, and deploy smart contracts safely and efficiently:
Remix is a browser-based Integrated Development Environment (IDE) that requires little setup and is readily available for anyone interested in implementing smart contracts. It’s the starting point for many new Solidity developers.
Remix includes various development tools, including a workspace, compiler, and debugger. Its configuration can allow deployment to most major remote procedure call (RPC) services.
Besides the online version, Remix offers a desktop IDE and a Visual Studio Code plugin. These provide extra functionality and more secure local life storage.
Hardhat, is a JavaScript-based framework for managing and automating smart contract development.
It comes with compiling, deploying, testing, and debugging tools. And includes a local Ethereum network for testing, and supports a wide range of plugins.
Hardhat boasts numerous open-source plugins. These include gas analyzers, unit test coverage reports, and tools for integrating front-end applications.
Foundry is a rapidly growing framework known for its speed and extensive toolset.
It simplifies and accelerates smart contract development, testing, and deployment. It also helps developers manage the entire Solidity smart contract development lifecycle. Its fast compilation and testing times compared to other frameworks is also noteworthy.
Foundry components
Foundry also integrates with Layer 2 solutions and EVM chains beyond Ethereum, like Starknet. This enables developers to deploy and test smart contracts with faster, cheaper transactions and enhanced scalability.
If you’re new to Foundry and want to learn, start with Cyfrin Updraft’s Foundry Fundamentals course. If you’re more experienced, you can jump straight into Advanced Foundry.
OpenZeppelin is a library that provides smart contracts for standards like ERC-20 and ERC-721. It also features tools for upgrading smart contracts.
Cyfrin Aderyn is a rust-based Solidity smart contract static analyzer. It helps protocol engineers and security researchers find vulnerabilities in Solidity code.
The Solidity VSCode extension adds support for Solidity to Visual Studio. It includes syntax highlighting, code completion, and inline compilation. These make it easier for developers to write and manage Solidity contracts within the popular IDE.
Beyond the essentials, additional tools are used for deploying and managing smart contracts.
Faucets provide free testnet ETH or other tokens. This enables developers to deploy and interact with smart contracts on test networks without using real funds. The Sepolia Faucet is a popular option used in the Ethereum ecosystem.
Node providers like Infura, Alchemy, and QuickNode offer scalable infrastructure for interacting with blockchains. These services provide quick access to blockchain networks, enabling developers to deploy contracts, read data, and send transactions.
Ankr’s distributed network is a decentralized alternative, providing similar functionality with added robustness and independence from centralized control.
And now, it’s time to dive even deeper with an example.
This contract allows the creator to mint new tokens and users to send tokens to each other.
Note: a simplified example; do not use it in production.
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.26;
contract Coin {
// The keyword "public" makes variables accessible from other contracts
address public minter;
mapping(address => uint) public balances;
// Events allow clients to react to specific contract state changes
event Sent(address from, address to, uint amount);
// Errors allow you to provide information about why an operation failed
error InsufficientBalance(uint requested, uint available);
// Constructor code is only run when the contract is created
constructor() {
minter = msg.sender;
}
// Sends an amount of newly created coins to an address
// Can only be called by the contract creator
function mint(address receiver, uint amount) public {
require(msg.sender == minter);
balances[receiver] += amount;
}
// Sends an amount of existing coins from any caller to an address
function send(address receiver, uint amount) public {
if (amount > balances[msg.sender])
revert InsufficientBalance({
requested: amount,
available: balances[msg.sender]
});
balances[msg.sender] -= amount;
balances[receiver] += amount;
emit Sent(msg.sender, receiver, amount);
}
}
Sent event logs the details of coin transfers.mint allows the minter to create new tokens and update the balance of a specific address.InsufficientBalance error handles cases where a user tries to send more tokens than they have.send enables users to transfer tokens to another address, provided they have sufficient balance.mint function.send function, which triggers the Sent event to log the transaction.Now that you’ve seen an example of a smart contract on Solidity, let’s examine how to secure it.
Smart contracts are immutable. This increases trust but also makes them vulnerable to permanent losses or attacks if bugs or vulnerabilities exist.
For example, the DAO vulnerability in 2016 led to a hard fork in the Ethereum blockchain. Ensuring the security and correctness of smart contracts through code audits is crucial before deployment. Here are a few considerations and options:
Private audits are ideal for projects that need detailed analysis. Competitive audits offer diverse input and faster, cost-effective results. Combining both ensures comprehensive security.
With theoretical basics covered, let’s see how developers can learn Solidity.
Anyone interested in developing dApps and smart contracts on EVM-compatible blockchains must learn Solidity. Here are the top resources to get started:
Cyfrin Updraft offers free comprehensive courses that cover all aspects of smart contract development and security. Its curriculum progresses from foundational topics like Solidity Smart Contract Development to intermediate skills such as Foundry, Assembly, and Formal Verification. Advanced modules focus on Smart Contract Security, DevOps, and DeFi platforms such as Curve and Uniswap.
Solidity by Example is a collection of concise, easy-to-understand code examples. It’s ideal for developers who prefer working with code snippets and seeing practical implementations.
CryptoZombies is a gamified guide with step-by-step instructions and practical coding exercises to help you learn Solidity.
The official Solidity documentation has in-depth explanations of syntax and common patterns. It uses comprehensive reference material and examples.
Ethereum’s official website offers tools, tutorials, documentation, developer resources, and community support.
Learning to code in Solidity is an essential skill for blockchain developers. As the blockchain ecosystems that use it grow, so does the demand for Solidity developers.
To enhance your Solidity skills, jump into Cyfrin Updraft’s free courses. These will kickstart your career in blockchain development.
