What programming languages are used for smart contracts?

Understanding Smart Contracts and Their Execution Environment

Smart contracts are self-executing programs deployed on blockchain networks that automatically enforce the terms of an agreement when predefined conditions are met. These contracts run on decentralized platforms such as Ethereum, Binance Smart Chain, and Solana, and are immutable once deployed. The execution environment for smart contracts is typically a virtual machine—like the Ethereum Virtual Machine (EVM) or Solana’s Sealevel runtime—which interprets and executes the compiled bytecode of the contract. Because these environments are isolated and deterministic, the programming languages used must produce predictable, secure, and verifiable code. This requirement shapes the design and adoption of specific languages tailored to blockchain development.

Ethereum and the Dominance of Solidity

The most widely used language for writing smart contracts is Solidity, primarily due to its deep integration with the Ethereum network. Solidity is a statically-typed, high-level language influenced by C++, Python, and JavaScript, making it accessible to developers with traditional programming backgrounds. It supports features such as inheritance, libraries, and complex user-defined types, enabling developers to build sophisticated decentralized applications (dApps). Contracts written in Solidity are compiled into EVM bytecode and deployed on the blockchain. To write and test Solidity code, developers commonly use tools like Remix IDE, Hardhat, and Truffle.

• Install Node.js and npm to set up a local development environment
• Use npm install -g hardhat to install Hardhat globally
• Initialize a project with npx hardhat and select “Create a basic sample project”
• Write a contract in a .sol file inside the contracts/ directory
• Compile the contract using npx hardhat compile
• Write deployment scripts in the scripts/ folder
• Deploy using npx hardhat run scripts/deploy.js --network goerli for testnet deployment

Solidity also supports events, modifiers, and error handling through require, revert, and assert, which are essential for security and debugging.

Vyper: A Simpler, Safer Alternative on Ethereum

Another language targeting the EVM is Vyper, designed with a focus on security, simplicity, and auditability. Unlike Solidity, Vyper intentionally omits certain complex features such as inheritance, function overloading, and recursive calling, reducing the attack surface and making code easier to verify. Vyper’s syntax resembles Python, which enhances readability and lowers the learning curve for new developers. It is particularly favored in projects where code transparency and minimalism are prioritized, such as decentralized finance (DeFi) protocols that require high trust.

• Write a Vyper contract using .vy file extension
• Use the Vyper compiler (vyper contract.vy) to generate bytecode
• Deploy via web3.py or integrate with Brownie, a Python-based development framework
• Test contracts using Brownie’s built-in testing suite
• Verify the deployed contract on Etherscan using the Vyper verification tool

Vyper compiles directly to EVM bytecode and is fully compatible with Ethereum’s tooling ecosystem, though its community and library support are smaller than Solidity’s.

Move: A Language Built for Safety and Resource Management

Developed by the team behind Diem (formerly Libra), Move is a language designed from the ground up for digital asset management and safe smart contract execution. It is now used on blockchains like Aptos and Sui, where it enforces strict rules around resource ownership and linear types, preventing common vulnerabilities such as reentrancy attacks and double-spending. Move’s type system ensures that digital assets cannot be copied or implicitly destroyed, only moved between accounts.

• Define a resource type using the struct keyword with the key or store ability
• Write modules that encapsulate logic and data
• Use Move CLI to initialize a project: move init --name MyProject
• Compile with move build and test with move test
• Deploy modules using the Aptos CLI: aptos move publish --named-addresses my_addr=default

Move’s emphasis on formal verification and memory safety makes it a strong candidate for high-assurance financial applications.

Solana’s Use of Rust and C

On the Solana blockchain, smart contracts—referred to as programs—are primarily written in Rust, with support for C and C++. Solana’s architecture requires programs to be stateless and execute in a high-performance runtime (Sealevel), making low-level control and efficiency critical. Rust is favored due to its memory safety, zero-cost abstractions, and concurrency features, which align well with Solana’s need for speed and security.

• Install the Solana Tool Suite with sh -c '$(curl -sSfL https://release.solana.com/stable/install)'
• Set the CLI to devnet: solana config set --url https://api.devnet.solana.com
• Create a new Rust project using cargo init my_program
• Add solana-program as a dependency in Cargo.toml
• Implement the program logic in lib.rs, ensuring it conforms to Solana’s program entry point (process_instruction)
• Build with cargo build-bpf
• Deploy using solana program deploy ./target/deploy/my_program.so

Developers must also manage on-chain accounts explicitly and handle instruction serialization using Borsh or Bincode.

Other Languages and Emerging Options

Beyond the major platforms, several other languages are gaining traction. Cadence, used on the Flow blockchain, combines resource-oriented programming with static typing and built-in pre/post conditions, enabling safer smart contract development. It uses a syntax similar to Swift and supports type safety and access control natively. Michelson, the low-level language for Tezos, is stack-based and designed for formal verification, though it has a steep learning curve. High-level languages like LIGO and SmartPy compile to Michelson, offering more developer-friendly alternatives.

• In LIGO, write contracts using CamelLIGO (OCaml-like) or PascalLIGO syntax
• Compile to Michelson with ligo compile-contract my_contract.ligo main
• Use Flextesa or Tezos Client to originate (deploy) the contract
• Interact via Taquito or Better Call Dev

Each language reflects the design philosophy of its underlying blockchain, balancing developer experience, security, and performance.

Frequently Asked Questions

Can I use JavaScript to write smart contracts directly on Ethereum?No, JavaScript cannot be used to write smart contracts directly because the Ethereum Virtual Machine does not execute JavaScript. However, JavaScript is widely used in frontend dApp development and scripting deployment tasks via tools like Hardhat and ethers.js. Smart contracts themselves must be written in EVM-compatible languages such as Solidity or Vyper.

Is Rust the only language supported on Solana?While Rust is the most commonly used language for Solana programs, C and C++ are also supported through the BPF (Berkeley Packet Filter) toolchain. Developers can write Solana programs in C, compile them to BPF bytecode, and deploy them. However, Rust offers better tooling, safety guarantees, and community support.

What makes Move different from Solidity in terms of asset handling?Move treats digital assets as linear types, meaning they cannot be copied or deleted accidentally. In Solidity, tokens are represented as numbers in a mapping, which can be vulnerable to bugs. Move’s resource-oriented model ensures assets are moved explicitly between accounts, preventing common errors like double-spending.

Do I need to learn multiple languages to develop across blockchains?Yes, because each blockchain platform uses different execution environments and languages. For example, Ethereum uses Solidity/Vyper, Solana uses Rust, and Flow uses Cadence. While concepts like state management and transaction handling are transferable, the syntax, tooling, and security models differ significantly across ecosystems.