Smart contracts & SDKs: Web3 developer tools

Frameworks, client libraries, CLIs and contract libraries for writing, testing and deploying on-chain code.

Foundry

Foundry contributors (foundry-rs)

Best for Fast Solidity build, test and deploy toolkit

Chains: Ethereum Any EVM chain (no specific chain named)
Price: Free (open source)
License: MIT OR Apache-2.0

A Rust toolkit (Forge, Cast, Anvil, Chisel) for compiling, testing, deploying and poking at Solidity contracts, popular for fast tests and fuzzing. Free and open source. Its docs name Ethereum and otherwise work on any EVM chain, so we don't give it chain-specific badges.

Full verdict and sources

Visit Foundry Checked Oct 15, 2026 against this source

Hardhat

Nomic Foundation

Best for Plugin-based TypeScript environment for EVM contracts

Chains: Ethereum Any EVM chain (no specific chain named)
Price: Free (open source)

A plugin-based TypeScript development environment to compile, test, debug and deploy EVM contracts, with a large plugin ecosystem. Free and open source. Its docs name Ethereum mainnet and testnets and otherwise target any EVM chain.

Full verdict and sources

Visit Hardhat Checked Oct 15, 2026 against this source

OpenZeppelin Contracts

OpenZeppelin

Best for Standard Solidity token and access-control contracts

Chains: Ethereum Any EVM chain (no specific chain named)
Price: Free (open source)
License: MIT

The standard library of reusable Solidity contracts: ERC-20, 721 and 1155 tokens, access control and utilities. Free and MIT-licensed. Written for Ethereum and any EVM chain. OpenZeppelin also publishes a separate Soroban library for Stellar.

Full verdict and sources

Visit OpenZeppelin Contracts Checked Oct 15, 2026 against this source

Anchor

Solana Foundation (Anchor maintainers)

Best for The standard framework for Solana programs

Chains: Solana
Price: Free (open source)
License: Apache-2.0

Rust framework and CLI for writing, testing and deploying Solana programs, with generated IDLs and clients. Free and open source; its quickstart names localnet, devnet and mainnet clusters.

Full verdict and sources

Visit Anchor Checked Oct 15, 2026 against this source

AlgoKit

Algorand Foundation

Best for Algorand's official toolchain for contracts and LocalNet

Chains: Algorand
Price: Free (open source)
License: MIT

The Algorand Foundation's CLI and toolchain for scaffolding, building, testing on LocalNet and deploying Algorand smart contracts, with built-in MainNet and TestNet configs. Free and MIT-licensed. Pairs with Puya, the Algorand Python compiler.

Full verdict and sources

Visit AlgoKit Checked Oct 15, 2026 against this source

xrpl.js

XRP Ledger Foundation (XRPLF)

Best for Reference JavaScript library for the XRP Ledger

Chains: XRP Ledger testnet
Price: Free (open source)
License: ISC

The XRPL Foundation's JavaScript and TypeScript library for building, signing and submitting XRP Ledger transactions. Free, ISC-licensed and actively maintained. The README example uses Testnet; the library works with any XRPL network.

Full verdict and sources

Visit xrpl.js Checked Oct 15, 2026 against this source

Stellar JS SDK

Stellar Development Foundation

Best for Official SDK for Horizon, Stellar RPC and Soroban contracts

Chains: Stellar
Price: Free (open source)
License: Apache-2.0

The Stellar Development Foundation's JavaScript and TypeScript SDK for Horizon, Stellar RPC and Soroban contract clients. Free and Apache-2.0; its README names Mainnet, Testnet and Futurenet.

Full verdict and sources

Visit Stellar JS SDK Checked Oct 15, 2026 against this source

Hiero SDK JS

Hiero (LF Decentralized Trust) / Hashgraph

Best for Official SDK for Hedera accounts, tokens, consensus and contracts

Chains: Hedera
Price: Free (open source)
License: Apache-2.0

The official JavaScript and TypeScript SDK for Hedera's native services: accounts, HTS tokens, the consensus service and smart contracts. Free, Apache-2.0 and released frequently. Java, Go, Python and Rust SDKs also exist.

Full verdict and sources

Visit Hiero SDK JS Checked Oct 15, 2026 against this source

xahau.js

Xahau (XRPL Labs / Xahau contributors)

Best for Official JavaScript library for Xahau

Chains: Xahau
Price: Free (open source)
License: ISC

The official JavaScript and TypeScript client library for Xahau, a fork of xrpl.js, published on npm as 'xahau'. Free and actively maintained. The quickstart uses testnet; Xahau's docs list the public mainnet endpoints.

Full verdict and sources

Visit xahau.js Checked Oct 15, 2026 against this source

Hooks Toolkit

Transia (Transia-RnD) / Xahau

Best for Scaffold, compile and test Xahau Hooks

Chains: Xahau testnet
Price: Free (open source)
License: GPL-3.0-or-later (toolkit); MIT (@xahau/hooks-cli)

TypeScript SDK and CLI for scaffolding, compiling, setting and testing Xahau Hooks smart contracts. Free and open source (the toolkit is GPL-3.0, the CLI MIT). The docs only show a testnet configuration, so we list it as testnet.

Full verdict and sources

Visit Hooks Toolkit Checked Oct 15, 2026 against this source

Evernode JS Client

Evernode Labs

Best for Work with Evernode hosts and leases from your own app

Chains: Xahau
Price: Free on npm
License: custom (evernode-license.pdf in repo)

Evernode's JavaScript library for working with hosts, leases, tokens and Xahau transactions from your own application. Free on npm under Evernode's own license. We couldn't see a recent commit date when we checked, so confirm it's current before you depend on it.

Full verdict and sources

Visit Evernode JS Client Checked Oct 15, 2026 against this source

One short email when we add tools or a tool adds, drops or deprecates a chain. Nothing new, no email. Unsubscribe anytime.

Smart contracts & SDKs: Web3 developer tools

Know when chain support changes