Overview
Mesh is a free code toolkit that lets web developers build blockchain apps: apps that send payments, mint tokens, and connect to people's crypto wallets. It is an SDK (software development kit, a ready-made set of code building blocks) written in TypeScript, a typed version of JavaScript1. Mesh handles the fiddly accounting behind each transaction, such as picking which coins to spend and working out the fee1.
Mesh's transaction builder, wallet connectors, and contract library target Cardano1. On Midnight, a privacy-focused network that works alongside Cardano, Mesh adds a setup package that connects a wallet and deploys smart contracts (programs that run on a blockchain), plus a wizard that starts contract projects from templates2. On Bitcoin, Mesh connects to browser wallets such as Xverse and runs a self-custody wallet that needs no browser extension3. A community of builders maintains Mesh, and its company, MeshJS Pte. Ltd., has been registered in Singapore since 20234.
Key Features
- Transactions without the bookkeeping. Mesh's transaction builder lets a developer list what a transaction should do, such as token minting, staking, smart contracts, and Cardano governance actions5.
- Wallet connections for websites and servers. Mesh links apps to Cardano browser wallets such as Eternl and Lace through CIP-30, the standard those wallets use to talk to websites6. A server-side wallet signs for minting scripts and automated jobs7.
- Pay-per-use payments in ADA or other Cardano tokens. Mesh's x402 package, built on the x402 open web-payments standard, lets a site charge for a page or a data request. The server names a price, the visitor's app pays, and the content unlocks, with no accounts or checkout page8.
- Escrow for AI agent jobs. With the method from Masumi, a payment network for AI agents, an x402 payment is locked in its escrow contract instead of going straight to the seller. The seller collects after delivering, the buyer can ask for a refund, and admins settle disputes9.
- Interchangeable data sources. Apps read blockchain data through providers, services that report what is on the chain, such as Blockfrost, Koios, Nexus, Ogmios, and UTxO RPC, plus Blockstream for Bitcoin. Mesh's Cardano providers follow shared interfaces, so an app can swap one for another that does the same job10.
What to Expect
Developers comparing transaction builders will find that Mesh describes itself as a kit for whole apps, not only transactions. Its comparison guide sets Mesh against Lucid, another TypeScript library, and lists official packages for React and Svelte, two popular tools for building web pages11. Teams moving off Lucid get a step-by-step migration guide that maps Lucid code to Mesh equivalents12.
Mesh also ships starter smart contracts for escrow, vesting, a marketplace, and token swaps, written in Aiken, a Cardano smart contract language13. A single terminal command sets up a new project1. Developers who code with AI assistants get agent skills for tools like Claude Code and Cursor, a chatbot that answers from the docs, and an MCP server, a plug-in that brings Mesh docs into editors such as VS Code14.
Mesh is a developer tool, so people who don't write code meet it only through apps built on it. The Mesh team also runs Mesh Multisig Wallet, a separate app for shared wallets that need several people to sign.
Mesh's code is open source under the Apache 2.0 license1. Project Catalyst, Cardano's community-voted grant program, has paid for its upkeep, including a Fund 10 grant for library development and developer resources15. Intersect, the member organization that coordinates Cardano development, has featured MeshJS as one of its enterprise members16.
