Web3Signer

noble cryptography is a family of minimal-dependency TypeScript cryptographic libraries that prioritize readable source, signed releases, and transparent npm builds, and they underpin most modern JavaScript wallets including MetaMask, Rabby, Rainbow, and many SDKs across the ecosystem.

Trezor Connect is a JavaScript SDK for integrating Trezor hardware wallet signing, including Ethereum, into applications and wallets. Builders use it when users should sign with a Trezor device.

blst is a multilingual BLS12-381 signature library and the BLS implementation behind most Ethereum consensus clients. Builders link against it in Rust, C, or Go when writing validator or consensus tooling.

The Ledger hw-app-eth package is the JavaScript API for signing Ethereum transactions and messages with a Ledger device, and it sits behind the Ledger connectors in wagmi and viem. Wallet and application builders import it to add hardware wallet signing.

py_ecc is a Python library for elliptic curve pairing operations over bn128 and BLS12-381, used by py-evm and other Python tooling. Builders import it for precompile or BLS work in Python.

eth-crypto is a set of JavaScript helpers for signing, verifying, recovering addresses, and ECIES encryption alongside ethers or web3. Builders import it for one-off cryptographic steps that the client libraries do not expose directly.