OpenWallet

A non-custodial, multi-chain browser wallet — one seed, one signing model, across EVM, Solana and Bitcoin.

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OpenWallet is a browser-extension wallet built in the open: a BIP-39 seed, SLIP-0010/BIP-32 derivation, an encrypted-at-rest vault, and per-chain signing behind a single ChainAdapter contract, so EVM, Solana and Bitcoin are driven by exactly the same send flow. Keys never leave the extension's background worker — dApps talk to it over EIP-1193/EIP-6963, and price, token and swap data comes from a stateless API that never sees a key. Every primitive either wraps an audited library (@noble/*, @scure/*, viem, bitcoinjs-lib, @solana/web3.js) or, where implemented here (SLIP-0010 derivation), is verified against the official spec test vectors. See docs/architecture.md for the security invariants and how to add a chain.

Built with

Area	Technology
Language	TypeScript (Node.js ≥ 20, strict, type-aware ESLint)
Extension	WXT + React 19, Tailwind CSS 4, Radix UI
Cryptography	@noble/* / @scure/*
EVM	viem — signing, ERC-20, fee tiers, ENS
Solana	@solana/web3.js — SPL, priority fees
Bitcoin	bitcoinjs-lib — native SegWit, PSBT, RBF
Swaps	LI.FI (EVM) and Jupiter (Solana)
Backend	NestJS 11 with Zod request/response contracts
Tooling	pnpm workspaces, Vitest, Prettier, Knip

How it works

flowchart LR
    A[BIP-39 mnemonic] --> B[SLIP-0010 / BIP-32 derivation]
    B --> C[Encrypted vault]
    C --> D{ChainAdapter}
    D --> E[EVM]
    D --> F[Solana]
    D --> G[Bitcoin]
    H[dApp] -->|EIP-1193 / EIP-6963| D
    D --> I[JSON-RPC nodes]
    J[OpenWallet API] -->|prices, tokens, swap quotes| D

Loading

1. A mnemonic is generated or imported, then encrypted into a vault that only decrypts with the user's password — the plaintext seed never touches disk.
2. Accounts are derived per chain from that one seed (secp256k1 for EVM and Bitcoin, ed25519 for Solana), each following its chain's SLIP-44 path convention.
3. Every chain package exposes the same ChainAdapter: derive, validate, quote fees, build, sign, broadcast. The UI and the dApp bridge only ever talk to that interface, so adding a chain doesn't touch the send flow.
4. Signing happens in the extension's background worker behind an auto-lock; the injected page provider relays requests but never holds key material.

Workspace

Package	What it is
@openwallet/core	Mnemonic, HD/SLIP-10 derivation, encrypted vault, keyring, ChainAdapter
@openwallet/chain-evm	EVM derivation, signing, ERC-20 transfers, fee tiers, ENS, speed-up/cancel
@openwallet/chain-solana	Solana derivation, signing, SPL transfers, fee tiers
@openwallet/chain-bitcoin	Bitcoin (native SegWit) derivation, PSBT signing, RBF, message signing
@openwallet/api-contract	Zod schemas shared by the API and its consumers
@openwallet/lifi-client	LI.FI quotes and token lists for EVM swaps
@openwallet/jupiter-client	Jupiter quotes and token lists for Solana swaps
@openwallet/extension	The browser extension: onboarding, accounts, send, swap, dApp approvals
@openwallet/api	NestJS service for prices, tokens and swap routing — stateless, key-free

Dependency direction is chain-* → core only. core never imports a chain package and chain packages never import each other; ESLint enforces it rather than leaving it to convention.

Getting started

Prerequisites: Node.js ≥ 20 and pnpm 10.

pnpm install
pnpm build       # compile every package
pnpm test        # vitest across the workspace
pnpm check       # format + build + lint + typecheck + knip + test

Run the extension in watch mode — WXT opens a browser with it loaded; build instead emits apps/extension/.output/chrome-mv3 to load unpacked yourself:

pnpm --filter @openwallet/extension dev
pnpm --filter @openwallet/extension build

Run the API alongside it:

pnpm --filter @openwallet/api dev

Contributions are welcome — see CONTRIBUTING.md.

License

MIT © RedDuck Limited