explaingit

slvdev/sigby

Analysis updated 2026-05-18

★ 0TypeScriptAudience · developerComplexity · 4/5Setup · moderate

TLDR

A Chrome wallet extension that lets you sign crypto transactions with a passkey instead of a seed phrase, using smart accounts for the same address across chains.

Mindmap

mindmap
  root((Sigby))
    What it does
      Passkey signing
      Smart accounts
      Same address per chain
    Tech stack
      TypeScript
      Porto
      WebAuthn
    Use cases
      Self custodial wallet
      Pay gas in stablecoins
      Connect to dApps
    Audience
      Crypto users
      Developers

Code map

Detail Auto

An interactive map of this repo's files and how they connect — its source is parsed live in your browser. Click Visualize to build it.

filefunction / class

What do people build with it?

USE CASE 1

Create a self-custodial crypto wallet secured by Face ID, Touch ID, or Windows Hello instead of a seed phrase.

USE CASE 2

Pay gas fees in USDC or USDT instead of a chain's native token.

USE CASE 3

Use the same wallet address across Ethereum, Base, Arbitrum, Optimism, and Polygon.

What is it built with?

TypeScriptPortoWebAuthnEIP-7702

How does it compare?

slvdev/sigby0xradioac7iv/tempfsabboskhonov/hermium
Stars000
LanguageTypeScriptTypeScriptTypeScript
Setup difficultymoderatemoderatemoderate
Complexity4/53/54/5
Audiencedeveloperdeveloperdeveloper

Figures from each repo's GitHub metadata at analysis time.

How do you get it running?

Difficulty · moderate Time to first run · 30min

Requires pnpm, a build step, and loading the extension unpacked in Chrome developer mode.

In plain English

Sigby is a Chrome browser extension wallet for crypto applications on the web. Its main feature is signing with a passkey, the same biometric authentication built into your device such as Touch ID, Face ID, or Windows Hello, instead of the twelve word seed phrase most crypto wallets require. There is nothing to write down. The passkey is hardware backed and syncs automatically through iCloud, Google Password Manager, or a similar platform keychain. Under the hood, Sigby uses EIP-7702 smart accounts, which means your wallet address behaves like a smart contract during a transaction. This allows batching several actions together atomically, so approving and swapping tokens can happen in one step instead of two separate popups, and it allows paying transaction fees in USDC or USDT instead of only the chain's native token. Your wallet address is also the same across every supported chain, including Ethereum, Base, Arbitrum, Optimism, and Polygon, so you do not end up with different addresses on different networks. Every signing operation still triggers a fresh biometric prompt, since the passkey keys are hardware backed by the device's Secure Enclave or TPM chip, making them resistant to phishing. The wallet supports multiple accounts, each with its own passkey and its own connections and history, and it keeps a separate chain selection per website so different dApps on different networks do not interfere with each other. The extension can also grant a dApp a limited, time bound signing permission called a session key, though the README notes that today every signing request still opens an approval popup regardless, so the promise of skipping repeated popups is a planned improvement rather than something that works yet. Sigby is built on Porto, a library from the Ithaca team, and is written in TypeScript. It is currently in alpha, connects to any decentralized application using the EIP-1193 or EIP-6963 standards, and the README explicitly warns against storing meaningful funds in it before a stable release. The full README is longer than what was shown.

Copy-paste prompts

Prompt 1
Explain how smart accounts let this wallet share one address across chains.
Prompt 2
Walk me through building and loading this Sigby extension as an unpacked Chrome extension.
Prompt 3
Help me understand how passkey-based signing replaces seed phrases in this wallet.
Prompt 4
Show me how session keys are supposed to work in this codebase once fully implemented.

Frequently asked questions

What is sigby?

A Chrome wallet extension that lets you sign crypto transactions with a passkey instead of a seed phrase, using smart accounts for the same address across chains.

What language is sigby written in?

Mainly TypeScript. The stack also includes TypeScript, Porto, WebAuthn.

How hard is sigby to set up?

Setup difficulty is rated moderate, with roughly 30min to a first successful run.

Who is sigby for?

Mainly developer.

Open on GitHub → Explain another repo

This repo across BitVibe Labs

Verify against the repo before relying on details.

Alternatives & similar repos