Plaid
Plaid Technical Briefing
Published November 15, 2022
Supported by Modern Treasury , IowaEDA and Brale
Overview
Plaid introduces Wallet Onboard — a Plaid product for crypto developers that brings the familiar Plaid "connect" experience to self-custody crypto wallets. Where Plaid has always linked bank accounts to fintechs, Wallet Onboard normalizes the fragmentation across hundreds of crypto wallets, multiple connection protocols, and the UX differences between MetaMask, Coinbase Wallet, Rainbow, Ledger, and WalletConnect-compatible wallets. The demo shows auto-detection of installed extensions, per-wallet optimized flows (QR for mobile-only wallets, desktop app handoff for hardware), direct wallet-to-app data flow with no Plaid intermediary on wallet addresses, and a drop-in vanilla JavaScript SDK that takes roughly an hour to integrate — plus auto-updates for new wallets and protocols delivered via cdn.plaid.com. Use cases span token gating, NFT mint, holdings tracking, payouts, and message-signature-based authentication.
0:00 Introduction to Plaid — from bank connect to crypto
Plaid traditionally links bank accounts to fintech apps — Venmo, Robinhood, and thousands of others. With crypto exchanges and self-custody tools emerging as major Plaid customers, the team looked at what a Plaid-native primitive for crypto developers would look like.
1:00 Parallels between banks and crypto wallets
Just as there are thousands of financial institutions, there are hundreds of different crypto wallets, many protocols, and lots of normalization and UX work — all problems Plaid has already solved once for banking.
1:30 Wallet Onboard — Plaid for self-custody crypto wallets
Plaid announced Wallet Onboard, a product that helps crypto developers connect self-custody wallets with the same familiar Plaid feel — no wallet addresses collected, no intermediary sitting between the app and the wallet.
2:30 Per-wallet optimized connection flows
Wallet Onboard detects if MetaMask is installed locally, shows a QR scan for MetaMask mobile, jumps straight to a QR code for mobile-only wallets like Rainbow, and hands off to a desktop app for hardware wallets like Ledger.
4:00 Wallet data straight from the wallet — no Plaid intermediary
Once connected, address, chain, and balance data come directly from the wallet over an in-browser connection. Plaid is not in the data path; apps can request transaction signatures, mint NFTs, or token-gate using the wallet address directly.
5:00 Pain of rolling your own wallet connect
Live code comparison: the window.ethereum approach handles only browser-extension wallets, leaves you to manage chain IDs and hex-vs-decimal quirks, and doesn't work for mobile, Coinbase Wallet, or WalletConnect. Plaid's SDK smooths over all of it.
6:00 Drop-in JavaScript SDK
Wallet Onboard is a vanilla JS script tag — no React required. Drop it in, configure chain and RPC URL, pass callbacks, and call open() to launch the flow. A checkForExistingConnection() API lets apps rehydrate connections silently.
7:30 Auto-updates as new wallets come online
Because the SDK is served from cdn.plaid.com, Wallet Onboard auto-updates whenever a new wallet ships — Trust Wallet's new extension, new mobile protocols, new conversion optimizations — without app bumps.
8:30 Use cases: token gating, NFT mint, payouts, auth
Production use cases seen on Wallet Onboard: token gating (Clubhouse), NFT minting, holdings tracking for finance-management apps, payout address capture, and wallet-backed user authentication via message signatures.
Presented by Clay Allsopp — Plaid · LinkedIn · website
Topics: Open Banking, Identity & KYC, Developer Tools
