Get started

Installation

Use the published JavaScript client, or skip the dependency and call the HTTPS API directly. Both speak to the same engine and the same project-scoped keys.

Requirements

Node.js 18 or newer (for the JavaScript client).
A ZKAuth project and its API keys. Create one here.

Install the client

The zkauth-client package wraps the zero-knowledge proof handshake so you call register and login like any other API.

bash

npm install zkauth-client# pnpm add zkauth-client# yarn add zkauth-client

Configure your keys

Keys are scoped to a single project. Start with the test key; swap in the live key for production.

.env.localbash

# server-only runtime configZKAuth project key = zka_test_...ZKAuth API base URL = https://api.zkauth.dev

Keep keys server-side

Never ship a key in client-side bundles. For browser-hosted flows, use hosted proxy mode or proxy requests through your own backend. See SDK reference.

Initialize from trusted server code

lib/zkauth.tsts

import { ZKAuthSDK } from 'zkauth-client'
export const zkauth = new ZKAuthSDK({  apiKey: loadServerOnlyProjectKey(),  baseUrl: loadServerOnlyApiBaseUrl(),})

Initialize for hosted browser flows

Use hosted proxy mode when browser code needs to call ZKAuth-hosted routes without receiving a project API key.

browser-auth.tsts

import { ZKAuthSDK } from 'zkauth-client'
export const zkauth = new ZKAuthSDK({  hostedProxy: {    projectSlug: 'your-project-slug',    clientId: 'your_public_client_id',  },})

Without the SDK

Every operation is a plain HTTPS request with an x-api-key header. A quick check that your key works:

bash

API_KEY_HEADER="x-api-key: $ZKAUTH_API_KEY"curl https://api.zkauth.dev/api/v1/client/me \  --header "$API_KEY_HEADER"

See the full contract in the API reference.