General
What is Vanta SDK?
Vanta SDK is a toolkit for implementing HTTP 402 (Payment Required) flows using blockchain payments.
What networks are supported?
Base, Ethereum, Optimism, Arbitrum, and Polygon.
Do I need my own smart contracts?
No. Vanta uses native ETH transfers with embedded payment data. No contracts needed.
Pricing
How much does Vanta SDK cost?
The SDK is open source and free. You only pay network gas fees for transactions.
What's the minimum payment amount?
As low as you want. On Base, micropayments of $0.01 or less are economical.
Security
How are payments verified?
Payments are verified on-chain by checking transaction existence, amount, recipient, and data.
Can payments be replayed?
No. Each payment challenge is single-use and time-limited.
Integration
What frameworks are supported?
Express, Next.js, Fastify, Hono, Cloudflare Workers, and any Node.js or edge runtime.
Is there a Python SDK?
Yes, see the FastAPI recipe for Python integration.