Primer Pay lets you put any post or page behind a micropayment wall using the x402 protocol. Visitors with the Primer Pay browser extension pay seamlessly and see your content instantly. No user accounts, no subscriptions, no payment forms.

How it works:

You enter your wallet address in Settings > Primer Pay.
You check “Enable x402 Paywall” on any post and set a price (e.g., $0.01 USDC).
Visitors with the Primer Pay Chrome extension pay automatically and see your content.
Visitors without the extension see a teaser and a prompt to install Primer Pay.
Payments settle on Base (Ethereum L2) via USDC — low fees, instant finality.

Features:

Gutenberg Content Gate block — visual divider between free teaser and paid content with inline settings
Classic editor support — [primer_pay_x402] shortcode plus sidebar meta box
Per-post price override (defaults to your site-wide price)
Per-post wallet override — route payments to a different wallet per post (multi-author support)
Multi-network: accept payments on Base, SKALE Base, or both — with configurable priority
Theme-matching paywall banner — inherits your site’s fonts, colors, and border radius
Configurable access duration: 30 minutes to “never expires”
.well-known/x402 discovery endpoint — JSON index for AI agents and crawlers to find purchasable content
Works with any theme that renders the_content() normally
No user accounts or login required
Non-custodial — payments go directly to your wallet

Requirements:

A wallet address on Base or SKALE Base (e.g., from MetaMask, Coinbase Wallet, or Primer Pay itself — same address works on all supported networks)
HTTPS recommended (cookies are marked Secure on HTTPS; HTTP still works for local dev)

External services

This plugin relies on the Primer x402 facilitator service to verify and settle payments. When a visitor attempts to pay for content, the plugin sends the signed payment authorization to the facilitator, which validates the signature and executes the on-chain USDC transfer on the Base network.

Service: Primer x402 Facilitator
Endpoint: https://x402.primer.systems/settle
When: Whenever a visitor submits a valid X-PAYMENT header to the plugin’s unlock endpoint
Data sent: The base64-encoded signed payment authorization (EIP-712 typed data) from the visitor, plus the payment requirements (amount, asset address, recipient wallet address, network). No personally identifiable information about the visitor is sent — the only identifier is the wallet address they signed with.
Terms of service: https://primer.systems
Privacy policy: https://primer.systems

This is the standard x402 protocol flow. If you prefer to run your own facilitator, you can configure a custom facilitator URL in the plugin settings.