Webround x PayPal — Cloudflare Worker

A Cloudflare Worker that adds a standalone PayPal checkout flow to a Webround store, without Stripe Connect and without merchant-of-record setup.

Why this exists

Stripe Connect in standard mode doesn't support PayPal unless you're a merchant of record. This Worker sits between your Webround store and PayPal, handling the full checkout flow independently.

Flow

Customer clicks PayPal → Worker validates cart via Webround API
                       → Creates Webround order (status: created)
                       → Creates PayPal order
                       → Returns PayPal order ID to frontend

Customer approves      → Frontend captures the PayPal order

PayPal sends webhook   → Worker verifies HMAC signature
                       → Patches Webround order to paid
                       → Webround fires order.paid to your integrations

Structure

src/
  index.ts      # Worker entry point — routes and orchestration
  paypal.ts     # PayPal API (token, create order, capture, webhook verify)
  webround.ts   # Webround API (cart validation, order creation, status update)
  types.ts      # Shared types and Env interface
PayPalButton.tsx  # Webround custom React component (drop into the IDE)
schema.sql        # D1 table to map PayPal order IDs → Webround order IDs
wrangler.jsonc    # Cloudflare Worker config (staging + production)

Setup

1. Create the D1 database

wrangler d1 create my-store-paypal
wrangler d1 execute my-store-paypal --file=schema.sql

2. Set secrets

# secrets-staging.json and secrets-prod.json — never commit these
{
  "WR_API_KEY": "...",
  "PAYPAL_CLIENT_ID": "...",
  "PAYPAL_SECRET": "..."
}

3. Update wrangler.jsonc with your store ID, user ID, database IDs, and webhook IDs.

4. Deploy

make deploy-staging
make deploy-prod

Frontend

Drop PayPalButton.tsx into the Webround built-in React IDE and add it to your cart page. Install @paypal/react-paypal-js from the IDE package manager.

A note on rounding

Stripe and PayPal calculate order totals differently on multi-quantity lines with decimal prices. This Worker aligns PayPal's calculation to Stripe's method to avoid silent discrepancies in accounting exports. See the blog post for the full explanation.

Read more

How I built this — full writeup on blog.webround.com