The billing framework
for TypeScript

Define plans and features in code. PayKit handles Stripe, webhooks, and usage state - runs inside your app.

import { feature, plan } from "paykitjs"

const messages = feature({ id: "msgs", type: "metered" })
const proModels = feature({ id: "pros", type: "boolean" })

export const free = plan({
  id: "free",
  default: true,
  includes: [
    messages({ limit: 20, reset: "month" }),
  ],
})

export const pro = plan({
  id: "pro",
  price: { amount: 19, interval: "month" },
  includes: [
    messages({ limit: 100, reset: "month" }),
    proModels(),
  ],
})

import { createPayKit } from "paykitjs"
import { free, pro } from "./products"

export const paykit = createPayKit({
  database: env.DATABASE_URL,
  stripe: {
    secretKey: env.STRIPE_SECRET_KEY,
    webhookSecret: env.STRIPE_WEBHOOK_SECRET,
  },
  products: [free, pro],
  on: {
    "subscription.activated": async ({ customer }) => {
      await sendEmail(customer.email, "Welcome to Pro!")
    },
  }
})