Digital products

Ebook download

import {
  Billing,
  DownloadEmails,
  Downloads,
  Offer,
  Purchase,
} from "@byfungsi/sapa";
import { Effect } from "effect";

export const ebook = Effect.gen(function* () {
  const download = yield* Downloads.download({
    asset: { key: "ebook.effect.pdf", revision: 1 },
    duration: "perpetual",
  });
  const email = yield* DownloadEmails.customer({
    asset: { key: "ebook.effect.pdf", revision: 1 },
  });
  const purchase = yield* Purchase.parse({
    key: "ebook.effect.benefits",
    revision: 1,
    provides: [download, email],
  });
  const billing = yield* Billing.oneTime({
    price: { currency: "IDR", amount: 99_000n },
  });
  return yield* Offer.parse({
    key: "ebook.effect",
    revision: 1,
    purchase,
    billing,
  });
});

Install the exact asset revision before registering the offer. Settlement makes the customer eligible; download authorization produces a short-lived URL.

External course enrollment

import { Access, Fulfillment } from "@byfungsi/sapa";

export const course = Effect.gen(function* () {
  const access = yield* Access.entitlements({
    entitlements: ["course.effect.use"],
    duration: "perpetual",
  });
  const delivery = yield* Fulfillment.external({
    binding: { key: "course.effect.delivery", revision: 1 },
    entitlement: "course.effect.use",
  });
  const purchase = yield* Purchase.parse({
    key: "course.effect.enrollment",
    revision: 1,
    provides: [access, delivery],
  });
  const billing = yield* Billing.oneTime({
    price: { currency: "IDR", amount: 499_000n },
  });
  return yield* Offer.parse({
    key: "course.effect",
    revision: 1,
    purchase,
    billing,
  });
});

Settlement retains a fulfillment obligation. A worker executes the exact installed binding with a stable execution identity. Replay and history rebuild must not execute delivery again. Refund processing can retain a reversal obligation rather than deleting the original successful delivery.