---
title: "Bun + Elysia + SQLite"
description: "Thin Elysia fetch adapter over the private checkout kernel with in-memory Bun SQLite."
---

> Documentation Index
> Fetch the complete documentation index at: https://paykernel-docs.abshahin.workers.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# Bun + Elysia + SQLite

`@paykernel/example-bun-elysia-sqlite` is a **private** workspace host (`private: true`). It is **not** published and is **not** [`@paykernel/integration-elysia`](/integrations/elysia). The [checkout kernel](/examples/checkout-kernel) owns checkout, inbox, and reconciliation.

Source: [`examples/bun-elysia-sqlite`](https://github.com/aashahin/paykernel/tree/main/examples/bun-elysia-sqlite) ([README](https://github.com/aashahin/paykernel/blob/main/examples/bun-elysia-sqlite/README.md)).

## Mapping

[`createElysiaCheckoutApp`](https://github.com/aashahin/paykernel/blob/main/examples/bun-elysia-sqlite/src/app.ts) returns an `Elysia` instance. JSON routes use `parse: "none"` and `readRequestJson(request)`. Imports and Stripe route as in source:

```ts
import { Elysia } from "elysia";
import { elysiaWebhook } from "@paykernel/integration-elysia";
import {
  checkoutJsonResponse,
  createCheckoutHandlers,
  createPaymentInputFromUnknown,
  gatewayPaymentIdFromUnknown,
  readRequestJson,
  type CheckoutHttpOptions,
  type CheckoutKernel,
} from "@paykernel/example-checkout-kernel";

const noParse = { parse: "none" as const };

app.use(
  elysiaWebhook("/webhooks/stripe", {
gateway: kernel.webhook.gateway,
client: kernel.webhook.client,
engine: kernel.webhook.engine,
handler: kernel.webhook.handler,
  }),
);
```

`elysiaWebhook` posts with `parse: "none"`, then `await request.text()`, then `processWebhookHttp`. Do not put a JSON body parser on that path. Stripe HMAC needs the original bytes.

HTTP status lives in the checkout kernel (`mapInboxOutcome`), **not** in [`@paykernel/webhooks`](/packages/webhooks). Fulfillment runs only after an inbox **claim**, and only when the rematched event is `payment.succeeded` / `capture.completed` with `payment.status === "paid"`. Never fulfill in `onWebhookVerified`. Never `createPayment` again after an indeterminate create — lookup + `decideReconciliationPolicy` only.

This package does not reimplement `mapInboxOutcome` or HMAC signing. Stripe fixtures live in the kernel.

## `:memory:` is process-local

Default `createCheckoutKernel()` uses in-memory Bun SQLite after an explicit `migrateSqliteAdapter`. **One process, one memory DB** — not multi-host or multi-region. See [SQLite store](/stores/sqlite).

## Routes

`createElysiaCheckoutApp(kernel)` wires:

| Method | Path | Notes |
| --- | --- | --- |
| `POST` | `/payments` | `parse: "none"` + `readRequestJson`. Invalid JSON → `400 { "error": "invalid_json" }`. |
| `POST` | `/webhooks/stripe` | `elysiaWebhook` / `request.text()`. |
| `GET` | `/orders/:orderId` | Order book. |
| `POST` | `/internal/reconcile` | **Test hook.** Unauthenticated. Do not deploy (`enableTestHooks`). |
| `POST` | `/internal/provider-paid` | **Test hook.** Unauthenticated. Do not deploy. |
| `GET` | `/internal/create-count` | **Test hook.** Unauthenticated. Do not deploy (`enableTestHooks`). |

:::caution[Test hooks]
Tests wrap the app as `{ fetch: (req) => app.handle(req) }` with `{ enableTestHooks: true }`. Without the flag, `/internal/reconcile` and `/internal/create-count` return `404`. `bun run start` leaves the flag off. Do not deploy this example as-is.
:::

Shared failure paths: [Checkout kernel](/examples/checkout-kernel) (`runCheckoutHttpScenarios("elysia", …)`).

## Run

```bash
bun install
bun test
# optional listen (PORT, default 3000)
bun run start
```

`bun run start` → `bun src/index.ts` → `app.listen(port)`. Tests drive `app.handle(req)` and do not use that listener.

## Related

- [Checkout kernel](/examples/checkout-kernel) · [Elysia integration](/integrations/elysia) · [SQLite store](/stores/sqlite) · [Webhooks](/guides/webhooks)

Source: https://paykernel-docs.abshahin.workers.dev/examples/bun-elysia-sqlite/index.mdx