> > [!WARNING] > Deprecated. SvelteKit 3 has an official Bun adapter, > @sveltejs/adapter-bun, which > also compiles the app into a single executable. Migrate to it, see > Migrating… > Source: https://orochibraru.com/svelte-smol/canary/docs/readme · Site index: https://orochibraru.com/llms.txt # Svelte Smol Adapter > [!WARNING] > **Deprecated.** SvelteKit 3 has an official Bun adapter, > [`@sveltejs/adapter-bun`](https://svelte.dev/docs/kit/adapter-bun), which > also compiles the app into a single executable. Migrate to it, see > [Migrating to `@sveltejs/adapter-bun`](#migrating-to-sveltejsadapter-bun). > This package only gets SvelteKit 2 fixes until the repository is archived. A [SvelteKit](https://svelte.dev/docs/kit) adapter that compiles your app into a **single standalone executable** with `bun build --compile`. No `node_modules`, no JS files to ship, just one binary plus its static assets. ## Install ```bash bun add -d @orochibraru/svelte-smol ``` Every merge to `main` ships as `@orochibraru/svelte-smol@canary`; stable releases go out under `latest`. ## Usage ```typescript // svelte.config.js import adapter from "@orochibraru/svelte-smol"; export default { kit: { adapter: adapter(), }, }; ``` The compile step runs under the Bun runtime, so build with: ```bash bun run vite build ``` ## Migrating to `@sveltejs/adapter-bun` The official adapter needs SvelteKit 3 and Bun 1.4 or newer. These steps work from svelte-smol on either SvelteKit version. 1. Swap the packages: ```bash bun remove @orochibraru/svelte-smol bun add -d @sveltejs/kit@^3 @sveltejs/adapter-bun ``` 2. Configure the adapter in the Vite plugin, and remove `adapter` from `svelte.config.js` if you were on SvelteKit 2: ```typescript // vite.config.js import adapter from "@sveltejs/adapter-bun"; import { sveltekit } from "@sveltejs/kit/vite"; import { defineConfig } from "vite"; export default defineConfig({ plugins: [ sveltekit({ adapter: adapter({ buildOptions: { compile: true } }) }), ], }); ``` Compiling is opt-in. Without `buildOptions.compile`, the build is a Vite-built `build/index.js` run with `bun ./build`, and the app's production `dependencies` are not bundled into it: ship a production `node_modules` next to it. That is also the mode for native (`.node`) addons, as `compile: false` was here. 3. Build under the Bun runtime: `bun run --bun vite build`. 4. Rename your options: | svelte-smol, SvelteKit 2 | svelte-smol, SvelteKit 3 | `@sveltejs/adapter-bun` | | --------------------------------- | ----------------------------------------------- | ----------------------------------------- | | `compile: true` (default) | `buildOptions: { compile: true }` (default) | `buildOptions: { compile: true }` | | `compile: false` | `buildOptions: { compile: false }` | leave `buildOptions.compile` unset | | `target: "bun-linux-x64"` | `buildOptions: { compile: "bun-linux-x64" }` | same as svelte-smol on SvelteKit 3 | | `name: "app"` | `buildOptions: { compile: { outfile: "app" } }` | same as svelte-smol on SvelteKit 3 | | `bytecode`, `minify`, `sourcemap` | `buildOptions.*` | `buildOptions.*` | | `serveOptions` | `serverOptions` | `serverOptions` (JSON-serializable only) | | `serveAssets: false` | removed | removed, assets are always served | | n/a | `buildOptions.splitting` | removed | | `healthcheck` | `healthcheck` | removed, see step 6 | `out`, `precompress` and `envPrefix` keep their meaning. `precompress` is still ignored when compiling. 5. Update your environment: - `IDLE_TIMEOUT` becomes `CONNECTION_IDLE_TIMEOUT` (max `255`). - `ASSETS_DIR`, `HEALTHCHECK_PATH` and `HEALTHCHECK_TIMEOUT` are gone. - `ORIGIN` is gone. The public origin comes from `paths.origin` in the SvelteKit config, fixed at build time, else from the request and the forwarded headers, assuming `https` unless `PROTOCOL_HEADER` says otherwise. An app served over plain HTTP with neither set fails the CSRF check on every form action: set `paths.origin`, or set `PROTOCOL_HEADER=x-forwarded-proto` behind a proxy that sends it. - With `envPrefix`, the server refuses to start when it sees a prefixed variable it doesn't know. Delete leftovers like `MY_APP_ORIGIN` or `MY_APP_HEALTHCHECK_TIMEOUT`. 6. Replace the health check. The endpoint is a regular route: ```typescript // src/routes/_health/+server.ts export const prerender = false; export const GET = () => Response.json( { status: "ok" }, { headers: { "cache-control": "no-store" } }, ); ``` The probe is a script you compile yourself, so it still runs in an image without `curl`: ```typescript // healthcheck.ts const port = process.env.PORT ?? "3000"; try { const response = await fetch(`http://127.0.0.1:${port}/_health`, { signal: AbortSignal.timeout(2000), }); process.exit(response.ok ? 0 : 1); } catch { process.exit(1); } ``` ```dockerfile RUN bun build --compile --minify ./healthcheck.ts --outfile build/healthcheck HEALTHCHECK --interval=30s --timeout=5s --start-period=5s --retries=3 \ CMD ["./build/healthcheck"] ``` Pass the same `--target` as `buildOptions.compile` when cross-compiling. One behaviour has no replacement: a compiled executable answers a `Range` request on an embedded asset with `200` and the whole file, so a `