Fastly Compute

Fastly Compute (JavaScript) still uses the fetch event listener model rather than the modules-style default export you see on Cloudflare Workers. The DaloyJS adapter wraps that registration so you only call one function.

When to choose Fastly Compute

You already use Fastly's edge network and want REST API logic on the same plane.
You want WebAssembly-compiled JS (js-compute-runtime) for tight cold starts.
You're comfortable without node:* modules.

Install

bash

pnpm add @daloyjs/core @fastly/js-compute
pnpm add -D @fastly/cli

Entrypoint

// src/index.ts
/// <reference types="@fastly/js-compute" />
import { installFastlyListener } from "@daloyjs/core/fastly";
import { app } from "./server.js";

installFastlyListener(app);

Under the hood that's equivalent to:

addEventListener("fetch", (event) =>
  event.respondWith(app.fetch(event.request))
);

fastly.toml

Fastly Compute requires manifest_version = 3. The [scripts] build command has to bundle TypeScript to a single JS file first, then run js-compute-runtimeagainst that bundle — the runtime only accepts JavaScript input.

toml

manifest_version = 3
name = "my-api"
language = "javascript"
description = "DaloyJS on Fastly Compute"

[scripts]
# Bundle src/index.ts -> bin/index.js -> bin/main.wasm
build = "esbuild src/index.ts --bundle --format=esm --platform=neutral --outfile=bin/index.js && js-compute-runtime bin/index.js bin/main.wasm"

# Declare every outbound HTTP service your REST API calls as a backend.
# Fastly Compute blocks arbitrary fetch() calls without a declared backend.
[local_server]
  [local_server.backends.auth-service]
    url = "https://auth.internal.example.com"

Declared backends, KV stores, config stores, and secrets live under the same [local_server.*] / [setup.*]tables — see the fastly.toml reference for the full schema.

Deploy