Dev Server

Command

ev dev

No flags needed — configuration comes from ev.config.ts or convention-based defaults.

What It Does

ev dev starts two servers simultaneously:

Server	Default Port	Purpose
Webpack Dev Server	3000	Client bundle with Hot Module Replacement (HMR)
API Server	3001	Server functions + route handlers, auto-started after first build

The client dev server automatically proxies /api/* requests to the API server.

Configuration

// ev.config.ts
import { defineConfig } from "@evjs/ev";

export default defineConfig({
  entry: "./src/main.tsx",         // Default
  html: "./index.html",            // Default
  dev: {
    port: 3000,                   // WDS port
    https: false,                 // HTTPS mode
  },
  server: {
    endpoint: "/api/fn",           // Default
    runtime: "node",               // Or "bun", "deno", etc.
    dev: {
      port: 3001,                 // API port
      https: false,               // HTTPS for API server
    },
  },
});

How It Works

1. loadConfig(cwd) loads ev.config.ts.
2. resolveConfig() applies defaults, then plugin.setup() collects lifecycle hooks.
3. hooks.buildStart() runs before compilation.
4. BundlerAdapter.dev() is invoked (applying plugin bundler hooks to the config).
5. Starts WebpackDevServer for client HMR.
6. The adapter signals onServerBundleReady after discovery.
7. The CLI core auto-starts the API server via @evjs/server/node.
8. Sets up reverse proxy: devServer.proxy["/api"] → localhost:3001.

Custom Runtimes

The server.runtime field supports any executable:

• "node" (default) — uses --watch for auto-restart
• "bun" — passes args as-is
• "deno run --allow-net" — split on whitespace, extra args forwarded

warning

The ECMA environment adapter (@evjs/server/ecma) only exports a { fetch } handler — it does not start a listening server. For ev dev, you must use a runtime that starts an HTTP server (default: "node").

Programmatic API

ev dev and ev build can also be used programmatically:

import { dev, build } from "@evjs/cli";

// Start dev server (loads ev.config.ts and uses defaults)
await dev({ dev: { port: 3000 } }, { cwd: "./my-app" });

// Run production build
await build({ entry: "./src/main.tsx" }, { cwd: "./my-app" });

Transport

initTransport is called automatically by createApp() to configure how the client communicates with the server.

• In dev mode: WDS proxies /api/* → :3001, so the default /api/fn endpoint works automatically
• In production: client and server are typically on the same origin
• The transport is runtime-agnostic — the client always posts to the same endpoint regardless of server runtime