Runtime Support

dreamcli runs on Node.js, Bun, and Deno without code changes. A thin RuntimeAdapter interface abstracts the platform-specific edges.

Supported Runtimes

Runtime	Status	Package
Node.js >= 22	Supported	dreamcli (npm)
Bun >= 1.3	Supported	dreamcli (npm)
Deno >= 2.6	Supported	@kjanat/dreamcli (JSR)

How It Works

The core framework never imports platform-specific APIs directly. Instead, a RuntimeAdapter provides:

• argv — command-line arguments
• env — environment variables
• cwd — current working directory
• exit — process exit
• isTTY — terminal detection
• readFile / homedir / configDir — filesystem access

Runtime detection is automatic — dreamcli picks the right adapter at startup.

Explicit Adapter

import { createAdapter } from 'dreamcli/runtime';

const adapter = createAdapter('node');
// or 'bun', 'deno', 'auto' (default)

Deno Permissions

On Deno, the adapter handles permission-safe access to the Deno namespace. If permissions are missing, features degrade gracefully with clear error messages.

deno run --allow-read --allow-env mycli.ts deploy

Testing with Adapters

The test harness uses a built-in test adapter that doesn't touch real process state:

import { runCommand } from 'dreamcli/testkit';

const result = await runCommand(cmd, ['--flag', 'value'], {
	env: { MY_VAR: 'test' },
	// Uses test adapter internally — no real process access
});

What's Next?

• Testing — in-process test harness
• Getting Started — installation per runtime