flue dev

Synopsis

flue dev [--target <node|cloudflare>] [--root <path>] [--output <path>] [--config <path>] [--port <number>] [--env <path>]

Description

flue dev starts a local server, watches project files, and reloads after relevant changes. Editing, creating, or deleting an auto-discovered flue.config.* file restarts the local development session with freshly resolved configuration. Explicit --config <path> files are watched even when they live outside the project root. A configuration restart interrupts active local requests and streaming connections. When an edited configuration is invalid, the command waits for the next configuration change and starts a new session after the error is corrected.

Options

Option	Default	Description
--target <node|cloudflare>	Configuration value	Select the development target. Required unless supplied by configuration.
--root <path>	Selected config-file directory, or config search directory	Select the project root.
--output <path>	<root>/dist	Configure deployment build output. Node development does not write runtime artifacts there.
--config <path>	Auto-discovered flue.config.*	Select a configuration file.
--port <number>	3583	Select the local server port.
--env <path>	<config-base>/.env, when present	Select one alternate .env-format file loaded before configuration. Relative paths resolve from <config-base>. Shell values win.

Target-specific behavior

Node.js

Runs the project through an in-memory Vite module runtime without writing deployment artifacts. On a source change, Flue pauses new agent, workflow, dispatch, and channel admissions, lets accepted work settle, then replaces the loaded application on the same port. Observation-only requests and accepted event streams do not block this drain.

While a reload is draining or loading, new admissions receive a structured 503 response. If changed source does not load, the listener remains available in a failed state and recovers after the next valid edit. Work started outside Flue’s tracked operations, including detached promises created by application handlers, is not part of reload quiescence.

Cloudflare

Starts Vite with the official Workers integration. Cloudflare runtime bindings continue to use the official .dev.vars, .env, and CLOUDFLARE_ENV conventions.

Examples

flue dev
flue dev --target node
flue dev --target cloudflare --port 8787
flue dev --env .env.staging

See the CLI overview for the complete development workflow.