CLI workflow

The Windmill CLI provides commands to scaffold, develop and deploy full-code apps entirely from your terminal.

Create a new app

wmill app new

The interactive wizard prompts for:

1. Summary: short description of the app
2. Path: app path (e.g., f/folder/my_app)
3. Framework: React 19, React 18 or Svelte 5
4. Data configuration: optional datatable and schema setup

This creates a directory with the .raw_app suffix (or __raw_app if nonDottedPaths: true is set in wmill.yaml):

f/folder/my_app.raw_app/   # or my_app__raw_app/
├── raw_app.yaml
├── package.json
├── index.tsx
├── App.tsx
├── index.css
├── AGENTS.md
├── CLAUDE.md
├── DATATABLES.md
├── backend/
│   ├── a.yaml
│   └── a.ts
└── sql_to_apply/
    └── README.md

After scaffolding, install dependencies:

cd f/folder/my_app.raw_app   # or my_app__raw_app
npm install

Start the dev server

From inside the app directory:

cd f/folder/my_app.raw_app   # or my_app__raw_app
wmill app dev

Options

Option	Description
--port <number>	Dev server port (default: 4000)
--host <string>	Dev server host (default: localhost)
--entry <string>	Entry point file (default: index.tsx or index.ts)
--no-open	Don't auto-open the browser

Dev server features

• Hot module replacement: frontend changes reload instantly
• WebSocket backend: backend runnables execute on Windmill workers with results streamed back
• Type generation: wmill.d.ts is regenerated when runnables change
• Schema inference: runnable parameter types are inferred without modifying YAML files
• SQL migrations: a modal appears for pending files in sql_to_apply/

Generate agent documentation

From the app directory:

wmill app generate-agents

Generates or updates:

• AGENTS.md: instructions for AI coding agents describing the project structure
• DATATABLES.md: data table schema documentation

Generate lock files

From the app directory, generate .lock files for each backend runnable that has dependencies (TypeScript, Python, PHP) using the wmill generate-metadata command:

wmill generate-metadata

Option	Description
--yes, -y	Skip confirmation prompt
--dry-run	Show what would be updated
--default-ts <bun|deno>	Default TypeScript runtime

Legacy command

Prior to the unified command, this was done with wmill app generate-locks. This command is now deprecated but still works.

Deploy with sync

Full-code apps are deployed using the standard sync commands:

Push to Windmill

wmill sync push

The push process:

1. Reads raw_app.yaml for metadata and policy
2. Loads backend runnables from backend/
3. Collects frontend files (excluding node_modules, dist, backend/, etc.)
4. Bundles frontend code with esbuild
5. Uploads everything as a multipart request (app JSON + JS bundle + CSS bundle)

Pull from Windmill

wmill sync pull

The pull process:

1. Fetches the app definition from the API
2. Extracts frontend files to the app directory
3. Writes raw_app.yaml with metadata
4. Extracts backend runnables to backend/ with individual .yaml, code and .lock files

Typical workflow

# 1. Create a new app
wmill app new

# 2. Install dependencies
cd f/folder/my_app.raw_app   # or my_app__raw_app   # or my_app__raw_app
npm install

# 3. Develop locally with hot reload
wmill app dev

# 4. Generate lock files before deploying
wmill generate-metadata

# 5. Deploy to Windmill
wmill sync push

Command-line interface

Full CLI reference.

Project structure

File layout of a full-code app.