create-caspian-app

Create a new Caspian app, a high-performance Python web framework built on FastAPI and the PulsePoint browser runtime.

The installer and application tooling use Python.

Caspian is in alpha. APIs and generated project structure may change as Caspian develops.

Create an app

With uv (recommended, nothing to install first):

uvx create-caspian-app my-app

Or install the command once:

uv tool install create-caspian-app     # or: pipx install create-caspian-app
create-caspian-app my-app

You'll be asked which features you want:

? What is your project named? (my-app)
? Would you like to use Tailwind CSS? y/N
? Would you like to use MCP (Model Context Protocol)? y/N
? Would you like to use Prisma ORM (Caspian DB)? y/N
? Would you like to use WebSocket? y/N

The installer writes the project, generates a .env with fresh secrets, runs uv sync --group dev, and builds the CSS. When Tailwind is on, it also downloads the pinned, checksum-verified Tailwind standalone compiler. Then:

cd my-app
uv run dev

uv run dev is a shortcut for uv run python main.py; both start the development server. The other everyday tools have short commands too; arguments pass through unchanged:

Skip the questions

Pass flags and -y. Only the flags you pass are turned on:

uvx create-caspian-app my-app --tailwindcss --mcp --prisma --websocket -y
uvx create-caspian-app my-app --prisma --websocket -y

Update an existing app

Run this from the project folder:

uvx --from create-caspian-app casp update project          # latest
uvx --from create-caspian-app casp update project 0.0.1    # a specific version

Running create-caspian-app <name> inside a folder that has a caspian.config.json does the same. The update refreshes the Caspian template files and asks about any features that aren't enabled yet. It removes the files of features you turn off and re-pins the managed dependencies.

An update never overwrites:

• .env
• pyproject.toml (only the managed requirements are re-pinned, with uv add / uv remove)
• uv.lock
• src/app/globals.css (only the Tailwind directives are added or removed)
• prisma/
• any path listed in caspian.config.json → "excludeFiles"

Everything else that comes from the template, such as src/app/index.py, gets overwritten. Add the files you've customized to excludeFiles first.

Requirements

• Python 3.14+ for the installer and generated apps. uv can download Python 3.14 if it is missing.
• uv. If it's missing, the installer tries python -m pip install uv.