Determine app module path correctly even when in a submodule. A bit cleaner dev options.

README.md

@@ -1,137 +1,96 @@
 # fastapi-vue-setup
 
-Tool to create or patch FastAPI project with a Vue frontend, with integrated build and development systems. The Python package will not need any JS runtime because it includes a prebuilt Vue frontend in it. For development (Vite and FastAPI auto reloads) and building the package one of npm, deno or bun is required (node is recommended due to bugs in deno and bun).
+Create or patch a FastAPI + Vue project with an integrated dev/build workflow.
 
-## Features
+- Development: one command runs Vite + FastAPI (reloads)
+- Production: `uv build` bakes the built Vue assets into the Python package (no Node/JS runtime needed to *run* the installed package)
 
-- **No JavaScript**: Your Python package can be installed and used without any JS runtime
+## Quick start
-- **Integrated build system**: Vue frontend builds into Python package during `uv build`
-- **Development server**: Single command runs Vite + FastAPI with hot-reload
-- **Optimized static serving**: Caching, zstd compression and SPA support
 
-## Installation
+Install [UV](https://docs.astral.sh/uv/) and any JS runtime (node, deno, or bun).
 
-Install [uv](https://docs.astral.sh/uv/getting-started/installation/), then:
+This README uses `my-app` as the example project name:
 
-```sh
+- project directory: `my-app/`
-uv tool install fastapi-vue-setup
+- Python module: `my_app`
-fastapi-vue-setup --help
+- env prefix: `MY_APP`
-```
+- CLI command: `my-app`
 
-Or run directly:
+Create a new project in `./my-app`:
 
 ```sh
 uvx fastapi-vue-setup my-app
 ```
 
-## Usage
+Once in your source tree, you will typically use `.` for the path. If there is an existing project, `fastapi-vue-setup` will do its best to find and patch a backend module and create or patch a Vue project in `frontend/`. The integration can be upgraded by running a new version of `fastapi-vue-setup` on it, preserving earlier default ports and user customizations.
 
-The script may be used to create an all new project folder or to patch or update an existing project to use this framework. It autodetects the project folder given and performs the appropriate actions.
+## In your project
 
-### Create a new project
+ℹ️ Everything below is meant to be run within your project source tree.
+
+The setup creates a CLI entry for your package, so that it becomes a command to run, not a Python module nor `fastapi myapp...`. The CLI main can be customized, although --listen should be kept for devserver compatibility.
+
+You can choose the JS runtime with environment `JS_RUNTIME` (e.g. `node`, `deno`, `bun`, or path to one). This is used by the build and the devserver scripts. By default any available runtime on the system is chosen.
+
+### Development server (Vite + FastAPI)
 
 ```sh
-fastapi-vue-setup my-app
+uv run scripts/devserver.py [args]
 ```
 
-This will:
+ℹ️ Arguments are forwarded to the main CLI, except that `--listen` controls where Vite listens, and `--backend` is passed to main CLI as `--listen`.
 
-1. Run `uv init my-app`
+### Production
-2. Run `create-vue frontend` (interactive - choose your Vue options)
-3. Patch the project with FastAPI integration
-4. Install dependencies via `uv add`
 
-### Patch an existing project
+Build the Python package (this compiles the Vue frontend) and run the production server:
-
-You should have your pyproject.toml at the current working directory, and Vue with its package.json under `frontend/`. If either one is missing, new applications will be initialised. Otherwise we only patch what can be patched without breaking your existing projects.
 
 ```sh
-fastapi-vue-setup .
+uv build && uv run my-app [args]
 ```
 
-### CLI Options
+Once happy with it, publish the package
 
-```
+```sh
-fastapi-vue-setup [project-dir] [options]
+uv build && uv publish
-
-Options:
-  --module-name NAME    Python module name (auto-detected from pyproject.toml)
-  --dry-run             Preview changes without modifying files
 ```
 
-## Port Configuration
+Afterwards, you can easily run it anywhere, no JS runtimes required:
 
-In development, you access the Vite dev server at `http://localhost:5173`. Vite proxies `/api/*` requests to FastAPI at port 5180. Ports and hosts of Vite and FastAPI are configurable by `devserver.py` arguments.
+```sh
-
+uvx my-app [args]
-In production, FastAPI serves both the API and static files at `http://localhost:5080`. Configurable by `host:port` argument with defaults set in `__main__.py`
-
-## Main CLI
-
-If your project didn't already have `__main__.py`, we create one that runs the FastAPI app with richer configuration than what the FastAPI CLI offers. Running your module starts it in production mode, and optionally host:port may be given as argument to specify where it listens.
-
-If you are running behind a reverse proxy like [Caddy](https://caddyserver.com/) on localhost, your app will trust the proxy headers it sends. However, if you need to configure another proxy host or IP, set `FORWARDED_ALLOW_IPS` env variable before running the server.
-
-The devserver script depends on this CLI entry for running the backend. You will have to modify the `devserver.py` script if your app has its own incompatible main module. Note that we set FastAPI debug mode and Uvicorn reload when configured via `FASTAPI_VUE_BACKEND_URL` env variable (set by `devserver.py`), while for normal production use these stay disabled. The same variable also controls static files serving (disabled in dev mode).
-
-
-## Vite Plugin Configuration
-
-The `fastapiVue()` plugin in `vite.config.ts` accepts options to customize proxy behavior:
-
-```js
-import fastapiVue from "./vite-plugin-fastapi.js";
-
-export default defineConfig({
-  plugins: [
-    vue(),
-    // Default: proxies only /api
-    fastapiVue(),
-
-    // Or specify custom paths to proxy to backend
-    fastapiVue({ paths: ["/api", "/auth", "/ws"] }),
-  ],
-});
 ```
 
-The plugin reads environment `FASTAPI_VUE_BACKEND_URL` (default: `http://localhost:5180`) to determine where to proxy requests. This is set automatically by `devserver.py`.
+ℹ️ Instead of `uvx` you may consider `uv tool install`, oldskool `pip install` or whatever best suits you.
 
-## Project Structure
+### Vite plugin
+
+The generated Vite plugin lives in `frontend/vite-plugin-fastapi.js` and defaults to proxying `/api`.
+
+It reads `MY_APP_BACKEND_URL` to know where to proxy; if unset it falls back to your configured default backend port.
+
+## Project layout (typical)
 
 ```
 my-app/
-├── frontend/                 # Vue application
+├── frontend/                    # Vue app (Vite)
 │   ├── src/
 │   ├── vite-plugin-fastapi.js
-│   ├── vite.config.js
 │   └── package.json
-├── my_app/                   # Python module (files included in sdist)
+├── my_app/                      # Python package
-│   ├── __init__.py
 │   ├── __main__.py              # CLI entrypoint
-│   ├── app.py                # FastAPI application
+│   ├── app.py                   # FastAPI app
-│   └── frontend-build/       # Built frontend (gitignored)
+│   └── frontend-build/          # built assets (included in distributions)
-├── scripts/
+├── pyproject.toml
-│   ├── devserver.py          # CLI dev server (only in source tree)
+└── scripts/
-│   └── fastapi-vue/
+    ├── devserver.py             # Run Vite and FastAPI together in dev mode
-│       ├── build-frontend.py
+    └── fastapi-vue/             # Dev utilities (only on the source tree)
-│       └── util.py
+        ├── build-frontend.py
-└── pyproject.toml
+        ├── buildutil.py
+        └── devutil.py
 ```
 
-The project directory tree looks roughly like this after project creation or patching. The script finds your existing app module and other files and patches them with minimal changes to enable the Vue-FastAPI interconnection. New Python and Vue projects are created automatically if none exist.
+## The fastapi-vue runtime module
 
-## Development Workflow
+The backend runs the FastAPI app and serves the frontend build using the companion package in [fastapi-vue/README.md](fastapi-vue/README.md). Your project will depend on Fastapi and this lightweight module.
 
-```bash
+ℹ️ Development functionality is in `scripts/fastapi-vue/` directly in your source tree, and is not to be confused with this runtime module. Only the runtime is installed with your package.
-# Start dev server (runs both Vite and FastAPI)
-uv run scripts/devserver.py
-
-# Build for production
-uv build
-
-# Run production server
-uv run my-app
-```
-
-## Frontend serving
-
-Your FastAPI app will use [fastapi-vue](https://git.zi.fi/LeoVasanko/fastapi-vue) to serve the frontend files. Refer to that package's documentation for further configuration.

fastapi-vue/README.md

@@ -1,29 +1,25 @@
 # fastapi-vue
 
-Implements Single-Page-App serving at site root with FastAPI, that the standard StaticFiles module cannot handle. This also caches and zstd compresses the files for lightning-fast operation. This is primarily meant for use with Vue frontend, but technically can host any static files in a similar manner.
+Runtime helpers for FastAPI + Vite/Vue projects.
 
-## Installation
+## Overview
 
-Script [fastapi-vue-setup](https://git.zi.fi/LeoVasanko/fastapi-vue-setup) should normally be used to convert or create a project with connection between FastAPI and Vue. The target project will depend on this package to serve its static files.
+This package provides:
 
-```sh
+- `fastapi_vue.Frontend`: serves built SPA assets (with SPA support, caching, and optional zstd)
-uvx fastapi-vue-setup --help
+- `fastapi_vue.server.run`: a small Uvicorn runner with convenient `listen` endpoint parsing
-```
 
-Refer to instructions below for further configuration.
+## Quickstart
 
-## Usage
+Serve built frontend assets from `frontend-build/`:
 
 ```python
+from pathlib import Path
 from contextlib import asynccontextmanager
 from fastapi import FastAPI
 from fastapi_vue import Frontend
 
-frontend = Frontend(
+frontend = Frontend(Path(__file__).with_name("frontend-build"), spa=True)
-    Path(__file__).with_name("frontend-build"),
-    spa=True,
-    cached=["/assets/"],
-)
 
 @asynccontextmanager
 async def lifespan(app: FastAPI):
@@ -38,10 +34,35 @@ app = FastAPI(lifespan=lifespan)
 frontend.route(app, "/")
 ```
 
-## Configuration
+## Frontend
 
-- `directory`: Path to static files directory
+`Frontend` serves a directory with:
-- `spa`: Enable SPA mode (serve index.html for unknown routes)
+
-- `cached`: Path prefixes for immutable cache headers (browser won't check for changes)
+- RAM caching, with zstd compression when smaller than original
-- `favicon`: Path to serve at `/favicon.ico` (e.g., `"/logo.png"` will be served as `image/png`)
+- Browser caching: ETag + Last-Modified, Immutable assets
+- Favicon mapping (serve PNG or other images there instead)
+- SPA routing (serve browsers index.html at all paths not otherwise handled)
+
+Dev-mode behavior with `FastAPI(debug=True)`: requests error HTTP 409 with a message telling you to use the Vite dev server instead. Avoids accidentally using outdated `frontend-build` during development.
+
+- `directory`: Path on local filesystem
+- `index`: Index file name (default: `index.html`)
+- `spa`: Serve index at any path (default: `False`)
+- `catch_all`: Register a single catch-all handler instead of a route to each file; default for SPA
+- `cached`: Path prefixes treated as immutable (default: `/assets/`)
+- `favicon`: Optional path or glob (e.g. `/assets/logo*.png`)
 - `zstdlevel`: Compression level (default: 18)
+
+ℹ️ Even when your page has a meta tag giving favicon location, browsers still try loading `/favicon.ico` whenever looking at something else. We find it more convenient to simply serve the image where the browser expects it, with correct MIME type. This also allows having a default favicon for your application that can be easily overriden at the reverse proxy (Caddy, Nginx) to serve the company branding if needed in deployment.
+
+## Server runner
+
+When you need more flexibility than `fastapi` CLI can provide (e.g. CLI arguments to your own program), you may use this convenience to run FastAPI app with Uvicorn startup on given `listen` endpoints. Runs in the same process if possible but delegates to `uvicorn.run()` for auto-reloads and multiple workers. This would typically be called from your CLI main, which can set its own env variables to pass information to the FastAPI instances that run (Python imports only work in same-process mode).
+
+```python
+from fastapi_vue import server
+
+server.run("my_app.app:app", listen=["localhost:8000"])
+```
+
+- As a deployment option, environment `FORWARDED_ALLOW_IPS` controls `X-Forwarded` trusted IPs (default: `127.0.0.1,::1`).

fastapi-vue/fastapi_vue/staticfiles.py

@@ -276,6 +276,6 @@ def _devmode_respond(request: Request, name=""):
     return JSONResponse(
         status_code=409,
         content={
-            "detail": "Frontend assets served by Vite in debug mode. You are on backend, connect to frontend instead."
+            "detail": "[devmode] Not serving frontend files here. Should you connect to Vite instead?"
         },
     )

fastapi_vue_setup.py

@@ -21,14 +21,12 @@ import subprocess
 import sys
 from pathlib import Path
 from textwrap import indent
+from typing import Literal
 
 import tomlkit
 
 version = importlib.metadata.version("fastapi-vue-setup")
 
-# Track Python files written/patched for ruff formatting
-_python_files_to_format: list[Path] = []
-
 # Template directory
 TEMPLATE_DIR = Path(__file__).parent / "template"
 
@@ -41,21 +39,55 @@ def print_boxed(text: str) -> None:
     print(f"╰{'─' * width}╯")
 
 
-def ruff_sort_imports(files: list[Path], dry: bool = False) -> None:
+def ruff_format_content(
-    """Run ruff to sort imports in the given Python files."""
+    content: str, target_path: Path, *, mode: Literal["isort", "full"] = "full"
-    if not files:
+) -> str:
-        return
+    """Format Python content using ruff with project settings.
-    py_files = [str(f) for f in files if f.suffix == ".py" and f.exists()]
+
-    if not py_files:
+    Writes to a temp file next to target, runs ruff check (import sorting)
-        return
+    and optionally ruff format on it, reads back the result, and cleans up.
-    if dry:
+    Returns the formatted content, or original if ruff fails.
-        print(f"🔧 Would run ruff import sorting on {len(py_files)} files")
+
-        return
+    mode='isort' only sorts imports; mode='full' also formats.
-    print("🔧 Ruff isort on modified files")
+    """
+    temp_file = target_path.with_suffix(".new.py")
+    try:
+        temp_file.write_text(content, "UTF-8", newline="\n")
+        # Sort imports first
         subprocess.run(
-        [sys.executable, "-m", "ruff", "check", "--select", "I", "--fix", *py_files],
+            [
-        stdout=subprocess.DEVNULL,
+                "uv",
+                "run",
+                "--with",
+                "ruff",
+                "ruff",
+                "check",
+                "--select",
+                "I",
+                "--fix",
+                str(temp_file),
+            ],
+            cwd=target_path.parent,
+            capture_output=True,
         )
+        if mode == "isort":
+            return temp_file.read_text("UTF-8")
+        # Then format
+        result = subprocess.run(
+            ["uv", "run", "--with", "ruff", "ruff", "format", str(temp_file)],
+            cwd=target_path.parent,
+            capture_output=True,
+        )
+        if result.returncode == 0:
+            return temp_file.read_text("UTF-8")
+    except Exception:
+        pass
+    finally:
+        try:
+            temp_file.unlink(missing_ok=True)
+        except Exception:
+            pass
+    return content
 
 
 def uv_add_packages(
@@ -228,23 +260,20 @@ def find_import_insertion_line(source: str) -> int:
     return 2 if source.startswith("#!") else 1
 
 
-def extract_existing_ports(project_dir: Path) -> tuple[int, int, int] | None:
+def extract_existing_ports(
+    project_dir: Path, main: Path
+) -> tuple[int, int, int] | None:
     """Extract existing port configuration from project files.
 
     Returns (default, vite, dev) or None if not found.
     """
-    module_name = find_module_name(project_dir)
-    if not module_name:
-        return None
-
     default_port = None
     vite_port = None
     dev_port = None
 
-    # Try to extract DEFAULT_PORT from __main__.py
+    # Try to extract DEFAULT_PORT from the CLI main module
-    main_file = project_dir / module_name / "__main__.py"
+    if main.exists():
-    if main_file.exists():
+        content = main.read_text("UTF-8")
-        content = main_file.read_text("UTF-8")
         match = re.search(r"DEFAULT_PORT\s*=\s*(\d+)", content)
         if match:
             default_port = int(match.group(1))
@@ -402,10 +431,43 @@ def _find_app_in_subpackage(subpkg_dir: Path) -> tuple[Path, str] | None:
     return None
 
 
-def _find_existing_cli_entrypoint(project_dir: Path, module_name: str) -> str | None:
+def _add_devmode_to_main(content: str) -> str:
+    """Add DEVMODE variable to an existing main module."""
+    lines = content.splitlines()
+
+    # Check if os is imported
+    has_os_import = any("import os" in line for line in lines)
+
+    # Find the first import line
+    insert_idx = 0
+    for i, line in enumerate(lines):
+        stripped = line.strip()
+        if stripped.startswith("import ") or stripped.startswith("from "):
+            insert_idx = i + 1
+        elif stripped and not stripped.startswith("#"):
+            break
+
+    # Insert imports and DEVMODE after existing imports
+    new_lines = []
+    if not has_os_import:
+        new_lines.append("import os")
+    new_lines.extend(
+        [
+            "",
+            "# Added by fastapi-vue-setup",
+            'DEVMODE = os.getenv("ENVPREFIX_DEV") == "1"',
+            "",
+        ]
+    )
+
+    lines[insert_idx:insert_idx] = new_lines
+    return "\n".join(lines)
+
+
+def _find_existing_cli_module_path(project_dir: Path, module_name: str) -> str | None:
     """Check if pyproject.toml already has a CLI entrypoint for this module.
 
-    Returns the entrypoint string if found, None otherwise.
+    Returns the module path (e.g., 'module.subpkg.__main__') if found, None otherwise.
     """
     pyproject = project_dir / "pyproject.toml"
     if not pyproject.exists():
@@ -423,7 +485,10 @@ def _find_existing_cli_entrypoint(project_dir: Path, module_name: str) -> str |
     # Look for any script that references our module
     for script_name, entry in scripts.items():
         if isinstance(entry, str) and entry.startswith(f"{module_name}."):
-            return f'{script_name} = "{entry}"'
+            # Extract module path from "module.subpkg.__main__:main"
+            if ":" in entry:
+                module_path, _ = entry.rsplit(":", 1)
+                return module_path
 
     return None
 
@@ -492,7 +557,7 @@ def render_template(template: str, **kwargs) -> str:
 
 
 def patch_app_file(
-    path: Path, module_name: str, app_var: str, dry: bool = False
+    path: Path, main_module_path: str, app_var: str, dry: bool = False
 ) -> bool:
     """Patch an existing app.py with frontend integration.
 
@@ -510,7 +575,7 @@ def patch_app_file(
 
     # Check what's already patched
     has_frontend = "from fastapi_vue import Frontend" in content
-    has_devmode = f"from {module_name}.__main__ import DEVMODE" in content
+    has_devmode = f"from {main_module_path} import DEVMODE" in content
     has_debug_arg = re.search(r"FastAPI\s*\([^)]*debug\s*=", content) is not None
     has_lifespan = "await frontend.load()" in content
 
@@ -525,7 +590,7 @@ def patch_app_file(
     if not has_frontend:
         imports.extend(["from pathlib import Path", "from fastapi_vue import Frontend"])
     if not has_devmode:
-        imports.append(f"from {module_name}.__main__ import DEVMODE")
+        imports.append(f"from {main_module_path} import DEVMODE")
     if imports:
         insert_line = find_import_insertion_line(content)
         lines = content.splitlines(keepends=True)
@@ -654,8 +719,9 @@ def patch_app_file(
         print(f"✅ Would patch {path}")
         return True
 
+    # Sort imports only (avoid full formatting of user code)
+    content = ruff_format_content(content, path, mode="isort")
     path.write_text(content, "UTF-8", newline="\n")
-    _python_files_to_format.append(path)
     print(f"✅ Patched {path}")
 
     if not lifespan_patched:
@@ -776,7 +842,7 @@ def patch_frontend_health_check(frontend_dir: Path, dry: bool = False) -> bool:
             target_file = app_vue
 
     if target_file is None:
-        print("ℹ️  No Vue file found to patch, skipping frontend health check")
+        print("ℹ️  No default App.vue found to patch, not adding /api/health check")
         return False
 
     original_content = target_file.read_text("UTF-8")
@@ -821,7 +887,7 @@ def patch_frontend_health_check(frontend_dir: Path, dry: bool = False) -> bool:
     else:
         # Minimal App.vue - only patch if it contains the default welcome message
         if "<h1>You did it!</h1>" not in content:
-            print(f"ℹ️  Skipping {target_file} (not a default Vue template)")
+            print(f"ℹ️  Skipping {target_file} (not a Vue demo app)")
             return False
         # Insert before the </p> tag
         template_end = content.find("</template>")
@@ -903,13 +969,20 @@ def write_file(
     the content will be written to fallback_path instead of being skipped.
 
     If force=True, always overwrite without checking for upgrade marker.
+
+    Python files (.py) are automatically formatted using ruff with the project's
+    settings before writing.
     """
+    # Format Python content using project settings before any comparison/writing
+    if path.suffix == ".py":
+        content = ruff_format_content(content, path)
+
     exists = path.exists()
     if exists and not overwrite:
         print(f"⚠️  Skipping {path} (exists)")
         return False
 
-    # Check if content is the same
+    # Check if content is the same (new content already formatted)
     if exists:
         existing_content = path.read_text("UTF-8")
         if existing_content == content:
@@ -935,8 +1008,6 @@ def write_file(
     path.write_text(content, "UTF-8", newline="\n")
     if executable and sys.platform != "win32":
         path.chmod(path.stat().st_mode | 0o111)
-    if path.suffix == ".py":
-        _python_files_to_format.append(path)
     action = "Updated" if exists else "Created"
     print(f"✅ {action} {path}")
     return True
@@ -949,11 +1020,16 @@ def _write_fallback_file(
     dry: bool,
     executable: bool,
 ) -> bool:
-    """Write content to a fallback .new.py file when original can't be overwritten."""
+    """Write content to a fallback .new.py file when original can't be overwritten.
-    # Check if fallback already has same content
+
+    Note: content should already be formatted before calling this function.
+    """
+    # Check if fallback already has same content (content already formatted)
     if fallback_path.exists():
-        if fallback_path.read_text("UTF-8") == content:
+        existing_content = fallback_path.read_text("UTF-8")
+        if existing_content == content:
             print(f"✔️  {fallback_path} (already up to date)")
+            _new_files_written.append((fallback_path, original_path))
             return False
 
     if dry:
@@ -965,8 +1041,6 @@ def _write_fallback_file(
     fallback_path.write_text(content, "UTF-8", newline="\n")
     if executable and sys.platform != "win32":
         fallback_path.chmod(fallback_path.stat().st_mode | 0o111)
-    if fallback_path.suffix == ".py":
-        _python_files_to_format.append(fallback_path)
     print(f"✅ Created {fallback_path} (original customized by user)")
     _new_files_written.append((fallback_path, original_path))
     return True
@@ -1216,13 +1290,28 @@ def cmd_setup(args: argparse.Namespace) -> int:
     else:
         print(f"📦 Module: {module_name}")
 
+    module_dir = project_dir / module_name
+    scripts_dir = project_dir / "scripts"
+    fastapi_vue_scripts = scripts_dir / "fastapi-vue"
+
+    # Check if project already has a CLI entrypoint in pyproject.toml
+    existing_cli_module = _find_existing_cli_module_path(project_dir, module_name)
+
+    # Determine main module path for DEVMODE import
+    main_module_path = existing_cli_module or f"{module_name}.__main__"
+    if existing_cli_module:
+        print(f"ℹ️  Using existing CLI: {existing_cli_module}")
+
+    # Resolve the CLI main module to a file path
+    main = project_dir / Path(*main_module_path.split(".")).with_suffix(".py")
+
     # Determine port configuration
     # Priority: --ports argument > existing project values > defaults
     if args.ports:
         default_port, vite_port, dev_port = parse_ports(args.ports)
         ports_note = "(--ports)"
     else:
-        existing_ports = extract_existing_ports(project_dir)
+        existing_ports = extract_existing_ports(project_dir, main)
         if existing_ports:
             default_port, vite_port, dev_port = existing_ports
             ports_note = "(kept for upgrade)"
@@ -1237,6 +1326,11 @@ def cmd_setup(args: argparse.Namespace) -> int:
     # Title for templates
     project_title = module_name.replace("_", " ").title()
 
+    # Find existing FastAPI app
+    app_info = (
+        find_fastapi_app(module_dir, project_dir) if module_dir.exists() else None
+    )
+
     # Template variables
     tpl_vars = {
         "MODULE_NAME": module_name,
@@ -1246,28 +1340,22 @@ def cmd_setup(args: argparse.Namespace) -> int:
         "TEMPLATE_DEV_PORT": str(dev_port),
         "ENVPREFIX": module_name.upper(),
         "PROJECT_CLI": module_name,
+        "MAIN_MODULE": main_module_path,
     }
 
-    module_dir = project_dir / module_name
-    scripts_dir = project_dir / "scripts"
-    fastapi_vue_scripts = scripts_dir / "fastapi-vue"
-
-    # Find existing FastAPI app
-    app_info = (
-        find_fastapi_app(module_dir, project_dir) if module_dir.exists() else None
-    )
-
     if app_info:
         app_file, app_var = app_info
         print(f"📍 Found FastAPI app: {app_var} in {app_file.name}")
         tpl_vars["APP_VAR"] = app_var
-        tpl_vars["APP_MODULE"] = app_file.stem
+        # Dotted module path relative to project dir (e.g. "paskia.fastapi.mainapp")
+        app_module = ".".join(app_file.relative_to(project_dir).with_suffix("").parts)
+        tpl_vars["APP_MODULE"] = app_module
     else:
         print("📍 No existing FastAPI app found, will create new one")
         app_file = None
         app_var = "app"
         tpl_vars["APP_VAR"] = app_var
-        tpl_vars["APP_MODULE"] = "app"
+        tpl_vars["APP_MODULE"] = f"{module_name}.app"
 
     # Create directories
     if not dry:
@@ -1320,7 +1408,7 @@ def cmd_setup(args: argparse.Namespace) -> int:
     # === Handle app module ===
     if app_file:
         # Existing app: patch with import, route, and try to patch lifespan
-        patch_app_file(app_file, module_name, app_var, dry=dry)
+        patch_app_file(app_file, main_module_path, app_var, dry=dry)
     else:
         # No app: create full app.py
         # Create __init__.py if missing
@@ -1337,14 +1425,16 @@ def cmd_setup(args: argparse.Namespace) -> int:
         write_file(app_file_path, content, overwrite=False, dry=dry)
 
     # === Handle __main__.py ===
-    main_file = module_dir / "__main__.py"
+    if existing_cli_module:
+        # Existing CLI entrypoint - write .new.py beside the existing main module
+        main_fallback = main.with_suffix(".new.py")
+    else:
         main_fallback = module_dir / "__main__.new.py"
+
+    main_file = module_dir / "__main__.py"
     template = load_template("backend/__main__.py")
     main_content = render_template(template, **tpl_vars)
 
-    # Check if project already has a CLI entrypoint in pyproject.toml
-    existing_cli = _find_existing_cli_entrypoint(project_dir, module_name)
-
     if main_file.exists():
         # File exists: update if it has the auto-upgrade marker, otherwise use fallback
         write_file(
@@ -1354,7 +1444,7 @@ def cmd_setup(args: argparse.Namespace) -> int:
             dry=dry,
             fallback_path=main_fallback,
         )
-    elif not existing_cli:
+    elif not existing_cli_module:
         # No file and no existing entrypoint: create new __main__.py
         write_file(
             main_file,
@@ -1363,8 +1453,29 @@ def cmd_setup(args: argparse.Namespace) -> int:
             dry=dry,
         )
     else:
-        # No file but has existing entrypoint - don't create (user has custom CLI setup)
+        # Existing CLI entrypoint: write our template as .new.py beside the existing module
-        print(f"ℹ️  Skipping __main__.py (package already has CLI: {existing_cli})")
+        # and also patch the existing module with DEVMODE if needed
+        _write_fallback_file(
+            main,
+            main_fallback,
+            main_content,
+            dry=dry,
+            executable=False,
+        )
+        if main.exists():
+            content = main.read_text("UTF-8")
+            if "DEVMODE" not in content:
+                new_content = _add_devmode_to_main(content)
+                new_file = main.with_suffix(".new.py")
+                _write_fallback_file(
+                    main,
+                    new_file,
+                    new_content,
+                    dry=dry,
+                    executable=False,
+                )
+        else:
+            print(f"⚠️  Existing CLI main module {main} not found")
 
     # === Update vite.config.js/ts ===
     frontend_dir = project_dir / "frontend"
@@ -1440,7 +1551,6 @@ def cmd_setup(args: argparse.Namespace) -> int:
         print("✅ Created .gitignore")
 
     # === Add dependencies using uv ===
-    ruff_sort_imports(_python_files_to_format, dry=dry)
     if dry:
         print("📦 Would add: fastapi[standard], fastapi-vue, httpx (dev only)")
     else:
@@ -1463,12 +1573,16 @@ def cmd_setup(args: argparse.Namespace) -> int:
     # Show merge note if any .new.py files were written
     if _new_files_written:
         print()
-        print(
+        print("⚠️  Some files could not be auto-upgraded because you customized them.")
-            "⚠️  Note: Some files could not be auto-upgraded because you customized them."
-        )
         print("   Please manually merge the following files:")
         for new_file, original_file in _new_files_written:
-            print(f"     • {new_file.name} → {original_file.name}")
+            try:
+                new_rel = new_file.relative_to(project_dir)
+                orig_rel = original_file.relative_to(project_dir)
+            except ValueError:
+                new_rel = new_file.name
+                orig_rel = original_file.name
+            print(f"     • {new_rel} → {orig_rel}")
         print()
         # Clear the list for potential subsequent runs
         _new_files_written.clear()

template/backend/__main__.py

@@ -5,7 +5,7 @@ import os
 from fastapi_vue import server
 
 DEFAULT_PORT = TEMPLATE_DEFAULT_PORT
-DEVMODE = bool(os.getenv("ENVPREFIX_DEV") == "1")
+DEVMODE = os.getenv("ENVPREFIX_DEV") == "1"
 
 
 def main():
@@ -17,12 +17,12 @@ def main():
         help=(f"Endpoint (default: localhost:{DEFAULT_PORT})."),
     )
     args = parser.parse_args()
-    dev = {"reload": True, "reload_dirs": ["MODULE_NAME"]}
+    dev = {"reload": True, "reload_dirs": ["paskia"]} if DEVMODE else {}
     server.run(
-        "MODULE_NAME.APP_MODULE:APP_VAR",
+        "APP_MODULE:APP_VAR",
         listen=args.listen,
         default_port=DEFAULT_PORT,
-        **(dev if DEVMODE else {}),
+        **dev,
     )
 
 

template/backend/app.py

@@ -3,7 +3,7 @@ from pathlib import Path
 
 from fastapi import FastAPI
 from fastapi_vue import Frontend
-from MODULE_NAME.__main__ import DEVMODE
+from MAIN_MODULE import DEVMODE
 
 # Vue Frontend static files
 frontend = Frontend(Path(__file__).with_name("frontend-build"))

template/frontend/vite-plugin-fastapi.js

@@ -11,7 +11,7 @@
  */
 
 export default function fastapiVue({ paths = ["/api"] } = {}) {
-  const backendUrl = process.env.ENVPREFIX_BACKEND_URL || "http://localhost:TEMPLATE_DEFAULT_PORT"
+  const backendUrl = process.env.ENVPREFIX_BACKEND_URL || "http://localhost:TEMPLATE_DEV_PORT"
 
   // Build proxy configuration for each path
   const proxy = {}

template/scripts/devserver.py

@@ -56,13 +56,14 @@ def main():
         epilog=HELP_EPILOG,
     )
     parser.add_argument(
-        "-l", "--listen",
+        "-l",
-        metavar="host:port",
+        "--listen",
+        metavar="addr",
         help=f"Vite (default: localhost:{DEFAULT_VITE_PORT})",
     )
     parser.add_argument(
         "--backend",
-        metavar="host:port",
+        metavar="addr",
         help=f"FastAPI (default: localhost:{DEFAULT_DEV_PORT})",
     )
     args, extra_args = parser.parse_known_args()
@@ -71,7 +72,7 @@ def main():
 
 
 HELP_EPILOG = """
-  scripts/devserver.py [args to PROJECT_CLI]
+  Other options are forwarded to PROJECT_CLI [args]
 
   JS_RUNTIME environment variable can be used to select the JS runtime:
   npm, deno, bun, or full path to the runtime executable (node maps to npm).