Python Project Skill Modern Python project development using uv package manager and Flask for web components. Quick Start New Project with uv

Initialize new project

uv init my-project cd my-project

Add dependencies

uv add flask pytest ruff mypy

Run application

uv run python app.py

Run with Flask

uv run flask run --debug Package Manager: uv Use uv (astral-sh/uv) for all Python package management. It replaces pip, poetry, pyenv, and virtualenv. Common Commands

Project management

uv init < name

Initialize project

uv add < package

Add dependency

uv remove < package

Remove dependency

uv sync

Sync dependencies from lockfile

uv lock

Generate lockfile

Running

uv run < command

Run in project environment

uv run python script.py

Run Python script

uv run pytest

Run tests

Tools (like pipx)

uvx < tool

Run tool in ephemeral env

uv tool install < tool

Install tool globally

Python versions

uv python install 3.12

Install Python version

uv python pin 3.12

Pin version for project

Web Framework: Flask Use Flask for web applications - lightweight WSGI micro-framework. Minimal Flask App

app.py

from flask import Flask , render_template , request , jsonify app = Flask ( name ) @app . route ( "/" ) def index ( ) : return render_template ( "index.html" ) @app . route ( "/api/data" , methods = [ "GET" , "POST" ] ) def api_data ( ) : if request . method == "POST" : data = request . get_json ( ) return jsonify ( { "status" : "ok" , "received" : data } ) return jsonify ( { "message" : "Hello, API!" } ) if name == "main" : app . run ( debug = True ) Flask Project Structure my_flask_app/ ├── app.py # Application entry ├── pyproject.toml # uv project config ├── static/ # CSS, JS, images │ ├── css/ │ └── js/ ├── templates/ # Jinja2 templates │ ├── base.html │ └── index.html └── tests/ └── test_app.py Run Flask

Development

uv run flask run --debug

With specific host/port

uv run flask run --host = 0.0 .0.0 --port = 8080 Project Configuration pyproject.toml [ project ] name = "my-project" version = "0.1.0" description = "Project description" requires-python = ">=3.11" dependencies = [ "flask>=3.0" , ] [ project.optional-dependencies ] dev = [ "pytest>=8.0" , "ruff>=0.5" , "mypy>=1.10" , ] [ tool.ruff ] line-length = 88 target-version = "py311" [ tool.ruff.lint ] select = [ "E" , "F" , "I" , "UP" ] [ tool.mypy ] python_version = "3.11" strict = true [ tool.pytest.ini_options ] testpaths = [ "tests" ] Code Quality

Linting and formatting with ruff

uv run ruff check .

Check for issues

uv run ruff check . --fix

Auto-fix issues

uv run ruff format .

Format code

Type checking

uv run mypy .

Testing

uv run pytest uv run pytest -v --cov = src Scripts scripts/init-project.sh - Initialize new Python project with standard structure scripts/setup-flask.sh - Set up Flask application boilerplate References See references/uv-commands.md for complete uv reference See references/flask-patterns.md for Flask best practices