# macOS/Linux
curl -LsSf https://astral.sh/uv/install.sh | sh
 
# Windows (PowerShell)
powershell -c "irm https://astral.sh/uv/install.ps1 | iex"
 
# Using pip (if you already have Python)
pip install uv
 
# Using Homebrew (macOS)
brew install uv
 
# Using cargo (if you have Rust)
cargo install --git https://github.com/astral-sh/uv uv

uv --version
# uv 0.x.x

# Create new project with virtual environment
uv init my-project
cd my-project
 
# Or create in current directory
uv init .
 
# Initialize creates:
# - .python-version (Python version)
# - pyproject.toml (project config)
# - README.md
# - .gitignore

# Install packages (creates venv if needed)
uv add requests pandas
 
# Install dev dependencies
uv add --dev pytest black ruff
 
# Install from requirements.txt
uv pip install -r requirements.txt
 
# Install from pyproject.toml
uv sync

# Create virtual environment with uv
uv venv
 
# Create with specific Python version
uv venv --python 3.12
 
# Create with custom name
uv venv my-env
 
# Create with system site packages
uv venv --system-site-packages
 
# Specify location
uv venv /path/to/venv

# Linux/macOS
source .venv/bin/activate
 
# Windows (Command Prompt)
.venv\Scripts\activate.bat
 
# Windows (PowerShell)
.venv\Scripts\Activate.ps1
 
# Or use uv run (no activation needed)
uv run python script.py
uv run pytest

# Run Python script (auto-activates venv)
uv run python app.py
 
# Run installed CLI tool
uv run black .
uv run pytest
 
# Run with specific Python version
uv run --python 3.11 python script.py
 
# Pass arguments
uv run python script.py --arg value

# Add package (adds to pyproject.toml)
uv add requests
 
# Add with version constraint
uv add "django>=4.0,<5.0"
 
# Add multiple packages
uv add numpy pandas matplotlib
 
# Add dev dependency
uv add --dev pytest pytest-cov
 
# Add optional dependency group
uv add --optional docs sphinx
 
# Add from git
uv add git+https://github.com/user/repo.git
 
# Add from git with specific ref
uv add git+https://github.com/user/repo.git@v1.0.0
 
# Add from local path
uv add ./local-package
 
# Add editable local package
uv add -e ./local-package

# Remove package
uv remove requests
 
# Remove dev dependency
uv remove --dev pytest
 
# Remove multiple packages
uv remove numpy pandas matplotlib

# Upgrade specific package
uv add --upgrade requests
 
# Upgrade all packages
uv sync --upgrade
 
# Upgrade package to latest
uv add --upgrade requests
 
# Show what would be upgraded
uv tree --outdated

# Generate uv.lock file
uv lock
 
# Update lock file
uv lock --upgrade
 
# Lock without installing
uv lock --no-install
 
# Lock specific package
uv lock --upgrade-package requests

# Install Python version
uv python install 3.12
 
# Install multiple versions
uv python install 3.11 3.12 3.13
 
# Install latest version
uv python install
 
# List installed versions
uv python list
 
# Find available versions
uv python list --all-versions

# Set Python version for project
uv python pin 3.12
 
# This creates/updates .python-version file
 
# Use specific Python version for command
uv --python 3.11 run python script.py
 
# Create venv with specific version
uv venv --python 3.12

[project]
name = "my-project"
version = "0.1.0"
description = "My awesome project"
readme = "README.md"
requires-python = ">=3.8"
dependencies = [
    "requests>=2.31.0",
    "pydantic>=2.0.0",
    "click>=8.1.0",
]
 
[project.optional-dependencies]
dev = [
    "pytest>=7.4.0",
    "pytest-cov>=4.1.0",
    "black>=23.0.0",
    "ruff>=0.1.0",
    "mypy>=1.5.0",
]
docs = [
    "sphinx>=7.0.0",
    "sphinx-rtd-theme>=1.3.0",
]
 
[build-system]
requires = ["hatchling"]
build-backend = "hatchling.build"
 
[tool.uv]
dev-dependencies = [
    # Additional dev dependencies managed by uv
]
 
[tool.uv.sources]
# Custom package sources
my-package = { git = "https://github.com/user/repo.git" }

# Migrate from requirements.txt
uv add -r requirements.txt
 
# Migrate from poetry
# Already have pyproject.toml, just use:
uv sync
 
# Export to requirements.txt
uv pip freeze > requirements.txt
 
# Export with hashes
uv pip freeze --require-hashes > requirements.txt

# Project structure
# monorepo/
#   packages/
#     package-a/
#       pyproject.toml
#     package-b/
#       pyproject.toml
#   pyproject.toml (root)
 
# Root pyproject.toml
[tool.uv.workspace]
members = ["packages/*"]
 
# Install all workspace packages
uv sync
 
# Add workspace dependency
uv add --path ./packages/package-a

# .github/workflows/test.yml
name: Tests
 
on: [push, pull_request]
 
jobs:
  test:
    runs-on: ubuntu-latest
 
    steps:
      - uses: actions/checkout@v4
 
      - name: Install uv
        uses: astral-sh/setup-uv@v2
        with:
          enable-cache: true
 
      - name: Set up Python
        run: uv python install 3.12
 
      - name: Install dependencies
        run: uv sync --all-extras --dev
 
      - name: Run tests
        run: uv run pytest
 
      - name: Run linting
        run: |
          uv run ruff check .
          uv run black --check .

# Dockerfile
FROM python:3.12-slim
 
# Install uv
COPY --from=ghcr.io/astral-sh/uv:latest /uv /usr/local/bin/uv
 
# Set working directory
WORKDIR /app
 
# Copy dependency files
COPY pyproject.toml uv.lock ./
 
# Install dependencies
RUN uv sync --frozen --no-dev
 
# Copy application code
COPY . .
 
# Run application
CMD ["uv", "run", "python", "app.py"]

# Multi-stage Dockerfile
FROM python:3.12-slim AS builder
 
# Install uv
COPY --from=ghcr.io/astral-sh/uv:latest /uv /usr/local/bin/uv
 
WORKDIR /app
 
# Install dependencies to venv
COPY pyproject.toml uv.lock ./
RUN uv sync --frozen --no-dev --no-editable
 
# Runtime stage
FROM python:3.12-slim
 
WORKDIR /app
 
# Copy venv from builder
COPY --from=builder /app/.venv .venv
COPY . .
 
# Use venv
ENV PATH="/app/.venv/bin:$PATH"
 
CMD ["python", "app.py"]

# Create lockfile (uv.lock)
uv lock
 
# Install from lockfile (exact versions)
uv sync --frozen
 
# Update lockfile without installing
uv lock --no-install
 
# Upgrade specific package in lock
uv lock --upgrade-package requests
 
# Check if lockfile is up to date
uv lock --check
 
# Export lockfile to requirements.txt
uv export --format requirements-txt > requirements.txt
 
# Export with hashes for security
uv export --format requirements-txt --hash > requirements.txt

# UV automatically uses global cache at:
# Linux: ~/.cache/uv
# macOS: ~/Library/Caches/uv
# Windows: %LOCALAPPDATA%\uv\cache
 
# Clear cache
uv cache clean
 
# Check cache size
uv cache dir

# UV installs packages in parallel by default
 
# Control parallelism
uv pip install --jobs 4 package1 package2
 
# No parallel (sequential)
uv pip install --jobs 1 package

# Install from cache only (no network)
uv pip install --offline package
 
# Sync from lockfile offline
uv sync --frozen --offline

# pip
python -m venv .venv
source .venv/bin/activate
pip install requests pandas numpy
# ~30 seconds
 
# uv
uv venv
uv add requests pandas numpy
# ~2 seconds (10-15x faster)

# poetry
poetry init
poetry add requests pandas
poetry install
# ~20 seconds
 
# uv
uv init
uv add requests pandas
uv sync
# ~3 seconds (6-7x faster)

# pip-tools
pip-compile requirements.in
pip-sync requirements.txt
# ~15 seconds
 
# uv
uv lock
uv sync --frozen
# ~2 seconds (7-8x faster)

# Complete workflow
uv init my-project
cd my-project
 
# Set Python version
uv python pin 3.12
 
# Add dependencies
uv add fastapi uvicorn pydantic
 
# Add dev dependencies
uv add --dev pytest black ruff mypy
 
# Create structure
mkdir -p src/my_project tests
 
# Run tests
uv run pytest
 
# Format code
uv run black .
uv run ruff check .

# Clone repository
git clone https://github.com/user/project.git
cd project
 
# Install dependencies (creates venv automatically)
uv sync
 
# Install with dev dependencies
uv sync --all-extras
 
# Update dependencies
uv lock --upgrade
 
# Run application
uv run python app.py
 
# Run tests
uv run pytest
 
# Add new dependency
uv add new-package
 
# Commit updated files
git add pyproject.toml uv.lock
git commit -m "Add new-package dependency"

# .pre-commit-config.yaml
repos:
  - repo: local
    hooks:
      - id: uv-lock
        name: uv lock
        entry: uv lock
        language: system
        pass_filenames: false
 
      - id: ruff
        name: ruff
        entry: uv run ruff check --fix
        language: system
        types: [python]
 
      - id: black
        name: black
        entry: uv run black
        language: system
        types: [python]

// .vscode/settings.json
{
  "python.defaultInterpreterPath": "${workspaceFolder}/.venv/bin/python",
  "python.terminal.activateEnvironment": true,
  "python.testing.pytestEnabled": true,
  "python.testing.pytestArgs": ["-v"],
  "python.linting.enabled": true,
  "python.formatting.provider": "black",
  "[python]": {
    "editor.defaultFormatter": "ms-python.black-formatter",
    "editor.formatOnSave": true
  }
}

# Issue: uv not found
# Solution: Add to PATH or reinstall
echo 'export PATH="$HOME/.cargo/bin:$PATH"' >> ~/.bashrc
 
# Issue: Wrong Python version
# Solution: Pin version explicitly
uv python pin 3.12
uv venv --python 3.12
 
# Issue: Dependency conflict
# Solution: Check resolution
uv lock --verbose
 
# Issue: Cache issues
# Solution: Clear cache
uv cache clean
 
# Issue: Lockfile out of sync
# Solution: Regenerate
uv lock --upgrade

# Use frozen installs in CI
uv sync --frozen
 
# Use offline mode when possible
uv sync --offline
 
# Parallel operations (automatic)
# uv does this by default
 
# Reuse cache across environments
# uv shares cache globally
 
# Use lockfiles to skip resolution
uv sync --frozen  # skips resolution

# Before
python -m venv .venv
source .venv/bin/activate
pip install -r requirements.txt
 
# After
uv venv
uv pip install -r requirements.txt
# Or better:
uv init
uv add -r requirements.txt

# Before
poetry install
poetry add requests
 
# After
uv sync
uv add requests
 
# Keep existing pyproject.toml
# uv reads [project] and [tool.poetry] sections

# Before
pip-compile requirements.in
pip-sync requirements.txt
 
# After
uv lock
uv sync --frozen

# Project management
uv init [PATH]              # Initialize project
uv add PACKAGE              # Add dependency
uv remove PACKAGE           # Remove dependency
uv sync                     # Install dependencies
uv lock                     # Create/update lockfile
 
# Virtual environments
uv venv [PATH]              # Create venv
uv run COMMAND              # Run in venv
 
# Python management
uv python install VERSION   # Install Python
uv python list              # List installed Pythons
uv python pin VERSION       # Pin Python version
 
# Package installation (pip-compatible)
uv pip install PACKAGE      # Install package
uv pip uninstall PACKAGE    # Uninstall package
uv pip freeze               # List installed
uv pip list                 # List packages
 
# Utility
uv cache clean              # Clear cache
uv cache dir                # Show cache location
uv --version                # Show version