The Radiant Light of UV

Wed, Apr 23, 2025

The Radiant Light of UV — A Python Package Manager

Ultraviolet (UV) light is a type of electromagnetic radiation with a wavelength shorter than visible light — and it’s not actually “radiant” to the eye, because it’s invisible.

But here, we’re talking about UV, the latest and lightning-fast package management system for Python.

Introducing UV — A Package Manager by ASTRAL

UV stands for Ultraviolet, a smart metaphor.

Just like UV rays are fast, powerful, and invisible — the UV package manager aims to bring that same spirit to Python development: fast, silent, and effortless.

• ⚡ Blazing Fast: UV is written in Rust and outperforms tools like pip and pip-tools.
• 🧼 Silent & Automated: Tasks like creating virtual environments and lockfiles are handled behind the scenes.
• 🔧 All-in-One: UV replaces fragmented tools like pip, pip-tools, virtualenv, and build.

A once-beloved package manager in Python was Poetry — poetically managing dependencies with structure and elegance. Developers appreciated its order.

But now, UV steps into the spotlight — fast, agile, and unassuming.

While Poetry carefully manages dependencies, UV, powered by Rust, does the job at lightning speed —
before you even realize it, your packages are installed and ready to go.

Behind UV — The Astral Team & The Birth of a Modern Tool

Astral is a creative and forward-thinking team in the Python ecosystem. They previously created PDM, a modern package manager based on PEP 582, which received great community feedback.

Through this experience, they encountered limitations in current tools like pip, pip-tools, virtualenv, and poetry.

They realized traditional tools were:

• Slow,
• Scattered (you had to combine multiple tools),
• Not always developer-friendly.

That’s why UV was born —
A modern, fast, and unified solution to transform how Python projects are managed.

🎯 UV’s Core Mission:

To be a single, modern tool for managing all aspects of Python projects, offering features like:

• 🚀 A complete replacement for pip, pip-tools, pipx, poetry, pyenv, twine, virtualenv, and more.
• ⚡ 10–100x faster than pip.
• 🗂️ Comprehensive project management with a universal lockfile.
• ❇️ Script execution with inline dependency metadata.
• 🐍 Python version installation and management.
• 🛠️ Running tools published as Python packages.
• 🔩 pip-compatible CLI for familiar usage with enhanced performance.
• 🏢 Support for scalable projects with Cargo-style workspaces.
• 💾 Disk-efficient with a global cache to avoid duplicate dependencies.
• ⏬ Installable without needing Rust or Python (via curl or pip).
• 🖥️ Cross-platform: macOS, Linux, and Windows support.

UV isn’t just a replacement for existing tools —
It’s a vision for a faster, simpler, more powerful future of Python packaging.

💡 Installing and Using UV

Installing UV is quick and easy. Depending on your OS, run one of the following:

For Windows

In PowerShell, run:

powershell -ExecutionPolicy ByPass -c "irm https://astral.sh/uv/install.ps1 | iex"

For macOS and Linux

Run this in your terminal using curl:

curl -LsSf https://astral.sh/uv/install.sh | sh

After installation, check the version to ensure everything’s working:

uv --version

To see all available commands:

uv --help

To view available Python versions:

uv python list

To install a specific version of Python (or latest if not specified):

uv python install 3.11.6

Activating the Virtual Environment

After setting up UV and choosing your Python version, activate the virtual environment.

uv venv

uv venv --python 3.11.6

Activating the Virtual Environment

After setting up UV and choosing your Python version, activate the virtual environment

• Linux/macOS:

source .venv/bin/activate

• Windows (CMD):

.venv\Scripts\activate.bat

Initializing a Project and Creating a Lockfile:

uv init

To install a package like FastAPI with standard extras:

uv add fastapi --extra standard

So, what about removing a package? Or what does this command do?

uv run fastapi dev

Maybe it’s time for you to try UV for yourself. Trust me — it’s one of the most satisfying Python package managers out there.

If you want to dive deeper into UV, make sure to check out the official documentation:

👉 https://docs.astral.sh/uv/

I personally learned the UV commands from the official website, and I hope my explanation has given you enough motivation to explore it further.

** Your turn to try it out.