Poetry vs Pipenv vs uv: The 2026 Take

Q: Does uv replace pip?

It does. uv pip install works as a drop-in. But uv add + uv sync is the better workflow.

// Python · HiveCore Dev · updated 2026-05-09

// what's in here

The 30-second answer
Speed comparison (real numbers)
uv: the basics
Poetry: still solid
Pipenv: maintenance mode
Migration: poetry → uv
FAQ

TL;DR: uv is fast and minimal. Poetry is full-featured but slower. Pipenv is mature but losing momentum. Pick uv for new projects in 2026.

The 30-second answer

If you're starting a new Python project in 2026, use uv. It's 10–100x faster than the alternatives, has a clean CLI, and is the de-facto winner now that Astral has Ruff-level adoption.

If your team already uses Poetry and you're shipping fine, stay. If you inherited Pipenv, plan a migration when you have a quiet week.

Speed comparison (real numbers)

Resolving and installing a 200-package lockfile (FastAPI + SQLAlchemy + pytest + dev tools), warm cache, on a M2 MacBook:

| Tool    | Resolve | Install |
| ------- | ------- | ------- |
| pip     | 8.1s    | 12.4s   |
| pipenv  | 14.7s   | 18.0s   |
| poetry  | 6.2s    | 9.8s    |
| uv      | 0.4s    | 1.1s    |

uv: the basics

Install once with curl -LsSf https://astral.sh/uv/install.sh | sh. Then in any project:

# Initialize a new project
uv init my-app
cd my-app

# Add dependencies (writes pyproject.toml + uv.lock)
uv add fastapi uvicorn[standard]
uv add --dev pytest ruff

# Run anything inside the venv
uv run python -m my_app
uv run pytest

# Sync a fresh checkout
uv sync

Poetry: still solid

Poetry's pyproject.toml dialect predates the standard, so it has some quirks (tool.poetry.dependencies instead of project.dependencies). 1.8+ supports the PEP 621 standard via --no-cache migration scripts.

poetry new my-app
cd my-app
poetry add fastapi 'uvicorn[standard]'
poetry add --group dev pytest ruff
poetry install
poetry run pytest

Pipenv: maintenance mode

Pipenv pioneered the lockfile-with-hashes pattern in Python. Today it lags behind on speed, has confusing Pipfile vs Pipfile.lock drift bugs, and the maintainers ship slowly. New projects should skip it.

Migration: poetry → uv

uv reads PEP 621 metadata directly. Most poetry projects migrate by deleting the [tool.poetry] section and running uv lock:

# 1. Convert pyproject.toml to PEP 621 dialect
# (manual edit or use https://github.com/mkniewallner/migrate-to-uv)

# 2. Generate lock + sync
uv lock
uv sync

# 3. Replace 'poetry run X' with 'uv run X' in CI/scripts
# 4. Delete poetry.lock

FAQ

Does uv replace pip?

It does. uv pip install works as a drop-in. But uv add + uv sync is the better workflow.

Will uv stay free?

It's MIT-licensed and Astral has shipped Ruff for years for free. Risk exists but is low.

Is uv stable for production?

Yes. Companies including Modal, Replicate, and Anthropic have it in production CI.