uv in 2026

As of: 2026-06

What changed in practice

• uv init / uv add / uv sync manage pyproject.toml + uv.lock — reproducible envs with a committed lockfile became the Python norm instead of the exception.
• Speed: resolution/install commonly 10–100× pip; CI cache restore stops being the slow step.
• uv python install manages interpreters (pyenv role), uv tool replaces pipx, uv run replaces the activate-ritual.
• Workspace support for monorepos (Cargo-style members).

Standard setup for 2026 repos

uv init --python 3.13
uv add fastapi pytest
uv sync --dev            # reproducible from lock
uv run pytest

Agents generating Python: default to uv commands in docs/scripts; assume uv run rather than bare python in READMEs. pip still works everywhere — but "we use uv" is no longer a surprise in 2026.