v0.8.0

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Since we released uv 0.7.0 in April, we've accumulated various changes that improve correctness and user experience, but could break some workflows. This release contains those changes; many have been marked as breaking out of an abundance of caution. We expect most users to be able to upgrade without making changes.

This release also includes the stabilization of a couple uv python install features, which have been available under preview since late last year.

Breaking changes

• Install Python executables into a directory on the PATH (#​14626)

  uv python install now installs a versioned Python executable (e.g., python3.13) into a directory on the PATH (e.g., ~/.local/bin) by default. This behavior has been available under the --preview flag since Oct 2024. This change should not be breaking unless it shadows a Python executable elsewhere on the PATH.

  To install unversioned executables, i.e., python3 and python, use the --default flag. The --default flag has also been in preview, but is not stabilized in this release.

  Note that these executables point to the base Python installation and only include the standard library. That means they will not include dependencies from your current project (use uv run python instead) and you cannot install packages into their environment (use uvx --with <package> python instead).

  As with tool installation, the target directory respects common variables like XDG_BIN_HOME and can be overridden with a UV_PYTHON_BIN_DIR variable.

  You can opt out of this behavior with uv python install --no-bin or UV_PYTHON_INSTALL_BIN=0.

  See the documentation on installing Python executables for more details.

• Register Python versions with the Windows registry (#​14625)

  uv python install now registers the installed Python version with the Windows Registry as specified by PEP 514. This allows using uv installed Python versions via the py launcher. This behavior has been available under the --preview flag since Jan 2025. This change should not be breaking, as using the uv Python versions with py requires explicit opt in.

  You can opt out of this behavior with uv python install --no-registry or UV_PYTHON_INSTALL_REGISTRY=0.

• Prompt before removing an existing directory in uv venv (#​14309)

  Previously, uv venv would remove an existing virtual environment without confirmation. While this is consistent with the behavior of project commands (e.g., uv sync), it's surprising to users that are using imperative workflows (i.e., uv pip). Now, uv venv will prompt for confirmation before removing an existing virtual environment. If not in an interactive context, uv will still remove the virtual environment for backwards compatibility. However, this behavior is likely to change in a future release.

  The behavior for other commands (e.g., uv sync) is unchanged.

  You can opt out of this behavior by setting UV_VENV_CLEAR=1 or passing the --clear flag.

• Validate that discovered interpreters meet the Python preference (#​7934)

  uv allows opting out of its managed Python versions with the --no-managed-python and python-preference options.

  Previously, uv would not enforce this option for Python interpreters discovered on the PATH. For example, if a symlink to a managed Python interpreter was created, uv would allow it to be used even if --no-managed-python was provided. Now, uv ignores Python interpreters that do not match the Python preference unless they are in an active virtual environment or are explicitly requested, e.g., with --python /path/to/python3.13.

  Similarly, uv would previously not invalidate existing project environments if they did not match the Python preference. Now, uv will invalidate and recreate project environments when the Python preference changes.

  You can opt out of this behavior by providing the explicit path to the Python interpreter providing --managed-python / --no-managed-python matching the interpreter you want.

• Install dependencies without build systems when they are path sources (#​14413)

  When working on a project, uv uses the presence of a build system to determine if it should be built and installed into the environment. However, when a project is a dependency of another project, it can be surprising for the dependency to be missing from the environment.

  Previously, uv would not build and install dependencies with path sources unless they declared a build system or set tool.uv.package = true. Now, dependencies with path sources are built and installed regardless of the presence of a build system. If a build system is not present, the setuptools.build_meta:__legacy__ backend will be used (per PEP 517).

  You can opt out of this behavior by setting package = false in the source declaration, e.g.:

  [tool.uv.sources]
  foo = { path = "./foo", package = false }

  Or, by setting tool.uv.package = false in the dependent pyproject.toml.

  See the documentation on virtual dependencies for details.

• Install dependencies without build systems when they are workspace members (#​14663)

  As described above for dependencies with path sources, uv previously would not build and install workspace members that did not declare a build system. Now, uv will build and install workspace members that are a dependency of another workspace member regardless of the presence of a build system. The behavior is unchanged for workspace members that are not included in the project.dependencies, project.optional-dependencies, or dependency-groups tables of another workspace member.

  You can opt out of this behavior by setting tool.uv.package = false in the workspace member's pyproject.toml.

  See the documentation on virtual dependencies for details.

• Bump --python-platform linux to manylinux_2_28 (#​14300)

  uv allows performing platform-specific resolution for explicit targets and provides short aliases, e.g., linux, for common targets.

  Previously, the default target for --python-platform linux was manylinux_2_17, which is compatible with most Linux distributions from 2014 or newer. We now default to manylinux_2_28, which is compatible with most Linux distributions from 2019 or newer. This change follows the lead of other tools, such as cibuildwheel, which changed their default to manylinux_2_28 in Mar 2025.

  This change only affects users requesting a specific target platform. Otherwise, uv detects the manylinux target from your local glibc version.

  You can opt out of this behavior by using --python-platform x86_64-manylinux_2_17 instead.

• Remove uv version fallback (#​14161)

  In Apr 2025, uv changed the uv version command to an interface for viewing and updating the version of the current project. However, when outside a project, uv version would continue to display uv's version for backwards compatibility. Now, when used outside of a project, uv version will fail.

  You cannot opt out of this behavior. Use uv self version instead.

• Require --global for removal of the global Python pin (#​14169)

  Previously, uv python pin --rm would allow you to remove the global Python pin without opt in. Now, uv requires the --global flag to remove the global Python pin.

  You cannot opt out of this behavior. Use the --global flag instead.

• Support conflicting editable settings across groups (#​14197)

  Previously, uv would always treat a package as editable if any requirement requested it as editable. However, this prevented users from declaring path sources that toggled the editable setting across dependency groups. Now, uv allows declaring different editable values for conflicting groups. However, if a project includes a path dependency twice, once with editable = true and once without any editable annotation, those are now considered conflicting, and uv will exit with an error.

  You cannot opt out of this behavior. Use consistent editable settings or mark groups as conflicting.

• Make uv_build the default build backend in uv init (#​14661)

  The uv build backend (uv_build) was stabilized in uv 0.7.19. Now, it is the default build backend for uv init --package and uv init --lib. Previously, hatchling was the default build backend. A build backend is still not used without opt-in in uv init, but we expect to change this in a future release.

  You can opt out of this behavior with uv init --build-backend hatchling.

• Set default UV_TOOL_BIN_DIR on Docker images (#​13391)

  Previously, UV_TOOL_BIN_DIR was not set in Docker images which meant that uv tool install did not install tools into a directory on the PATH without additional configuration. Now, UV_TOOL_BIN_DIR is set to /usr/local/bin in all Docker derived images.

  When the default image user is overridden (e.g. USER <UID>) with a less privileged user, this may cause uv tool install to fail.

  You can opt out of this behavior by setting an alternative UV_TOOL_BIN_DIR.

• Update --check to return an exit code of 1 (#​14167)

  uv uses an exit code of 1 to indicate a "successful failure" and an exit code of 2 to indicate an "error".

  Previously, uv lock --check and uv sync --check would exit with a code of 2 when the lockfile or environment were outdated. Now, uv will exit with a code of 1.

  You cannot opt out of this behavior.

• Use an ephemeral environment for uv run --with invocations (#​14447)

  When using uv run --with, uv layers the requirements requested using --with into another virtual environment and caches it. Previously, uv would invoke the Python interpreter in this layered environment. However, this allows poisoning the cached environment and introduces race conditions for concurrent invocations. Now, uv will layer another empty virtual environment on top of the cached environment and invoke the Python interpreter there. This should only cause breakage in cases where the environment is being inspected at runtime.

  You cannot opt out of this behavior.

• Restructure the uv venv command output and exit codes (#​14546)

  Previously, uv used miette to format the uv venv output. However, this was inconsistent with most of the uv CLI. Now, the output is a little different and the exit code has switched from 1 to 2 for some error cases.

  You cannot opt out of this behavior.

• Default to --workspace when adding subdirectories (#​14529)

  When using uv add to add a subdirectory in a workspace, uv now defaults to adding the target as a workspace member.

  You can opt out of this behavior by providing --no-workspace.

• Add missing validations for disallowed uv.toml fields (#​14322)

  uv does not allow some settings in the uv.toml. Previously, some settings were silently ignored when present in the uv.toml. Now, uv will error.

  You cannot opt out of this behavior. Use --no-config or remove the invalid settings.

Configuration

• Add support for toggling Python bin and registry install options via env vars (#​14662)

v0.7.22

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Python

• Upgrade GraalPy to 24.2.2

See the GraalPy release notes for more details.

Configuration

• Add UV_COMPILE_BYTECODE_TIMEOUT environment variable (#​14369)
• Allow users to override index cache-control headers (#​14620)
• Add UV_LIBC to override libc selection in multi-libc environment (#​14646)

Bug fixes

• Fix --all-arches when paired with --only-downloads (#​14629)
• Skip Windows Python interpreters that return a broken MSIX package code (#​14636)
• Warn on invalid uv.toml when provided via direct path (#​14653)
• Improve async signal safety in Windows exception handler (#​14619)

Documentation

• Mention the revision in the lockfile versioning doc (#​14634)
• Move "Conflicting dependencies" to the "Resolution" page (#​14633)
• Rename "Dependency specifiers" section to exclude PEP 508 reference (#​14631)
• Suggest uv cache clean prior to --reinstall (#​14659)

Preview features

• Make preview Python registration on Windows non-fatal (#​14614)
• Update preview installation of Python executables to be non-fatal (#​14612)
• Add uv python update-shell (#​14627)

v0.7.21

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Python

• Restore the SQLite fts4, fts5, rtree, and geopoly extensions on macOS and Linux

See the
python-build-standalone release notes
for more details.

Enhancements

• Add --python-platform to uv sync (#​14320)
• Support pre-releases in uv version --bump (#​13578)
• Add -w shorthand for --with (#​14530)
• Add an exception handler on Windows to display information on crash (#​14582)
• Add hint when Python downloads are disabled (#​14522)
• Add UV_HTTP_RETRIES to customize retry counts (#​14544)
• Follow leaf symlinks matched by globs in cache-key (#​13438)
• Support parent path components (..) in globs in cache-key (#​13469)
• Improve cache-key performance (#​13469)

Preview features

• Add uv sync --output-format json (#​13689)

Bug fixes

• Do not re-resolve with a new Python version in uv tool if it is incompatible with --python (#​14606)

Documentation

• Document how to nest dependency groups with include-group (#​14539)
• Fix repeated word in Pyodide doc (#​14554)
• Update CONTRIBUTING.md with instructions to format Markdown files via Docker (#​14246)
• Fix version number for setup-python (#​14533)

v0.7.20

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Python

• Add Python 3.14.0b4
• Add zstd support to Python 3.14 on Unix (it already was available on Windows)
• Add PyPy 7.3.20 (for Python 3.11.13)

See the PyPy and python-build-standalone release notes for more details.

Enhancements

• Add --workspace flag to uv add (#​14496)
• Add auto-detection for Intel GPUs (#​14386)
• Drop trailing arguments when writing shebangs (#​14519)
• Add debug message when skipping Python downloads (#​14509)
• Add support for declaring multiple modules in namespace packages (#​14460)

Bug fixes

• Revert normalization of trailing slashes on index URLs (#​14511)
• Fix forced resolution with all extras in uv version (#​14434)
• Fix handling of pre-releases in preferences (#​14498)
• Remove transparent variants in uv-extract to enable retries (#​14450)

Rust API

• Add method to get packages involved in a NoSolutionError (#​14457)
• Make ErrorTree for NoSolutionError public (#​14444)

Documentation

• Finish incomplete sentence in pip migration guide (#​14432)
• Remove cache-dependency-glob examples for setup-uv (#​14493)
• Remove uv pip sync suggestion with pyproject.toml (#​14510)
• Update documentation for GitHub to use setup-uv@v6 (#​14490)

v0.7.19

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The uv build backend is now stable, and considered ready for production use.

The uv build backend is a great choice for pure Python projects. It has reasonable defaults, with the goal of requiring zero configuration for most users, but provides flexible configuration to accommodate most Python project structures. It integrates tightly with uv, to improve messaging and user experience. It validates project metadata and structures, preventing common mistakes. And, finally, it's very fast — uv sync on a new project (from uv init) is 10-30x faster than with other build backends.

To use uv as a build backend in an existing project, add uv_build to the [build-system] section in your pyproject.toml:

[build-system]
requires = ["uv_build>=0.7.19,<0.8.0"]
build-backend = "uv_build"

In a future release, it will replace hatchling as the default in uv init. As before, uv will remain compatible with all standards-compliant build backends.

Python

• Add PGO distributions of Python for aarch64 Linux, which are more optimized for better performance

See the python-build-standalone release for more details.

Enhancements

• Ignore Python patch version for --universal pip compile (#​14405)
• Update the tilde version specifier warning to include more context (#​14335)
• Clarify behavior and hint on tool install when no executables are available (#​14423)

Bug fixes

• Make project and interpreter lock acquisition non-fatal (#​14404)
• Includes sys.prefix in cached environment keys to avoid --with collisions across projects (#​14403)

Documentation

• Add a migration guide from pip to uv projects (#​12382)

v0.7.18

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Python

• Added arm64 Windows Python 3.11, 3.12, 3.13, and 3.14

  These are not downloaded by default, since x86-64 Python has broader ecosystem support on Windows.
  However, they can be requested with cpython-<version>-windows-aarch64.

See the python-build-standalone release for more details.

Enhancements

• Keep track of retries in ManagedPythonDownload::fetch_with_retry (#​14378)
• Reuse build (virtual) environments across resolution and installation (#​14338)
• Improve trace message for cached Python interpreter query (#​14328)
• Use parsed URLs for conflicting URL error message (#​14380)

Preview features

• Ignore invalid build backend settings when not building (#​14372)

Bug fixes

• Fix equals-star and tilde-equals with python_version and python_full_version (#​14271)
• Include the canonical path in the interpreter query cache key (#​14331)
• Only drop build directories on program exit (#​14304)
• Error instead of panic on conflict between global and subcommand flags (#​14368)
• Consistently normalize trailing slashes on URLs with no path segments (#​14349)

Documentation

• Add instructions for publishing to JFrog's Artifactory (#​14253)
• Edits to the build backend documentation (#​14376)