v0.13.1

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Released on 2026-10-14.

Enhancements

• Ignore Requires-Python upper bounds in uv pip check and uv pip install --strict, consistent with resolution (#​22500)
• Support Linux SPARC by falling back when filesystem cloning and detailed cache accounting are unavailable (#​22463)
• Report missing trusted hashes in resolution errors (#​22241)

Python

• Add CPython 3.16.0a1 (#​22527)

Preview features

• Allow uv tool upgrade to upgrade installed tools when tool-install-locks is enabled (#​22498)
• Add preliminary support for parsing PEP 825 variant labels in wheel filenames with wheel-variants (#​22039)

Performance

• Reduce uv's binary size (#​22429, #​22430, #​22432)
• Speed up Simple API parsing (#​22429)
• Reduce package metadata parsing overhead (#​22239)

Bug fixes

• Prevent tool and managed Python uninstalls from deleting unrelated files beside their storage directories (#​22495)
• Restore support for source distributions containing hard links or full-length tar user or group names (#​22516, #​22522)
• Preserve device files and FIFOs used as uv pip compile or uv export output destinations (#​22496)
• Fix sys._base_executable detection for environments created from symlinked interpreters (#​22520)
• Prevent concurrent readers from observing partially written lockfiles, Python version files, or managed Python sysconfig files (#​22399, #​22402, #​22403)
• Serialize concurrent project commands that reach the same environment through real and symlinked paths (#​22390)
• Prevent installs, syncs, and environment creation from failing when they race with uv cache clean (#​22387)
• Prevent concurrent tool installations from corrupting an environment when the last tool is uninstalled (#​22391)
• Persist changed upgrade settings even when uv tool upgrade leaves the tool version unchanged (#​22499)
• Reuse environments with installed Git dependencies pinned to full commit hashes without resolving again (#​22464)

Documentation

• Explain how to select an emulated Python interpreter on Windows ARM64 when native wheels are unavailable (#​22424)
• Fix the .netrc format documentation link (#​22514)

Other changes

• Publish Python 3.15-based uv Docker images under stable tags (#​22503)

v0.13.0

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Released on 2026-10-09.

uv 0.13.0 makes Python 3.15 the default stable Python version. We've also included several breaking changes to improve correctness, performance, and compatibility, described below.

We expect most users to be able to upgrade without making changes.

While not a breaking change, this release also updates the format of many of uv's cache entries to improve performance. uv may download or rebuild dependencies after upgrading, because some cached entries from earlier versions cannot be reused. Multiple versions of uv can still safely share the same cache directory.

There are no breaking changes to the configuration of the uv build backend. If your [build-system] table includes an upper bound on uv_build, update it to allow uv_build 0.13, e.g., uv_build>=0.13.0,<0.14.

Breaking changes

• Use Python 3.15 as the default stable version

  The default stable Python version has changed from 3.14 to 3.15. This affects Python downloads when no version is requested or pinned, e.g., when running uv python install.

  uv continues to use compatible Python installations that are already present. For example, uv venv can still use an installed Python 3.14. If no suitable interpreter is installed and automatic downloads are enabled, commands such as uv venv and uvx python can now download Python 3.15.

  You can opt out of this behavior by requesting Python 3.14 explicitly, e.g., uv venv --python 3.14. For projects, use uv python pin 3.14 to record the version in .python-version.

• Honor --require-hashes in included constraints files (#​22275)

  Previously, uv ignored --require-hashes in constraints files included with -c from a requirements file. Now, uv honors the directive and requires hashes for all requirements in the installation. Installs that previously succeeded can now fail if a requirement is missing a hash.

  You cannot opt out while the directive is present. Add the missing hashes to your requirements, or remove the --require-hashes directive from the included constraints file if hash checking is not intended.

• Prefer native Python on Windows ARM64 (#​22100)

  Previously, ARM64 builds of uv preferred emulated x86_64 Python installations because native wheel support was limited. Now, uv prefers native ARM64 (aarch64) interpreters across Python versions.

  This follows similar changes in CPython, the official Windows Python install manager, and GitHub's actions/setup-python.

  When a native interpreter is unavailable, uv continues to fall back to x86_64, then 32-bit x86.

  You can opt out of this behavior by setting UV_PYTHON_ARCH=x86_64 or requesting an explicit architecture, e.g., cpython-3.14-windows-x86_64. If you are using setup-uv, you can set python-arch: x86_64 instead.

• Reject editable requirements in included constraints files (#​22282)

  Previously, uv silently ignored editable (-e) requirements in constraints files included with -c from a requirements file. Now, uv rejects these requirements with an error, matching pip's behavior.

  You cannot opt out of this behavior. Move editable requirements to a requirements file passed with -r, or pass them directly with --editable, instead of including them in a constraints file.

• Omit the distutils startup patch on Python 3.10 and later (#​22096)

  Previously, uv installed _virtualenv.py and _virtualenv.pth into every new virtual environment to prevent distutils configuration from changing installation paths. Now, like virtualenv 21.6.0, uv omits these files on Python 3.10 and later, which already ignore the affected configuration keys. This reduces Python startup overhead. Python 3.9 and earlier retain the patch.

  You cannot opt out of this behavior. Existing virtual environments are not modified automatically. Recreate an environment with Python 3.10 or later to remove the patch.

  This stabilizes the no-distutils-patch preview feature.

• Treat requirement-file option values as single paths (#​22290)

  Previously, uv split values passed to --constraint, --override, --exclude, and --build-constraint on spaces, even when quoted. Now, each value is treated as a single path, allowing file paths containing spaces.

  You cannot opt out of this behavior. Repeat the option to provide multiple files. For example, replace -c "a.txt b.txt" with -c a.txt -c b.txt.

  Space-separated lists in UV_CONSTRAINT, UV_OVERRIDE, UV_EXCLUDE, and UV_BUILD_CONSTRAINT remain supported.

• Use tar-codec for tar archives by default (#​22094)

  Previously, uv used astral-tokio-tar to extract tar archives, build source distributions with uv_build, and read their metadata for uv publish. Now, uv uses tar-codec, which applies stricter validation when reading archives.

  uv may now reject archives containing hard links or unsupported tar extensions that previous versions accepted. Source distributions created by uv_build can also have different archive bytes and hashes.

  You can opt out of this behavior by setting UV_LEGACY_TAR_BACKEND=1.

  This stabilizes the tar-codec preview feature.

• Reject uv build --clear output directories that contain a build source
  (#​22276)

  Previously, uv build --clear could delete a project or input source distribution when the
  output directory contained the source. Now, uv rejects these output directories, including
  equivalent paths reached through symlinks, before clearing any build output.

  Select an output directory that does not contain any build sources, or omit --clear.

Python

• Add CPython 3.15.0 (#​22400)

Preview features

• Require hashes for build dependencies, including transitive dependencies, with --require-build-hashes (#​21411)

Performance

• Speed up revalidation of cached HTTP responses by avoiding rewrites of unchanged payloads (#​22130)
• Reduce allocations when reading cached HTTP responses (#​22136)
• Reduce cache storage for HTTP policies and package records (#​22135, #​22133)
• Reduce allocations for cached source distribution revisions (#​22131)

Bug fixes

• Fix incorrect dependency resolution when reusing source metadata with different build settings (#​22404)
• Avoid overlong wheel cache lock filenames on Windows (#​22134)

v0.12.24

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Release Notes

Released on 2026-10-08.

Enhancements

• Remove orphaned temporary build environments with uv cache prune (#​22171)
• Accept PEP 508 marker operators directly before grouped expressions (#​22309)
• Reject malformed requirements-file options instead of partially parsing or ignoring them (#​22317)
• Show underlying filesystem and registry errors when managed Python uninstallation fails (#​22362)
• Identify the invalid source URL in Python mirror errors (#​22364)

Preview features

• Display preferred advisory IDs in uv audit reports, prioritizing PYSEC, GHSA, then CVE identifiers (#​22292)

Configuration

• Support custom installation mirrors for GraalPy (#​22269)
• Support custom installation mirrors for Pyodide (#​22271)
• Allow UV_NO_CACHE=false to override no-cache = true in configuration (#​22324)
• Report more precise error locations for invalid trusted-host ports and preview-feature list entries (#​22144)

Performance

• Speed up later commands after creating an environment by warming its interpreter cache (#​21304)
• Reduce code-signature verification work for ARM64 macOS releases with 16 KiB signature pages (#​22246)
• Enforce resource limits when parsing package indexes and --find-links pages with astral-html (#​22203)
• Reduce standalone uv-build executable size by 7.5% by omitting unused Zstandard support (#​22242)
• Reduce uv's binary size by about 232 KB by simplifying configuration deserialization (#​22144)
• Reduce Python download error formatting code size by sharing its formatter (#​22141)

Bug fixes

• Verify supplied hashes even when hash presence is disabled with --no-require-hashes or require-hashes = false (#​22369)
• Honor exact managed Python patch pins when creating script environments instead of following patch upgrades (#​22360)
• Prevent dependency overrides and constraints from activating optional dependencies when their extras are not selected (#​22237)
• Exclude optional dependencies from exports when their extras are activated only in incompatible environments (#​22234)
• Give explicit uv publish --trusted-publishing values precedence over configuration (#​22279)
• Allow UV_OFFLINE=false to override offline = true in configuration (#​22283)
• Allow UV_SYSTEM_CERTS=false to override system-certs = true in configuration (#​22291)
• Allow uv auth login over IPv6 loopback addresses (#​22306)
• Resolve GitHub dependencies whose Git references contain # or % characters (#​22281)
• Recognize existing Pyodide interpreters as satisfying Pyodide Python requests (#​22322)
• Preserve JSON output from uv version and uv self version with a single --quiet flag (#​22280)
• Preserve trailing spaces and tabs in passwords returned by subprocess keyrings (#​22284)
• Restore wheel incompatibility hints when WHEEL metadata contains multiple expanded Tag: rows (#​22235)
• Preserve Windows wheel-script rename errors unless a cross-drive copy fallback applies (#​22302)
• Prevent workspace-cache assertion failures after modifying a project at the workspace root (#​22236)
• Hide the ignored --keyring-provider option from uv auth help (#​19520)
• Report HTTP client setup failures directly when resolving unnamed uv tool requirements (#​22320)

Documentation

• Update Docker and AWS Lambda examples to cache dependency layers using frozen lockfiles without project manifests (#​22172)
• Fix stale links and descriptions in Rust crate documentation (#​22311, #​22361)
• Fix a typo in the required-environments documentation (#​22238)

Install uv 0.12.24

Install prebuilt binaries via shell script

curl --proto '=https' --tlsv1.2 -LsSf https://releases.astral.sh/github/uv/releases/download/0.12.24/uv-installer.sh | sh

Install prebuilt binaries via powershell script

powershell -ExecutionPolicy Bypass -c "irm https://releases.astral.sh/github/uv/releases/download/0.12.24/uv-installer.ps1 | iex"

Download uv 0.12.24

Verifying GitHub Artifact Attestations

The artifacts in this release have attestations generated with GitHub Artifact Attestations. These can be verified by using the GitHub CLI:

gh attestation verify <file-path of downloaded artifact> --repo astral-sh/uv

You can also download the attestation from GitHub and verify against that directly:

gh attestation verify <file-path of downloaded artifact> --bundle <file-path of downloaded attestation>

v0.12.23

Compare Source

Release Notes

Released on 2026-10-03.

Python

• Add CPython 3.15.0rc3 (#​22164)

Preview features

• Sync from uv.lock without a workspace manifest using uv sync --frozen with frozen-lockfile (#​22018)
• Export from uv.lock without a workspace manifest using uv export --frozen with frozen-lockfile (#​22007)
• Inspect dependency trees from uv.lock without a workspace manifest using uv tree --frozen with frozen-lockfile (#​22016)
• Inspect workspace metadata and optionally sync its environment from uv.lock without a workspace manifest using uv workspace metadata --frozen with frozen-lockfile (#​22017, #​22018)

Bug fixes

• Reject alternate sources for workspace members across conflicting dependency selections, avoiding lockfiles that cannot be installed (#​22153)
• Allow x86-64 Python interpreters running under emulation on Windows ARM64 to install compatible win_amd64 wheels instead of building from source (#​22099)

Install uv 0.12.23

Install prebuilt binaries via shell script

curl --proto '=https' --tlsv1.2 -LsSf https://releases.astral.sh/github/uv/releases/download/0.12.23/uv-installer.sh | sh

Install prebuilt binaries via powershell script

powershell -ExecutionPolicy Bypass -c "irm https://releases.astral.sh/github/uv/releases/download/0.12.23/uv-installer.ps1 | iex"

Download uv 0.12.23

Verifying GitHub Artifact Attestations

The artifacts in this release have attestations generated with GitHub Artifact Attestations. These can be verified by using the GitHub CLI:

gh attestation verify <file-path of downloaded artifact> --repo astral-sh/uv

You can also download the attestation from GitHub and verify against that directly:

gh attestation verify <file-path of downloaded artifact> --bundle <file-path of downloaded attestation>

v0.12.22

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Release Notes

Released on 2026-10-01.

Python

• Add CPython 3.10.22, 3.11.17, 3.12.15, 3.13.16, and 3.14.8 (#​22147)

Enhancements

• Accept uppercase release suffixes in wheel platform tags (#​22113)
• Record workspace-member default groups in lockfiles (#​22010, #​22103)
• Record workspace-member dependency-group Python requirements in lockfiles (#​22044, #​22103)
• Record default groups for non-project workspace roots in lockfiles (#​22104)
• Record dependency-group Python requirements for non-project workspace roots in lockfiles (#​22104)
• Format URLs and paths consistently in CLI messages (#​21937)
• Hide the unsupported --offline option from uv publish help (#​22124)

Preview features

• Honor --no-default-groups in uv audit (#​22090)
• Report a clear error when uv audit or uv tool audit runs offline and hide the unsupported option from help (#​22114)

Configuration

• Add UV_PYTHON_ARCH to select an interpreter architecture independently of its Python version (#​22098)

Performance

• Reduce uv's binary size by compressing embedded Python download metadata (#​22126)

Bug fixes

• Verify unchanged requirements against existing lockfile hashes when relocking (#​22083)
• Honor dependency-group Python requirements at non-project workspace roots (#​22101)
• Use each selected workspace member's recorded default groups during frozen sync (#​22015)
• Avoid false entry-point warnings for required workspace members (#​22112)

Other changes

• Raise the minimum supported Rust version for building uv to 1.97 and update the toolchain to Rust 1.99 (#​22121)

Install uv 0.12.22

Install prebuilt binaries via shell script

curl --proto '=https' --tlsv1.2 -LsSf https://releases.astral.sh/github/uv/releases/download/0.12.22/uv-installer.sh | sh

Install prebuilt binaries via powershell script

powershell -ExecutionPolicy Bypass -c "irm https://releases.astral.sh/github/uv/releases/download/0.12.22/uv-installer.ps1 | iex"

Download uv 0.12.22

Verifying GitHub Artifact Attestations

The artifacts in this release have attestations generated with GitHub Artifact Attestations. These can be verified by using the GitHub CLI:

gh attestation verify <file-path of downloaded artifact> --repo astral-sh/uv

You can also download the attestation from GitHub and verify against that directly:

gh attestation verify <file-path of downloaded artifact> --bundle <file-path of downloaded attestation>

v0.12.21

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Release Notes

Released on 2026-09-29.

Python

• Update CPython to use OpenSSL 3.5.9 (#​22076)

Enhancements

• Omit empty [manifest] tables from lockfiles that contain only manifest subtables (#​22070)

Preview features

• Omit redundant runtime constraints from uv.lock, including those involving pre-releases, with the resolution-inputs preview feature (#​22004, #​22068)

Bug fixes

• Prevent uv python pin --rm from removing a global .python-versions file without --global (#​21992)
• Fix installed-package checks incorrectly reporting post-releases as incompatible with exclusive lower bounds on pre-releases (#​22049)

Install uv 0.12.21

Install prebuilt binaries via shell script

curl --proto '=https' --tlsv1.2 -LsSf https://releases.astral.sh/github/uv/releases/download/0.12.21/uv-installer.sh | sh

Install prebuilt binaries via powershell script

powershell -ExecutionPolicy Bypass -c "irm https://releases.astral.sh/github/uv/releases/download/0.12.21/uv-installer.ps1 | iex"

Download uv 0.12.21

Verifying GitHub Artifact Attestations

The artifacts in this release have attestations generated with GitHub Artifact Attestations. These can be verified by using the GitHub CLI:

gh attestation verify <file-path of downloaded artifact> --repo astral-sh/uv

You can also download the attestation from GitHub and verify against that directly:

gh attestation verify <file-path of downloaded artifact> --bundle <file-path of downloaded attestation>

v0.12.20

Compare Source

Release Notes

Released on 2026-09-28.

Enhancements

• Reuse lockfiles when dependency declarations are semantically equivalent (#​21951)
• Preserve second-line encoding declarations when installing wheel scripts with CRLF shebangs (#​21990)

Preview features

• Write normalized requirement declarations with the lockfile-normalization preview feature (#​21951)
• Honor synthetic default groups when installing or syncing from pylock.toml (#​22003)
• Resolve local paths in exported pylock.toml files relative to the output file (#​22042)
• Install each package only once when repeated tool-install-locks requirements resolve to the same package (#​22000)
• Reuse lock-without-metadata lockfiles for conflicting groups with distinct base and extra requirement specifiers (#​22055)
• Use consistent root-package paths in uv workspace metadata and uv tree --format json output (#​22050)

Configuration

• Continue searching XDG_CONFIG_DIRS after empty entries (#​21987)

Performance

• Restore the previous HTTP cache-write scheduling while investigating severe cache-revalidation stalls on ext4 filesystems (#​22051)

Bug fixes

• Apply hash constraints to every repeated requirement under --require-hashes and --verify-hashes (#​21996)
• Allow metadata builds for first-party workspace projects under --no-build (#​21988)
• Honor project exclusion flags with --all-packages, including --no-install-project and --no-emit-project (#​21994)
• Restore pyproject.toml if uv upgrade fails or is interrupted (#​21983)
• Generate working Nushell activation scripts for relocatable virtual environments (#​21979)
• Prevent commands from running and changing state after displaying --show-settings (#​21989)
• Treat UTF-16 requirements files containing only a byte-order mark as empty (#​21991)
• Ignore unrecognized managed-Python implementation directories during uv python list and uv python upgrade instead of panicking (#​22033)
• Avoid panics and incorrect rewriting when managed Python sysconfig paths merely start with /install (#​22036)
• Report whitespace-only non-ASCII requirements as invalid instead of panicking (#​22035)
• Avoid a resolver panic when trace logging an always-false constraint (#​22034)

Install uv 0.12.20

Install prebuilt binaries via shell script

curl --proto '=https' --tlsv1.2 -LsSf https://releases.astral.sh/github/uv/releases/download/0.12.20/uv-installer.sh | sh

Install prebuilt binaries via powershell script

powershell -ExecutionPolicy Bypass -c "irm https://releases.astral.sh/github/uv/releases/download/0.12.20/uv-installer.ps1 | iex"

Download uv 0.12.20

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