An extremely fast Python package installer and resolver, written in Rust. Designed as a drop-in
replacement for common pip
and pip-tools
workflows.
Installing the Trio dependencies with a warm cache.
- ⚖️ Drop-in replacement for common
pip
,pip-tools
, andvirtualenv
commands. - ⚡️ 10-100x faster than
pip
andpip-tools
(pip-compile
andpip-sync
). - 💾 Disk-space efficient, with a global cache for dependency deduplication.
- 🐍 Installable via
curl
,pip
,pipx
, etc. uv is a static binary that can be installed without Rust or Python. - 🧪 Tested at-scale against the top 10,000 PyPI packages.
- 🖥️ Support for macOS, Linux, and Windows.
- 🧰 Advanced features such as dependency version overrides and alternative resolution strategies.
⁉️ Best-in-class error messages with a conflict-tracking resolver.- 🤝 Support for a wide range of advanced
pip
features, including editable installs, Git dependencies, direct URL dependencies, local dependencies, constraints, source distributions, HTML and JSON indexes, and more.
uv is backed by Astral, the creators of Ruff.
Install uv with our standalone installers, or from PyPI:
# On macOS and Linux.
curl -LsSf https://astral.sh/uv/install.sh | sh
# On Windows.
powershell -c "irm https://astral.sh/uv/install.ps1 | iex"
# For a specific version.
curl -LsSf https://astral.sh/uv/0.2.21/install.sh | sh
powershell -c "irm https://astral.sh/uv/0.2.21/install.ps1 | iex"
# With pip.
pip install uv
# With pipx.
pipx install uv
# With Homebrew.
brew install uv
To create a virtual environment:
uv venv # Create a virtual environment at .venv.
To activate the virtual environment:
# On macOS and Linux.
source .venv/bin/activate
# On Windows.
.venv\Scripts\activate
To install a package into the virtual environment:
uv pip install flask # Install Flask.
uv pip install -r requirements.txt # Install from a requirements.txt file.
uv pip install -e . # Install the current project in editable mode.
uv pip install "package @ ." # Install the current project from disk.
uv pip install "flask[dotenv]" # Install Flask with "dotenv" extra.
To generate a set of locked dependencies:
uv pip compile requirements.in -o requirements.txt # Read a requirements.in file.
uv pip compile pyproject.toml -o requirements.txt # Read a pyproject.toml file.
uv pip compile setup.py -o requirements.txt # Read a setup.py file.
echo flask | uv pip compile - -o requirements.txt # Read from stdin.
uv pip freeze | uv pip compile - -o requirements.txt # Lock the current environment.
To sync a set of locked dependencies with the virtual environment:
uv pip sync requirements.txt # Install from a requirements.txt file.
uv's pip-install
and pip-compile
commands support many of the same command-line arguments
as existing tools, including -r requirements.txt
, -c constraints.txt
, -e .
(for editable
installs), --index-url
, and more.
While uv supports a large subset of the pip
interface, it does not support the entire feature set.
In some cases, those differences are intentional; in others, they're a result of uv's early stage of
development.
For details, see our pip
compatibility guide.
Like pip-compile
, uv generates a platform-specific requirements.txt
file (unlike, e.g.,
poetry
and pdm
, which generate platform-agnostic poetry.lock
and pdm.lock
files). As such,
uv's requirements.txt
files may not be portable across platforms and Python versions.
uv is an extremely fast Python package resolver and installer, designed as a drop-in
replacement for pip
, pip-tools
(pip-compile
and pip-sync
), and virtualenv
.
uv represents an intermediary goal in our pursuit of a "Cargo for Python": a comprehensive project and package manager that is extremely fast, reliable, and easy to use.
Think: a single binary that bootstraps your Python installation and gives you everything you need to
be productive with Python, bundling not only pip
, pip-tools
, and virtualenv
, but also pipx
,
tox
, poetry
, pyenv
, ruff
, and more.
Our goal is to evolve uv into such a tool.
In the meantime, though, the narrower pip-tools
scope allows us to solve the low-level problems
involved in building such a tool (like package installation) while shipping something immediately
useful with a minimal barrier to adoption.
uv itself does not depend on Python, but it does need to locate a Python environment to (1) install dependencies into the environment and (2) build source distributions.
When running pip sync
or pip install
, uv will search for a virtual environment in the
following order:
- An activated virtual environment based on the
VIRTUAL_ENV
environment variable. - An activated Conda environment based on the
CONDA_PREFIX
environment variable. - A virtual environment at
.venv
in the current directory, or in the nearest parent directory.
If no virtual environment is found, uv will prompt the user to create one in the current
directory via uv venv
.
When running pip compile
, uv does not require a virtual environment and will search for a
Python interpreter in the following order:
- An activated virtual environment based on the
VIRTUAL_ENV
environment variable. - An activated Conda environment based on the
CONDA_PREFIX
environment variable. - A virtual environment at
.venv
in the current directory, or in the nearest parent directory. - The Python interpreter available as
python3
on macOS and Linux, orpython.exe
on Windows.
If a --python-version
is provided to pip compile
(e.g., --python-version=3.7
), uv will
search for a Python interpreter matching that version in the following order:
- An activated virtual environment based on the
VIRTUAL_ENV
environment variable. - An activated Conda environment based on the
CONDA_PREFIX
environment variable. - A virtual environment at
.venv
in the current directory, or in the nearest parent directory. - The Python interpreter available as, e.g.,
python3.7
on macOS and Linux. - The Python interpreter available as
python3
on macOS and Linux, orpython.exe
on Windows. - On Windows, the Python interpreter returned by
py --list-paths
that matches the requested version.
Since uv has no dependency on Python, it can install into virtual environments other than
its own. For example, setting VIRTUAL_ENV=/path/to/venv
will cause uv to install into
/path/to/venv
, regardless of where uv is installed. Note that if VIRTUAL_ENV
is set to
a directory that is not a PEP 405 compliant
virtual environment, it will be ignored.
uv can also install into arbitrary, even non-virtual environments, with the --python
argument
provided to uv pip sync
or uv pip install
. For example, uv pip install --python=/path/to/python
will install into the environment linked to the /path/to/python
interpreter.
For convenience, uv pip install --system
will install into the system Python environment.
Using --system
is roughly equivalent to uv pip install --python=$(which python)
,
but note that executables that are linked to virtual environments will be skipped.
Although we generally recommend using virtual environments for dependency management,
--system
is appropriate in continuous integration and containerized environments.
The --system
flag is also used to opt in to mutating system environments. For example, the
the --python
argument can be used to request a Python version (e.g., --python 3.12
), and uv will
search for an interpreter that meets the request. If uv finds a system interpreter (e.g., /usr/lib/python3.12
),
then the --system
flag is required to allow modification of this non-virtual Python environment.
Without the --system
flag, uv will ignore any interpreters that are not in virtual environments.
Conversely, when the --system
flag is provided, uv will ignore any interpreters that are
in virtual environments.
Installing into system Python across platforms and distributions is notoriously difficult. uv
supports the common cases, but will not work in all cases. For example, installing into system
Python on Debian prior to Python 3.10 is unsupported due to the distribution's patching
of distutils
(but not sysconfig
).
While we always recommend the use of virtual environments, uv considers them to be required in
these non-standard environments.
If uv is installed in a Python environment, e.g., with pip
, it can still be used to modify
other environments. However, when invoked with python -m uv
, uv will default to using the parent
interpreter's environment. Invoking uv via Python adds startup overhead and is not recommended for
general usage.
uv supports persistent configuration at both the project- and user-level.
Specifically, uv will search for a pyproject.toml
or uv.toml
file in the current directory, or
in the nearest parent directory.
If a pyproject.toml
file is found, uv will read configuration from the [tool.uv.pip]
table.
For example, to set a persistent index URL, add the following to a pyproject.toml
:
[tool.uv.pip]
index-url = "https://test.pypi.org/simple"
(If there is no such table, the pyproject.toml
file will be ignored, and uv will continue searching in
the directory hierarchy.)
If a uv.toml
file is found, uv will read from the [pip]
table. For example:
[pip]
index-url = "https://test.pypi.org/simple"
uv will also discover user-level configuration at ~/.config/uv/uv.toml
(or
$XDG_CONFIG_HOME/uv/uv.toml
) on macOS and Linux, or %APPDATA%\uv\uv.toml
on Windows. User-level
configuration must use the uv.toml
format, rather than the pyproject.toml
format, as a
pyproject.toml
is intended to define a Python project.
If both project- and user-level configuration are found, the settings will be merged, with the project-level configuration taking precedence. Specifically, if a string, number, or boolean is present in both tables, the project-level value will be used, and the user-level value will be ignored. If an array is present in both tables, the arrays will be concatenated, with the project-level settings appearing earlier in the merged array.
Settings provided via environment variables take precedence over persistent configuration, and settings provided via the command line take precedence over both.
uv accepts a --isolated
command-line argument which, when provided, disables the discovery of any
persistent configuration.
uv also accepts a --config-file
command-line argument, which accepts a path to a uv.toml
to use
as the configuration file. When provided, this file will be used in place of any discovered
configuration files (e.g., user-level configuration will be ignored).
uv allows packages to be installed from Git and supports the following schemes for authenticating with private repositories.
Using SSH:
git+ssh://git@<hostname>/...
(e.g.git+ssh://git@github.com/astral-sh/uv
)git+ssh://git@<host>/...
(e.g.git+ssh://git@github.com-key-2/astral-sh/uv
)
See the GitHub SSH documentation for more details on how to configure SSH.
Using a password or token:
git+https://<user>:<token>@<hostname>/...
(e.g.git+https://git:github_pat_asdf@github.com/astral-sh/uv
)git+https://<token>@<hostname>/...
(e.g.git+https://github_pat_asdf@github.com/astral-sh/uv
)git+https://<user>@<hostname>/...
(e.g.git+https://git@github.com/astral-sh/uv
)
When using a GitHub personal access token, the username is arbitrary. GitHub does not support logging in with password directly, although other hosts may. If a username is provided without credentials, you will be prompted to enter them.
If there are no credentials present in the URL and authentication is needed, the Git credential helper will be queried.
uv supports credentials over HTTP when querying package registries.
Authentication can come from the following sources, in order of precedence:
- The URL, e.g.,
https://<user>:<password>@<hostname>/...
- A
netrc
configuration file - A keyring provider (requires opt-in)
If authentication is found for a single net location (scheme, host, and port), it will be cached for the duration of the command and used for other queries to that net location. Authentication is not cached across invocations of uv.
Note --keyring-provider subprocess
or UV_KEYRING_PROVIDER=subprocess
must be provided to enable keyring-based
authentication.
Authentication may be used for hosts specified in the following contexts:
index-url
extra-index-url
find-links
package @ https://...
See the pip
compatibility guide for details on differences from
pip
.
uv uses aggressive caching to avoid re-downloading (and re-building dependencies) that have already been accessed in prior runs.
The specifics of uv's caching semantics vary based on the nature of the dependency:
- For registry dependencies (like those downloaded from PyPI), uv respects HTTP caching headers.
- For direct URL dependencies, uv respects HTTP caching headers, and also caches based on the URL itself.
- For Git dependencies, uv caches based on the fully-resolved Git commit hash. As such,
uv pip compile
will pin Git dependencies to a specific commit hash when writing the resolved dependency set. - For local dependencies, uv caches based on the last-modified time of the source archive (i.e.,
the local
.whl
or.tar.gz
file). For directories, uv caches based on the last-modified time of thepyproject.toml
,setup.py
, orsetup.cfg
file.
It's safe to run multiple uv
commands concurrently, even against the same virtual environment.
uv's cache is designed to be thread-safe and append-only, and thus robust to multiple concurrent
readers and writers. uv applies a file-based lock to the target virtual environment when installing,
to avoid concurrent modifications across processes.
Note that it's not safe to modify the uv cache directly (e.g., uv cache clean
) while other uv
commands are running, and never safe to modify the cache directly (e.g., by removing a file or
directory).
If you're running into caching issues, uv includes a few escape hatches:
- To force uv to revalidate cached data for all dependencies, run
uv pip install --refresh ...
. - To force uv to revalidate cached data for a specific dependency, run, e.g.,
uv pip install --refresh-package flask ...
. - To force uv to ignore existing installed versions, run
uv pip install --reinstall ...
. - To clear the global cache entirely, run
uv cache clean
.
By default, uv follows the standard Python dependency resolution strategy of preferring the
latest compatible version of each package. For example, uv pip install flask>=2.0.0
will
install the latest version of Flask (at time of writing: 3.0.0
).
However, uv's resolution strategy can be configured to support alternative workflows. With
--resolution=lowest
, uv will install the lowest compatible versions for all dependencies,
both direct and transitive. Alternatively, --resolution=lowest-direct
will opt for the
lowest compatible versions for all direct dependencies, while using the latest
compatible versions for all transitive dependencies. This distinction can be particularly useful
for library authors who wish to test against the lowest supported versions of direct dependencies
without restricting the versions of transitive dependencies.
For example, given the following requirements.in
file:
flask>=2.0.0
Running uv pip compile requirements.in
would produce the following requirements.txt
file:
# This file was autogenerated by uv via the following command:
# uv pip compile requirements.in
blinker==1.7.0
# via flask
click==8.1.7
# via flask
flask==3.0.0
itsdangerous==2.1.2
# via flask
jinja2==3.1.2
# via flask
markupsafe==2.1.3
# via
# jinja2
# werkzeug
werkzeug==3.0.1
# via flask
However, uv pip compile --resolution=lowest requirements.in
would instead produce:
# This file was autogenerated by uv via the following command:
# uv pip compile requirements.in --resolution=lowest
click==7.1.2
# via flask
flask==2.0.0
itsdangerous==2.0.0
# via flask
jinja2==3.0.0
# via flask
markupsafe==2.0.0
# via jinja2
werkzeug==2.0.0
# via flask
By default, uv will accept pre-release versions during dependency resolution in two cases:
- If the package is a direct dependency, and its version markers include a pre-release specifier
(e.g.,
flask>=2.0.0rc1
). - If all published versions of a package are pre-releases.
If dependency resolution fails due to a transitive pre-release, uv will prompt the user to
re-run with --prerelease=allow
, to allow pre-releases for all dependencies.
Alternatively, you can add the transitive dependency to your requirements.in
file with a
pre-release specifier (e.g., flask>=2.0.0rc1
) to opt in to pre-release support for that specific
dependency.
Pre-releases are notoriously difficult to model, and are a frequent source of bugs in other packaging tools. uv's pre-release handling is intentionally limited and intentionally requires user opt-in for pre-releases, to ensure correctness.
For more, see "Pre-release compatibility"
Historically, pip
has supported "constraints" (-c constraints.txt
), which allows users to
narrow the set of acceptable versions for a given package.
uv supports constraints, but also takes this concept further by allowing users to override the
acceptable versions of a package across the dependency tree via overrides (--override overrides.txt
).
In short, overrides allow the user to lie to the resolver by overriding the declared dependencies of a package. Overrides are a useful last resort for cases in which the user knows that a dependency is compatible with a newer version of a package than the package declares, but the package has not yet been updated to declare that compatibility.
For example, if a transitive dependency declares pydantic>=1.0,<2.0
, but the user knows that
the package is compatible with pydantic>=2.0
, the user can override the declared dependency
with pydantic>=2.0,<3
to allow the resolver to continue.
While constraints are purely additive, and thus cannot expand the set of acceptable versions for a package, overrides can expand the set of acceptable versions for a package, providing an escape hatch for erroneous upper version bounds.
By default, uv's pip-compile
command produces a resolution that's known to be compatible with
the current platform and Python version. Unlike Poetry and PDM, uv does not yet produce a
machine-agnostic lockfile (#2679).
However, uv does support resolving for alternate platforms and Python versions via the
--python-platform
and --python-version
command line arguments.
For example, if you're running uv on macOS, but want to resolve for Linux, you can run
uv pip compile --python-platform=linux requirements.in
to produce a manylinux2014
-compatible
resolution.
Similarly, if you're running uv on Python 3.9, but want to resolve for Python 3.8, you can run
uv pip compile --python-version=3.8 requirements.in
to produce a Python 3.8-compatible resolution.
The --python-platform
and --python-version
arguments can be combined to produce a resolution for
a specific platform and Python version, enabling users to generate multiple lockfiles for
different environments from a single machine.
N.B. Python's environment markers expose far more information about the current machine
than can be expressed by a simple --python-platform
argument. For example, the platform_version
marker
on macOS includes the time at which the kernel was built, which can (in theory) be encoded in
package requirements. uv's resolver makes a best-effort attempt to generate a resolution that is
compatible with any machine running on the target --python-platform
, which should be sufficient for
most use cases, but may lose fidelity for complex package and platform combinations.
uv supports an --exclude-newer
option to limit resolution to distributions published before a specific
date, allowing reproduction of installations regardless of new package releases. The date may be specified
as an RFC 3339 timestamp (e.g., 2006-12-02T02:07:43Z
) or
UTC date in the same format (e.g., 2006-12-02
).
Note the package index must support the upload-time
field as specified in PEP 700
.
If the field is not present for a given distribution, the distribution will be treated as unavailable.
To ensure reproducibility, messages for unsatisfiable resolutions will not mention that distributions were excluded
due to the --exclude-newer
flag — newer distributions will be treated as if they do not exist.
By default, uv loads certificates from the bundled webpki-roots
crate. The webpki-roots
are a
reliable set of trust roots from Mozilla, and including them in uv improves portability and
performance (especially on macOS, where reading the system trust store incurs a significant delay).
However, in some cases, you may want to use the platform's native certificate store, especially if
you're relying on a corporate trust root (e.g., for a mandatory proxy) that's included in your
system's certificate store. To instruct uv to use the system's trust store, run uv with the
--native-tls
command-line flag, or set the UV_NATIVE_TLS
environment variable to true
.
If a direct path to the certificate is required (e.g., in CI), set the SSL_CERT_FILE
environment
variable to the path of the certificate bundle, to instruct uv to use that file instead of the
system's trust store.
If client certificate authentication (mTLS) is desired, set the SSL_CLIENT_CERT
environment
variable to the path of the PEM formatted file containing the certificate followed by the private key.
uv has Tier 1 support for the following platforms:
- macOS (Apple Silicon)
- macOS (x86_64)
- Linux (x86_64)
- Windows (x86_64)
uv is continuously built, tested, and developed against its Tier 1 platforms. Inspired by the Rust project, Tier 1 can be thought of as "guaranteed to work".
uv has Tier 2 support ("guaranteed to build") for the following platforms:
- Linux (PPC64)
- Linux (PPC64LE)
- Linux (aarch64)
- Linux (armv7)
- Linux (i686)
- Linux (s390x)
uv ships pre-built wheels to PyPI for its Tier 1 and Tier 2 platforms. However, while Tier 2 platforms are continuously built, they are not continuously tested or developed against, and so stability may vary in practice.
Beyond the Tier 1 and Tier 2 platforms, uv is known to build on i686 Windows, and known not to build on aarch64 Windows, but does not consider either platform to be supported at this time. The minimum supported Windows version is Windows 10, following Rust's own Tier 1 support.
uv supports and is tested against Python 3.8, 3.9, 3.10, 3.11, and 3.12.
uv accepts the following command-line arguments as environment variables:
UV_INDEX_URL
: Equivalent to the--index-url
command-line argument. If set, uv will use this URL as the base index for searching for packages.UV_EXTRA_INDEX_URL
: Equivalent to the--extra-index-url
command-line argument. If set, uv will use this space-separated list of URLs as additional indexes when searching for packages.UV_CACHE_DIR
: Equivalent to the--cache-dir
command-line argument. If set, uv will use this directory for caching instead of the default cache directory.UV_NO_CACHE
: Equivalent to the--no-cache
command-line argument. If set, uv will not use the cache for any operations.UV_RESOLUTION
: Equivalent to the--resolution
command-line argument. For example, if set tolowest-direct
, uv will install the lowest compatible versions of all direct dependencies.UV_PRERELEASE
: Equivalent to the--prerelease
command-line argument. For example, if set toallow
, uv will allow pre-release versions for all dependencies.UV_SYSTEM_PYTHON
: Equivalent to the--system
command-line argument. If set totrue
, uv will use the first Python interpreter found in the systemPATH
. WARNING:UV_SYSTEM_PYTHON=true
is intended for use in continuous integration (CI) or containerized environments and should be used with caution, as modifying the system Python can lead to unexpected behavior.UV_PYTHON
: Equivalent to the--python
command-line argument. If set to a path, uv will use this Python interpreter for all operations.UV_BREAK_SYSTEM_PACKAGES
: Equivalent to the--break-system-packages
command-line argument. If set totrue
, uv will allow the installation of packages that conflict with system-installed packages. WARNING:UV_BREAK_SYSTEM_PACKAGES=true
is intended for use in continuous integration (CI) or containerized environments and should be used with caution, as modifying the system Python can lead to unexpected behavior.UV_NATIVE_TLS
: Equivalent to the--native-tls
command-line argument. If set totrue
, uv will use the system's trust store instead of the bundledwebpki-roots
crate.UV_INDEX_STRATEGY
: Equivalent to the--index-strategy
command-line argument. For example, if set tounsafe-any-match
, uv will consider versions of a given package available across all index URLs, rather than limiting its search to the first index URL that contains the package.UV_REQUIRE_HASHES
: Equivalent to the--require-hashes
command-line argument. If set totrue
, uv will require that all dependencies have a hash specified in the requirements file.UV_CONSTRAINT
: Equivalent to the--constraint
command-line argument. If set, uv will use this file as the constraints file. Uses space-separated list of files.UV_OVERRIDE
: Equivalent to the--override
command-line argument. If set, uv will use this file as the overrides file. Uses space-separated list of files.UV_LINK_MODE
: Equivalent to the--link-mode
command-line argument. If set, uv will use this as a link mode.UV_NO_BUILD_ISOLATION
: Equivalent to the--no-build-isolation
command-line argument. If set, uv will skip isolation when building source distributions.UV_CUSTOM_COMPILE_COMMAND
: Used to overrideuv
in the output header of therequirements.txt
files generated byuv pip compile
. Intended for use-cases in whichuv pip compile
is called from within a wrapper script, to include the name of the wrapper script in the output file.UV_KEYRING_PROVIDER
: Equivalent to the--keyring-provider
command-line argument. If set, uv will use this value as the keyring provider.UV_CONFIG_FILE
: Equivalent to the--config-file
command-line argument. Expects a path to a localuv.toml
file to use as the configuration file.UV_CONCURRENT_DOWNLOADS
: Sets the maximum number of in-flight concurrent downloads thatuv
will perform at any given time.UV_CONCURRENT_BUILDS
: Sets the maximum number of source distributions thatuv
will build concurrently at any given time.UV_CONCURRENT_INSTALLS
: Used to control the number of threads used when installing and unzipping packages.UV_EXCLUDE_NEWER
: Equivalent to the--exclude-newer
command-line argument. If set, uv will exclude distributions published after the specified date.
In each case, the corresponding command-line argument takes precedence over an environment variable.
In addition, uv respects the following environment variables:
SSL_CERT_FILE
: If set, uv will use this file as the certificate bundle instead of the system's trust store.SSL_CLIENT_CERT
: If set, uv will use this file for mTLS authentication. This should be a single file containing both the certificate and the private key in PEM format.RUST_LOG
: If set, uv will use this value as the log level for its--verbose
output. Accepts any filter compatible with thetracing_subscriber
crate. For example,RUST_LOG=trace
will enable trace-level logging. See the tracing documentation for more.HTTP_PROXY
,HTTPS_PROXY
,ALL_PROXY
: The proxy to use for all HTTP/HTTPS requests.HTTP_TIMEOUT
(orUV_HTTP_TIMEOUT
): If set, uv will use this value (in seconds) as the timeout for HTTP reads (default: 30 s).PYC_INVALIDATION_MODE
: The validation modes to use when run with--compile
. See:PycInvalidationMode
.VIRTUAL_ENV
: Used to detect an activated virtual environment.CONDA_PREFIX
: Used to detect an activated Conda environment.PROMPT
: Used to detect the use of the Windows Command Prompt (as opposed to PowerShell).NU_VERSION
: Used to detect the use of NuShell.FISH_VERSION
: Used to detect the use of the Fish shell.BASH_VERSION
: Used to detect the use of the Bash shell.ZSH_VERSION
: Used to detect the use of the Zsh shell.MACOSX_DEPLOYMENT_TARGET
: Used with--python-platform macos
and related variants to set the deployment target (i.e., the minimum supported macOS version). Defaults to12.0
, the least-recent non-EOL macOS version at time of writing.NO_COLOR
: Disable colors. Takes precedence overFORCE_COLOR
. See no-color.org.FORCE_COLOR
: Enforce colors regardless of TTY support. See force-color.org.
uv uses a custom versioning scheme in which the minor version number is bumped for breaking changes, and the patch version number is bumped for bug fixes, enhancements, and other non-breaking changes.
uv does not yet have a stable API; once uv's API is stable (v1.0.0), the versioning scheme will adhere to Semantic Versioning.
uv's dependency resolver uses PubGrub under the hood. We're grateful to the PubGrub maintainers, especially Jacob Finkelman, for their support.
uv's Git implementation is based on Cargo.
Some of uv's optimizations are inspired by the great work we've seen in pnpm, Orogene, and Bun. We've also learned a lot from Nathaniel J. Smith's Posy and adapted its trampoline for Windows support.
uv is licensed under either of
- Apache License, Version 2.0, (LICENSE-APACHE or https://www.apache.org/licenses/LICENSE-2.0)
- MIT license (LICENSE-MIT or https://opensource.org/licenses/MIT)
at your option.
Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in uv by you, as defined in the Apache-2.0 license, shall be dually licensed as above, without any additional terms or conditions.