pex

This release adds support for --pip-version 26.0.1.

• Add support for --pip-version 26.0.1. (#3098)

This release adds support for --pip-version 26.0.

• Add support for --pip-version 26.0. (#3091)

This release fixes a bug in constraints file requirement parsing. Previously, Pex tried to validate constraints beyond its own needs, anticipating Pip's needs, leading to a failure to handle direct reference URL requirements, including VCS requirements.

• Fix constraints file parsing for URL requirements. (#3090)

This release adds support for Linux PEX scies installing themselves with a desktop entry on first run. This is enabled via either of --scie-icon or --scie-desktop-file. By default, the end-user is prompted to approve a desktop install but this can be bypassed at build time with --no-scie-prompt-desktop-install or at runtime using the PEX_DESKTOP_INSTALL environment variable.

• Add PEX scie Linux .desktop install support. (#3087)

This release upgrades vendored `packaginged for Python>=3.8 to the latest release; bringing some bug fixes and performance improvements.

• Upgrade vendored packaging to 26.0 for Python>=3.8. (#3083)

This release makes running a PEX using venv-execution and sh-bootstrapping (that is, build with --sh-boot --venv) more likely to behave identically with a cold or warm PEX_ROOT cache. This includes running with PEX_PYTHON=..., PEX_PYTHON_PATH=..., PEX_PATH=..., PEX_VENV=... and PEX_IGNORE_RCFILES=....

• Avoid fast-path in --sh-boot script for more variables. (#2729)

This release upgrades the floor of science to 0.17.2 to pick up better handling for CPython 3.9 which was dropped in new [PBS][PBS] releases at the end of 2025.

• Upgrade science to 0.17.2 (#3081)

This release introduces a new --interpreter-selection-strategy option for use when building PEXes that use --interpreter-constraints. When multiple interpreters satisfy the specified --interpreter-constraints, the --interpreter-selection-strategy allows you to direct Pex to select the oldest (the default and the existing behavior) or the newest. In either case, the highest available patch version will be selected from amongst multiple interpeters with the same major and minor versions.

• Support an --interpreter-selection-strategy option. (#3080)

This release causes pex ... to emit the output path of the generated PEX (and / or scies) on STDOUT. If --seed verbose is set, then the output path of the PEX is included in the new "seeded_from" field.

• Emit PEX output path to stdout. (#3079)

This release adds support for templating {platform} in PEX file names. When this substitution token is found, it is replaced with the most specific platform tag(s) of wheels in the PEX. For example:

:; python -mpex ansicolors -o "ansicolors-{platform}.pex"

:; ./ansicolors-py2.py3-none-any.pex
Pex 2.83.0 hermetic environment with 1 requirement and 1 activated distribution.
Python 3.14.2 (main, Dec  5 2025, 14:39:48) [GCC 15.2.0] on linux
Type "help", "pex", "copyright", "credits" or "license" for more information.
>>> pex()
Running from PEX file: ./ansicolors-py2.py3-none-any.pex
Requirements:
  ansicolors
Activated Distributions:
  ansicolors-1.1.8-py2.py3-none-any.whl
>>>

:; python -mpex \
    --complete-platform package/complete-platforms/linux-x86_64.json \
    --complete-platform package/complete-platforms/macos-aarch64.json ansible \
    -o "ansible-{platform}.pex"

:; ./ansible-cp314-cp314-macosx_11_0_arm64.manylinux2014_x86_64.pex
Pex 2.83.0 hermetic environment with 1 requirement and 10 activated distributions.
Python 3.14.2 (main, Dec  5 2025, 14:39:48) [GCC 15.2.0] on linux
Type "help", "pex", "copyright", "credits" or "license" for more information.
>>> pex()
Running from PEX file: ./ansible-cp314-cp314-macosx_11_0_arm64.manylinux2014_x86_64.pex
Requirements:
  ansible
Activated Distributions:
  ansible-13.2.0-py3-none-any.whl
  ansible_core-2.20.1-py3-none-any.whl
  jinja2-3.1.6-py3-none-any.whl
  markupsafe-3.0.3-cp314-cp314-manylinux2014_x86_64.manylinux_2_17_x86_64.manylinux_2_28_x86_64.whl
  pyyaml-6.0.3-cp314-cp314-manylinux2014_x86_64.manylinux_2_17_x86_64.manylinux_2_28_x86_64.whl
  cryptography-46.0.3-cp311-abi3-manylinux_2_34_x86_64.whl
  cffi-2.0.0-cp314-cp314-manylinux2014_x86_64.manylinux_2_17_x86_64.whl
  pycparser-2.23-py3-none-any.whl
  packaging-25.0-py3-none-any.whl
  resolvelib-1.2.1-py3-none-any.whl
>>>

• Support a {platform} placeholder in PEX file names. (#3078)

This release fixes pex3 scie create --dest-dir to work when the specified PEX is a local file path. Previously --dest-dir only worked when the specified PEX was an URL.

• Fix pex3 scie create --dest-dir handling. (#3076)

This release adds support for resource path bindings to plain PEXes as a follow-on to adding resource binding support for PEX scies in the 2.81.0 release. Resource paths are bound to environment variables with --bind-resource-path. Additionally, the existing --inject-args option now supports replacement of {pex.env.<env var name>} placeholders with the corresponding environment variable value. Notably, the combination of these features allows passing the paths of files contained in a PEX to third party scripts without extra shim code.

• Support passing PEX file paths to 3rd party scripts. (#3074)

This release adds the ability to set a custom scie entrypoint for PEX scies using --scie-exe, --scie-args and --scie-env, as well as bind resource paths to environment variables using --scie-bind-resource-path. The combination of these new features allows broad flexibility defining a PEX scie's boot command.

Additionally, the pex3 scie create command gains the ability to use a URL for the PEX to convert to a scie and optionally specify a size (via #size=<expected size>) and / or fingerprint (via #<algorithm>=<expected fingerprint>) to verify the download against.

• Support converting existing Pants PEXes to performant scies. (#3072)

This release adds the pex3 scie create tool for creating scies from existing PEX files. This works for PEXes created by Pex 2.1.25 (released on January 21st, 2021) and newer.

• Add a pex3 scie create command. (#3070)

This release adds the CPython[free-threaded] alias for CPython+t and the CPython[gil] alias for CPython-t when writing interpreter constraints.

• Add CPython[{free-threaded,gil}] aliases for CPython{+,-}t. (#3068)

This release adds support for the CPython+t implementation name in interpreter constraints to allow constraining selected interpreters to CPython interpreters built with free-threading support. The existing CPython implementation selects from either classic GIL enabled CPython interpreters or CPython free-threaded interpreters as was the case previously. The CPython-t implementation name can be used to require classic GIL-only CPython interpreters.

• Support CPython+t in ICs to select free-threaded CPython. (#3067)

This release updates vendored Pip's vendored certifi's cacert.pem to that from certifi 2026.1.4.

• Update vendored Pip's CA cert bundle. (#3065)

This release fixes venv creation from PEXes to avoid declaring false collisions in __init__.py files when the venv uses Python 3.9 or greater.

• Compare ASTs of colliding venv __init__.py. (#3063)

This release fixes a very old bug where the Pex PEX (or any other PEX created with --no-strip-pex-env) would, in fact, strip PEX_PYTHON and PEX_PYTHON_PATH.

• Fix PEX_PYTHON{,_PATH} stripping on Pex re-exec. (#3062)

This release has no fixes or new features per-se, but just changes the set of distributions that Pex releases to PyPI. Previously Pex released an sdist and a universal (py2.py3-none-any) .whl. Pex now releases two wheels in addition to the sdist. The py3.py312-none-any.whl targets Python>=3.12 and has un-needed vendored libraries elided making it bith a smaller .whl and less prone to false-positive security scan issues since unused vendored code is now omitted. The other wheel carries the same contents as prior and supports creating PEXes for Python 2.7 and Python>=3.5,<3.12.

• Split Pex .whl into two .whls. (#3057)

This release fixes bootstrapping of Pips specified via --pip-version to respect Pex Pip configuration options (like custom indexes) under Python 3.12 and newer.

• Fix Pip bootstrap to respect Pip config for Python >= 3.12. (#3054)

This release adds support for --no-scie-pex-entrypoint-env-passthrough to trigger direct execution of --venv PEX scie script entrypoints. This performance optimization mirrors the existing default --no-scie-busybox-pex-entrypoint-env-passthrough for busybox scies, but must be selected by passing --no-scie-pex-entrypoint-env-passthrough explicitly. In addition, the VIRTUAL_ENV env var is now guaranteed to be set for all --venv PEX scies.

• Add scie support for direct exec of venv scripts. (#3053)

This release updates vendored Pip's vendored certifi's cacert.pem to that from certifi 2025.11.12.

• Update vendored Pip's CA cert bundle. (#3052)

This release fixes Pex handling of wheels with bad RECORDs that record files that do not exist in the .whl file.

• Warn when non-existent files in RECORD, but proceed. (#3051)

This release adds supoort for --scie-load-dotenv to enable .env file loading in PEX scies.

• Support scie-jump .env loading with --scie-load-dotenv. (#3046)

This release fixes a bug gracefully handling a request for --validate-entry-point when no --entry-point was given.

• Error for missing entry point under --validate-entry-point. (#3048)

This release fixes building PEXes from direct URL requirements. Previously, the direct URL requirement would be recorded incorrectly in PEX-INFO metadata leading to a failure to boot.

• Fix str(req) of direct URLs with known versions. (#3043)

This release upgrades the floor of science to 0.17.1 and scie-jump to 1.9.2 to fix a regression in the breadth of Linux platforms --scie {eager,lazy} PEX scies were compatible with.

• Upgrade science to 0.17.1 & scie-jump to 1.9.2. (#3038)

This release adds support for setting custom PEX-INFO build_properties metadata via --build-property, --build-properties and --record-git-state.

• Support custom PEX-INFO build_properties. (#3036)

This release fixes --lock and --pylock subsetting of direct reference and VCS requirements. Previously, just the project name was matched when subsetting but now the normalized URL is matched. The previous behavior could lead to subsets succeeding that should have otherwise failed. The new behavior can lead to a subset failing when URLs differ, but both URLs point to the same content. Although this too is a bug, it should be a much narrower use case in the wild; so this should be an improvement.

• Fix URL requirement --lock & --pylock subsetting. (#3034)

This release upgrades the floor of science to 0.17.0 and scie-jump to 1.9.1 to pick up support for producing PEX scies for Linux aarch64 & x86_64 that link against glibc. Previously the embedded interpreter would link against glibc but the scie-jump at the PEX scie tip was a musl libc static binary and this could cause problems in those areas where glibc and musl diverge.

• Upgrade science to 0.17.0 & scie-jump to 1.9.1. (#3033)

This release fixes a regression introduced in the Pex 2.60.0 release when installing wheels with *.data/ entries whose top-level name matches a top-level package in the wheel. This regression only affected default --venv mode PEXes which populate site-packages using symlinks.

• Fix --venv (using symlinks) for some wheels. (#3031)

This release fixes Pex lock resolves (--lock and --pylock) to allow exceptions for --no-wheel and --no-build as a follow-on to the 2.71.1 release fix that enabled the same for Pip resolves.

• Allow exceptions for --no-{wheel,build} with locks. (#3028)

This release adds support for building foreign platform musl Linux PEX scies and dogfoods this to add musl Linux aarch64 & x86_64 Pex PEX scies to the Pex release.

• Support targeting foreign platform musl scies. (#3025)

This release fixes Pex to allow blanket disallowing builds but making targeted exceptions and vice-versa. The underlying Pip machinery has always supported this, but Pex just got in the way for no reason.

• Allow exceptions for --no-wheel & --no-build. (#3023)

This release upgrades the floor of science to 0.16.0 to pick up support for generating PEX scies for musl Linux aarch64.

• Upgrade science to 0.16.0. (#3020)

This release adds a feature for Pex developers. If you want to experiment with a new version of Pip you can now specify _PEX_PIP_VERSION=adhoc _PEX_PIP_ADHOC_REQUIREMENT=.... N.B.: This feature is for Pex development only.

• Support adhoc Pip versions in development. (#3011)

This release fixes handling of scoped repos. Previously, validation against duplicate scopes was too aggressive and disallowed multiple un-named indexes and find-links repositories.

• Allow multiple un-named indexes and find-links repos. (#3009)

This release fixes --venv-repository handling of top-level requirements that specify pre-releases. Such resolves now imply --pre.

• Root reqs that specify prereleases imply --pre. (#3004)

This release adds a pexec console script as an alias for pex3 run.

• Add pexec script as a pex3 run alias. (#3001)

This release fixes Pex to handle installing a wider variety of whls violating various PyPA specs.

• Handle two cases of bad whl metadata. (#2999)

This release bumps the floor of science to 0.15.1 to ensure least surprise with no bad --scie-hash-alg choices presented by the underlying science tool used to build Pex --scies.

• Upgrade science to 0.15.1. (#2995)

This release fixes a regression extracting sdists on some Pythons older than 3.12.

• Fix sdist tar extraction filtering for old Pythons. (#2992)

This release adds support for --project pointing to local project sdist or wheel paths in addition to the already supported local project directory path. The wheel case can be particularly useful when building a project wheel out of band is very much faster than letting Pex obtain the project metadata via a PEP-517 prepare_metadata_for_build_wheel call or via a wheel build via Pip, which is what Pex falls back to.

• Support --project pointing at sdists and whls. (#2989)

This release brings Pex into compliance with sdist archive features as specified in https://packaging.python.org/en/latest/specifications/source-distribution-format/#source-distribution-archive-features.

• Implement tar extraction data filtering. (#2987)

This release fixes a bug resolving editable projects from --venv-repositorys.

• Fix resolve of editables from --venv-repositorys. (#2984)

This release fixes a bug subsetting --venv-repository resolves when top-level requirements had version specifiers; e.g.: thing>2.

• Fix --venv-repository subsetting. (#2981)

This release adds support for specifying multiple --venv-repositorys when building a PEX. This allows creating multi-platform PEXes from multiple venvs that all satisfy a resolve, but for different interpreters.

• Multi-platform PEXes via multiple --venv-repositorys. (#2977)

This release improves upon the local project directory hashing fix in 2.61.1 by avoiding the hashing altogether unless creating a lock, where the resulting fingerprint is needed.

• Avoid fingerprinting local projects. (#2975)

This release adds support for --pip-version 25.3.

• Add support for --pip-version 25.3. (#2968)

This release adds support for PEX scies using CPython free-threaded builds. Most such scies should be able to auto-detect when a free-threaded CPython is needed, but new --scie-pbs-free-threaded and --scie-pbs-debug options have been added to explicitly request the desired PBS CPython build as well.

• Support free-threaded PEX scies. (#2967)

This release is a follow-up to 2.64.0 to fix a regression in locks for credentialed VCS requirements.

• Fix redaction of VCS URL credentials in locks. (#2964)

This release adds support for --avoid-downloads / --no-avoid-downloads to pex3 lock create. By default, when available, Pex now locks in --avoid-downloads mode using pip install --dry-run --ignore-installed --report to power lock generation instead of pip download. This saves time generating the lock at the expense of having to spend time downloading distributions later when using the lock to create a PEX or venv. This new lock mode produces byte-wise identical locks and is available for all Pip versions Pex supports save for vendored Pip (--pip-version {vendored,20.3.4-patched}).

• Use Pip --report to avoid pex3 lock create downloads. (#2962)

This release adds population of a pex script to venvs created with pex3 venv create. This allows for executing Python in the activated venv via /path/to/venv/pex ... instead of source /path/to/venv/bin/activate && python ....

• Include pex script in pex3 venv create. (#2960)

This release improves performance when creating venvs by eliminating an un-necessary re-hash of wheel files already installed in the Pex cache.

• Avoid re-hashing wheels when re-installing. (#2958)

This release brings full support for universal lock splitting. You can now declare conflicting top-level requirements for different (marker) environments and these will be isolated in separate lock resolves in the same universal lock file. These split resolves are performed in parallel and the appropriate split lock is later selected automatically when building a PEX or a venv from the lock.

As part of this work, locks also filter wheels more faithfully. If you supply interpreter constraints that constrain to CPython, the resulting lock will now only contain cp platform-specific wheels (and, for example, not PyPy wheels).

• Complete support for universal lock splitting. (#2940)

This release fixes a long-standing bug hashing local project directories when building PEXes. Pex now hashes the content of an exploded sdist for the local project just like it does when hashing local projects for a lock.

• Fix local project directory hashing. (#2954)

This release adds support for the Python 3.15 series early. Pex runs on 3.15.0a1, can produce scies for 3.15.0a1, etc.

• Officially begin supporting Python 3.15. (#2952)