pixis internal uv does not recognize UV_NATIVE_TLS env variable #4896
Description
Checks
-
I have checked that this issue has not already been reported.
-
I have confirmed this bug exists on the latest version of pixi, using
pixi --version.
Reproducible example
Commands I ran and their output:
UV_NATIVE_TLS=true pixi run uv pip install blackworks fine but
UV_NATIVE_TLS=true pixi add --pypi blackerrors with
Error: × failed to solve the pypi requirements of environment 'default' for platform 'linux-64'
├─▶ failed to resolve pypi dependencies
├─▶ Failed to fetch: `[https://pypi.org/simple/black/`](https://pypi.org/simple/black/%60)
├─▶ Request failed after 3 retries
├─▶ error sending request for url .../repository/pypi/simple/black/)
├─▶ client error (Connect)
╰─▶ invalid peer certificate: UnknownIssuer
It looks like that pixi's uv does not recognize UV_NATIVE_TLS to use native tls instead of rustls.
pixi.toml/pyproject.toml file that reproduces my issue:
[workspace]
channels = [".../repository/conda-forge"]
platforms = ["linux-64"]
conda-pypi-map = {".../repository/conda-forge" = "compressed_mapping.json"} # from https://github.com/prefix-dev/parselmouth/blob/main/files/compressed_mapping.json
[dependencies]
python = ">=3.11"
uv = "*"
pixi info output:
System
------------
Pixi version: 0.55.0
Platform: linux-64
Virtual packages: __unix=0=0
: __linux=4.18.0=0
: __glibc=2.39=0
: __archspec=1=skylake_avx512
Cache dir: .../.cache/rattler/cache
Auth storage: .../.rattler/credentials.json
Config locations: .../uv-pixi-test/.pixi/config.toml /etc/pixi/config.toml
Global
------------
Bin dir: .../.pixi/bin
Environment dir: .../.pixi/envs
Manifest dir: .../.pixi/manifests/pixi-global.toml
Workspace
------------
Name: uv-pixi-test
Version: 0.1.0
Manifest file: .../uv-pixi-test/pixi.toml
Last updated: 06-11-2025 14:37:44
Environments
------------
Environment: default
Features: default
Channels: .../repository/conda-forge
Dependency count: 2
Dependencies: python, uv
Target platforms: linux-64
Prefix location: .../uv-pixi-test/.pixi/envs/default
Other files (e.g. script files, source files, etc.):
Issue description
I am in corporate network. I can't test on latest pixi version but will update as soon as a new version is rolled out for us.
Expected behavior
UV_NATIVE_TLS=true pixi add --pypi blackThis should work and recognize the env variable.