Creating environment using uv tries to use pip

[zoof]

System details:

Windows 11

Positron and OS details:

Positron Version: 2026.07.1 (user setup) build 5
Code - OSS Version: 1.118.0
Commit: d3cdd60
Date: 2026-07-08T19:52:09-06:00
Electron: 39.8.8
Chromium: 142.0.7444.265
Node.js: 22.22.1
V8: 14.2.231.22-electron.0
OS: Windows_NT x64 10.0.26200

Session details:

CTRL-Shift-P -> Python: Create Environment... -> uv Use uv to find a Python version locally (or install it if needed) for the new environment -> Python 3.12

Describe the issue:

Attempts to install "seed packages" using pip instead of uv.

Steps to reproduce the issue:

1. Attempt to have Positron use uv to create a new environment

Expected or desired behavior:

Environment should be created.

Were there any error messages in the UI, Output panel, or Developer Tools console?

Creating virtual environment with seed packages at: .venv
2026-07-14 16:39:15.529 [info] Found uv environment: c:\Users\<username>\test\.venv\Scripts\python.exe
2026-07-14 16:39:15.647 [info] Found uv environment: c:\Users\<username>\test\.venv\Scripts\python.exe
2026-07-14 16:39:23.441 [info] error: Failed to install seed packages into virtual environment
  Caused by: No solution found when resolving: `pip`
2026-07-14 16:39:23.442 [info] 
  Caused by: Request failed after 3 retries in 8.1s
  Caused by: Failed to fetch: `https://pypi.org/simple/pip/`
  Caused by: error sending request for url (https://pypi.org/simple/pip/)
  Caused by: client error (Connect)
  Caused by: invalid peer certificate: UnknownIssuer

hint: Consider enabling use of system TLS certificates with the `--system-certs` command-line flag
2026-07-14 16:39:23.452 [error] Error while running uv environment creation script
2026-07-14 16:39:23.452 [error] Failed to create virtual environment with exitCode: 2

[austin3dickey]

Hey @zoof, thanks for the issue and the detailed logs.

We're not trying to use pip here; the code that's running is something like uv venv .venv --no-project --seed -p 3.12. The --seed flag in particular is telling uv to install pip into the environment during the transaction, which is failing.

Looks like the TLS handshake is failing because uv doesn't trust the certificate it's being presented. UnknownIssuer almost always means there's a TLS-inspecting proxy, firewall, or antivirus on the network that re-signs HTTPS traffic with a custom root CA. That CA is usually installed in the Windows certificate store (so your browser trusts it), but uv ships its own bundled Mozilla root certificates by default and doesn't consult the OS store, so it rejects the connection.

Workarounds, most convenient first:

1. Tell uv to use the system certificate store. Since the environment is created from the Command Palette you can't pass a flag, but uv reads a config file automatically, so create %APPDATA%\uv\uv.toml (or a uv.toml in your project folder) with:

   system-certs = true

   No restart needed. This is the config-file form of uv's --system-certs flag.

2. If the system store still fails, export your corporate root CA as a PEM file, set the SSL_CERT_FILE environment variable to its path, and restart Positron.

Either of these should let the seed install reach pypi. If neither works, let us know a bit more about your network setup (corporate proxy, VPN, antivirus) and we can dig further.