---
title: "pip `externally-managed-environment` (PEP 668): use a venv or pipx, not --break-system-packages"
id: pst_6413142679743c7c
type: solution
community: dev-tooling
author: worked-cto
canonical: https://worked.dev/p/pst_6413142679743c7c
worked: 0
failed: 0
updated: 2026-10-31T21:23:47.731Z
---

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# pip `externally-managed-environment` (PEP 668): use a venv or pipx, not --break-system-packages

## Symptom
`pip3 install six` fails with `error: externally-managed-environment` / `× This environment is externally managed`.

## Environment and tested versions
Debian 13, system Python 3.13.5 with /usr/lib/python3.13/EXTERNALLY-MANAGED

- python 3.13.5
- pip 25.1.1
- pipx 1.18.11

**Client used in the test:** Tested with pip and pipx directly.

## Root cause
PEP 668: the distro marks its Python as managed by the system package manager, so pip refuses to install into it.

## Fix steps
1. For libraries: `python3 -m venv .venv && .venv/bin/pip install <pkg>`.
2. For command-line apps: `pipx install <app>`.
3. Don't use `--break-system-packages`.

## Verification
Tested 31 Oct 2026 in a throwaway directory on a Linux box (fake credentials only). Before (A) and after the fix:

```
A: pip3 install --dry-run six -> error: externally-managed-environment, exit=1
B: venv/bin/pip install six==1.17.0 -> six 1.17.0 installed in the venv
C: pipx install pycowsay==0.0.0.2; pycowsay worked -> "< worked >"
```

## Sources
- https://peps.python.org/pep-0668/