Setup a Development Python environment in Linux

January 10, 2026 · View on GitHub

This guide will work on Ubuntu > 20.x

1. Install Python3, Pip and dev tools

If you want to install a minimum packages and dependencies, then install python and pip only.

$ sudo apt -yqq install python3 python3-pip

But if you want full python installation, then run this:

$ sudo apt -yqq install python3 python3-pip build-essential libssl-dev libffi-dev python3-dev python3-venv

Let's check packages and modules in a minimum python installation.

$ python3 -V
Python 3.11.4

$ pip -V
pip 23.0.1 from /usr/lib/python3/dist-packages/pip (python 3.11)

$ pip list | wc -l
13

2. Working with Pip and virtual environments

2.1. virtualenv, venv and pipx?

$ pip install virtualenv

error: externally-managed-environment

× This environment is externally managed
╰─> To install Python packages system-wide, try apt install
    python3-xyz, where xyz is the package you are trying to
    install.
    
    If you wish to install a non-Debian-packaged Python package,
    create a virtual environment using python3 -m venv path/to/venv.
    Then use path/to/venv/bin/python and path/to/venv/bin/pip. Make
    sure you have python3-full installed.
    
    If you wish to install a non-Debian packaged Python application,
    it may be easiest to use pipx install xyz, which will manage a
    virtual environment for you. Make sure you have pipx installed.
    
    See /usr/share/doc/python3.11/README.venv for more information.

note: If you believe this is a mistake, please contact your Python installation or OS distribution provider. You can override this, at the risk of breaking your Python installation or OS, by passing --break-system-packages.
hint: See PEP 668 for the detailed specification.
  • The above error means that we can not install any python app and because that is mixing apt provided packages and pip provided packages.
  • If you wat to go for it, you have 2 options:
    1. Install virtualenv or venv and python will create something like .venv dirs in your repo.
    2. Install pipx and python will manage .venv in ~/.local/pipx/venvs for you automatically. Recommended if app will be used in many places.

2.2. Working with venv instead of virtualenv

1. Install venv

  • We will use python3 -m venv path/to/.venv instead of python3 -m virtualenv path/to/venv.
  • The venv should be instaled using this command apt install python3-venv or apt install python3.11-venv.
  • According the above error python3-full should be installed.
$ sudo apt -y install python3-venv python3-full

In a current empty directory create a virtual environment.

$ python3 -m venv .venv

2. Activate the virtual environment

Activate the virtualenv before updating or installing modules.

$ source .venv/bin/activate

And if you want to disable, just run deactivate.

3. Install packages in virtual env

Now, install any module you want in the project directory.

$ pip install flask

Check how many modules you have now.

$ pip list | wc -l
13

$ pip list 
Package            Version
------------------ -------
click              8.1.3
Flask              2.1.2
importlib-metadata 4.11.4
itsdangerous       2.1.2
Jinja2             3.1.2
MarkupSafe         2.1.1
pip                22.1.2
setuptools         62.3.4
Werkzeug           2.1.2
wheel              0.37.1
zipp               3.8.0

Get the module details that you installed.

$ pip show flask

4. Add the virtual environment folder to your existing git ignore file

$ echo ".venv" >> .gitignore

5. Freezing the modules for your specific python project

$  pip freeze > requirements.txt

Checking what modules were included in our requirements.txt.

$ cat requirements.txt 

click==8.1.3
Flask==2.1.2
importlib-metadata==4.11.4
itsdangerous==2.1.2
Jinja2==3.1.2
MarkupSafe==2.1.1
Werkzeug==2.1.2
zipp==3.8.0

6. Installing the modules from requirements file

$  pip -q install -r requirements.txt

7. List and update outdated modules

$  pip list --outdated

In this example, you will see:

Package    Version Latest Type
---------- ------- ------ -----
setuptools 62.3.4  62.6.0 wheel

Now, you can update those modules:

$ pip install -U setuptools

Or using the requirements.txt file:

$ pip install -U -r requirements.txt

Once updated, generate an updated requirements.txt file.

$ pip freeze > requirements.txt

8. Check for missing dependencies

$ python -m pip check

2.3. Working with pipx

1. Install pipx

  • The venv and ensurepip are required by pipx.
  • According the above error python3-full should be installed as well.
$ sudo apt install -y pipx python3-full
$ pipx ensurepath

/home/chilcano/.local/bin is already in PATH.

⚠️  All pipx binary directories have been added to PATH. If you are sure you want to proceed, try again with the '--force' flag.

Otherwise pipx is ready to go! ✨ 🌟 ✨

2. Install a python applications using pipx

$ pipx install deployguard

  installed package deployguard 0.1.2, installed using Python 3.12.3
  These apps are now globally available
    - deployguard
done! ✨ 🌟 ✨

$ deployguard --help

Usage: deployguard [OPTIONS] COMMAND [ARGS]...

  DeployGuard - Audit Foundry deployment scripts for security vulnerabilities.

Options:
  --version  Show the version and exit.
  --help     Show this message and exit.

Commands:
  audit   Analyze deployment scripts for security vulnerabilities.
  check   Check test coverage for deployment scripts.
  rules   List all available rules.
  verify  Verify deployed proxy against expected implementation.

3. Configuring VS Code to work with Python

Recommended extensions:

  1. xxx
  2. yyy
  3. zzzz