livepython: Visually trace Python code in real-time


Livepython is a desktop app that lets you visually trace, in real-time, the execution of a Python program. In addition, it can track changes in global and local variables as your program is running. It is meant to give you a quick grasp of a program’s execution flow. It’s less messy than sprinkling print statements throughout your code and simpler to use than debuggers/profilers.

It can be launched from the command-line as easily as:

livepython [program] [args...]


SPACE: Play/Pause the program.

Left/Right Arrow: Change speed of execution.

V: Open/Close Variable Inspector.


Python 2.7, 3.5, & 3.6.


npm install livepython -g


It has 3 main components:

  • a Python tracer that uses sys.settrace() to intercept every line of your program as it’s being evaluated
  • an Electron app that is responsible for the rendering the Livepython frontend
  • a node.js gateway script that manages communication between the frontend and the tracer

If you want to make changes to Livepython, you will need to run webpack:


Then you can test your built version of livepython by running:

bin/livepython [your python program]

Copyright (c) 2017 Anastasis Germanidis