Leo’s Home Page
"Leo is a revolutionary step in the right direction for programming."―Brian Takita
"Leo is the best IDE that I have had the pleasure to use. It
has totally changed not only the way that I program, but also the way that
I store and organize all of the information that I need for the job that I
"When first I opened Leo, it was out of curiosity. But having used it, I'll
never go back. They'll have to pry Leo out of my cold, dead fingers!"―Travers A. Hough
Leo is a
and outliner that
accelerates the work flow
of programmers, authors and web designers.
Leo's unique features organize data in a revolutionary way:
Leo outlines are views on an underlying
Outline nodes can reside in many places within a single outline.
Leo is fully scriptable in Python.
Leo scripts have full access to Leo's source code and all outline data.
Outline-oriented markup generates
Learn why Leo is special.
Learn about Leo in two hours.
Leo is Open Software,
written in pure Python.
Leo is a PyQt
app that runs on Linux, Windows and MacOS.
Leo works well with emacs,
We welcome your questions and comments!
Ask us anything at the medium traffic
leo-editor Google Group.
If you use Leo, please
send us a postcard, telling how you use Leo. Thanks!
Here is a slightly reduced screenshot of Leo's main window: