Vixn is a Linux/Unix programmers' text editor. The rationale behind it is that I've been using vim for several years so using a text editor without a vi-like command mode has become almost unthinkable, but I was frustrated with the limitations imposed by vim's one window  per instance model:
- When working with multiple files in different windows each has its own context so you can't take advantage of sharing the command history etc and are limited to the system's cut & paste facilities when moving text between files
- Working through compiler error messages is clumsy
- If you try to open a file that's already open in an obscured window you get an annoying error message
I chose to write vixn in python so that it automatically has a great language for customising and extending it, and development would be a bit quicker than if I used C. Writing a vi-like shell around gtksourceview also saved me a huge amount of time compared to writing a text editor engine, complete with syntax highlighting, from scratch, but it does come with a certain amount of baggage and quirks, especially when trying to make it behave like vi rather than a more straightforward type of editor.
Vixn in its current incarnation can't really replace vim altogether, but for editing several source files together as part of a project I already find vixn more convenient even at such an early stage of development.
Vixn borrows the concept of throwback windows from RISC OS programmers' editors to list compiler warnings and errors. Clicking one of the messages opens the source file (if necessary) in which the error occurred and places the cursor there. Throwback windows can also be used to list matches for a search - by default bound to the backslash (\) key (cf forward search /).
I've been using vixn as my main editor, especially for programming, for some years now, but never really got around to adding "polish" etc to make it appealing for other users. I've decided that if I get the time to make any major changes in future I will replace vixn with a gedit plugin. gedit has a lot of other useful features, but no up-to-date vi plugin.