9Sense is best framed as a nightly mirror of 9front.
Mainly used as a jump point for making changes for cpu & file servers, and terminals within a grid environment, it also serves as an excellent example of OS architecture and design.
It is the Unix Philosophy on steriods, the ideas and concepts of this OS were beyond and ahead of its time.
But with no modern browser, no support for JS or CSS, 9front and Plan9 have quietly drifted far behind Windows, Linux, and the BSD's. Hell, HaikuOS is more well known. *sigh*