"serious" might not be the right term[1][2], but Dusk OS[3] has a wide set of features, including a C compiler[4] and a Text editor[5] which clocks at 339 lines

"serious" might not be the right term[1][2], but Dusk OS[3] has a wide set of features, including a C compiler[4] and a Text editor[5] which clocks at 339 lines of code[6][7] (third of a kilo?). You can see the editor in action at time 2:30 of the first screencast[8] on the Dusk OS website [1]: https://lists.sr.ht/~vdupras/duskos-discuss/%3CZ0Cr6m01ZNaANMLx@arendt%3E https://lists.sr.ht/~vdupras/duskos-discuss/%3CZ0Cr6m01ZNaAN... [2]: https://lists.sr.ht/~vdupras/duskos-discuss/%3CCADfQ9L9D6DNRODj+PQ2jQLbTgbN9XUmyG9p--wfGE72AUsNQyg@mail.gmail.com%3E https://lists.sr.ht/~vdupras/duskos-discuss/%3CCADfQ9L9D6DNR... [3]: http://duskos.org http://duskos.org [4]: https://git.sr.ht/~vdupras/duskos/tree/master/item/fs/doc/comp/c.txt https://git.sr.ht/~vdupras/duskos/tree/master/item/fs/doc/co... [5]: https://git.sr.ht/~vdupras/duskos/tree/master/item/fs/doc/text/ged.txt https://git.sr.ht/~vdupras/duskos/tree/master/item/fs/doc/te... [6]: https://git.sr.ht/~vdupras/duskos/tree/master/item/fs/text/ed.fs https://git.sr.ht/~vdupras/duskos/tree/master/item/fs/text/e... [7]: https://git.sr.ht/~vdupras/duskos/tree/master/item/fs/text/ged.fs https://git.sr.ht/~vdupras/duskos/tree/master/item/fs/text/g... [8]: https://duskos.org/demo.html https://duskos.org/demo.html