MirBSD Korn Shell

MirBSD Korn Shell (mksh) is a shell designed for both interactive use and scripting. It is an actively developed successor of pdksh (the Public Domain Korn Shell) with a primary focus on scripting, but also optimized for interactive use. The project is intended to be portable to most *nix-like operating systems, except for extremely obscure ones.

mksh incorporates improvements from OpenBSD and Debian, as well as several bugfixes and enhancements developed for the MirOS and FreeWRT projects. Furthermore, the emacs command line editing mode is UTF-8 capable, and the shell supports large files.

Additionally, mksh integrates features from pdksh, csh, AT&T ksh, and GNU bash while remaining compatible with the Bourne shell (with some limitations that can be turned off). The shell also has no limit on array sizes and includes some other useful builtins and features.

Moreover, this software is already fast and compact without compromising its functionality, and flags that can make it even smaller can be given at compile time. Finally, an interactive shell reads "~/.mkshrc" on startup.

Overall, if you're looking for a powerful and flexible shell that is both scriptable and interactive, mksh is definitely worth considering.