BusyBox combines tiny versions of many common UNIX utilities into a single small executable. It provides replacements for most of the utilities you usually find in GNU fileutils, shellutils, etc. The utilities in BusyBox generally have fewer options than their full-featured GNU cousins; however, the options that are included provide the expected functionality and behave very much like their GNU counterparts. BusyBox provides a fairly complete environment for any small or embedded system.
The Swiss Army Knife of Embedded Linux - BusyBox is a very good ingredient to craft space-efficient distributions.
$ docker run -it --rm clover/busybox
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