That's not always an option on a router or appliance that comes with the software pre-installed.

Solution: If care about control, then do not buy routers or appliances that come with software pre-installed. Building a router kernel and userland from source is easy to do with BSD or something like OpenWRT.

Usually open source routers use a single "crunched" or "multicall" binary for utilties such as those in Linux coreutils, the subject of this thread. The process for making crunched binaries in NetBSD is really easy. Compiling busybox is probably not too difficult either.

The router (gateway) is the most important computer on the network IMHO. If one buys a router that one cannot control, then to me that suggests the buyer does not really care about controlling the computers that use it.

Maybe a computer owner must use a commercial OS that includes pre-installed software. It might be nigh impossible for the computer owner compile that OS from source themselves, let alone the pre-installed software (e.g., humongous web browser).

However a router is a much smaller system, no need for graphics or a web browser, and one can compile this from source relatively easily.