I couldn't see GNU Hello mentioned in the article or comments so far. I wonder how it fares bug-wise.
The GNU Hello program produces a familiar, friendly greeting. Yes, this is another implementation of the classic program that prints “Hello, world!” when you run it.
However, unlike the minimal version often seen, GNU Hello processes its argument list to modify its behavior, supports greetings in many languages, and so on. The primary purpose of GNU Hello is to demonstrate how to write other programs that do these things; it serves as a model for GNU coding standards and GNU maintainer practices.
/* Even exiting has subtleties. On exit, if any writes failed, change
the exit status. The /dev/full device on GNU/Linux can be used for
testing; for instance, hello >/dev/full should exit unsuccessfully.
This is implemented in the Gnulib module "closeout". */
The GNU Hello program produces a familiar, friendly greeting. Yes, this is another implementation of the classic program that prints “Hello, world!” when you run it.
However, unlike the minimal version often seen, GNU Hello processes its argument list to modify its behavior, supports greetings in many languages, and so on. The primary purpose of GNU Hello is to demonstrate how to write other programs that do these things; it serves as a model for GNU coding standards and GNU maintainer practices.
https://www.gnu.org/software/hello/