Not externally, but there's plenty of documentation and version control history internally, and many witnesses who can attest to the accuracy of those records.

Not externally, but there's plenty of documentation and version control history internally, and many witnesses who can attest to the accuracy of those records. That may or may not be sufficient evidence of prior art. For the Perl implementation, the basis of the design came from the book "Network Programming with Perl" by Lincoln Stein. I'm pretty sure he covered the basic "accept a connection and fork" pattern, and in the Perl world the big benefit of the pattern is the pre-loading and compiling of modules/classes that the forked process is going to need. So that book probably contains sufficient published prior-art.