library(xref) of previous releases has been replaced by a much more powerful tool, spxref, originally written by Tom Howland.

The main purpose of the cross-referencer is to find unreachable code. To this end, it begins by looking for a definition for user:runtime_entry/1 and also looks for initializations, hooks, module export lists and public directives to start tracing the reachable code from.

A second function is to aid in the formation of module statements. It can list all of the required module/2 and use_module/2 statements by file.

See The Cross-Referencer.