I have created a set of class files that helps to create the route configuration array. I, however, do not know where to put the source files. I browsed around a little and found some answers that suggested I put up the code in packagist and install it via composer, but my classes are relatively small. So, I wanted to ask if there is another way to do it. The files must be accessible in all the modules.
Your application code is organised into modules and lives in module/<Modulename>/src/. If the code is something you might want to reuse in other applications, then it might make more sense to have it as a standalone library that you install via. Composer.