Playing with route bindings and hashids to get a backwards compatible solution. It will not decode if it can't.

hashids-route-binding.php

<?php
// create a route like this

$this->route->get('projects/{id}', 'ProjectsController@show');


// Put this in your provider
// It will check if it can decode, else it will just return what was put in the url
$this->route->bind('id', function ($id) {
    return (new Hashids())->decode($id)[0] ?? $id;
});


// Example:

// 1). Not encoded: http://site.com/projects/3   

public function show($id)
{
   return $id;   // will return 3
}

// 2). Encoded: http://site.com/projects/j5 

public function show($id)
{
   return $id;   // will return 3
}