existing.js

'use strict';

module.exports = function (router) {
    
    // Register function under slugified function name: `my-foo-route`
    // Similar to `named.js`, the more I think about it not sure how this would work.
    router.get('/foo', function myFooRoute(req, res) {
        res.send('ok'); 
    });
    
};

// Only feasible by proxying `router`

named.js

'use strict';

module.exports = function (router) {
    
    // The more I think about it not sure how this would work.
    router.get('/foo', router.name('my-foo', function (req, res) {
        res.send('ok');
    }));
    
}

// Only feasible by proxying `router`

other.js

'use strict';

module.exports = function (router, registry) {
    
    router.get(registry.path('my-route', '/foo'), function (req, res) {
        res.send('ok');
    });
    
};

routify.js

'use strict';

module.exports = function (registry) {
    
    // Invocation of `registry` returns an instance of `express.Router`
    registry('my-route').get('/foo', function (req, res) {
        res.send('ok');
    });
    
};

// Only feasible by proxying router.