Cannot build !

I cannot build my app... Lost 3 days searching :(, so any help is welcome !

Something must be wrong with steal.build code or doc (or more probably with my code)

If I do not use packages, with something like :

1. steal('jquery', 'app/ctrl/main', 'app/ctrl/login', 'model/server',
2. function($, Main, Login, Server) {
3.   $(document).ready(function() {
4.     Server.ping(function(usr) {
5.       new Main('#container', {user: usr});
6.     },
7.     function(jqXHR, textStatus, errorThrown) {
8.       new Login('#container', {});
9.     });
10. });
    

No package is created.
Production.js contains only:

1. steal.packages({});
   

If I use packages (following the way the doc tells, I think) with something like :

1. steal.packages('app/ctrl/main', 'app/ctrl/login');
   
   steal('jquery', 'model/server',
   function($, Server) {
   
     // =====================
   
     $(document).ready(function() {
       Server.ping(function(usr) {
         steal('app/ctrl/main', function(Main) {
           new Main('#container', {user: usr});
         });
   
       },
       function(jqXHR, textStatus, errorThrown) {
         steal('app/ctrl/login', function(Login) {
           new Login('#container', {});
         });
   
       });
     });
   
   });
   

The packages are created, but only the production.js is loaded. Nothing appends id prod mode.

==> In both cases, dev mode runs ok.

Can you tell me what can generate this behavior ? How can I go further in looking for my mistakes ?

Thanks for help.