mojolicious: Can't use string ("json") as a HASH ref while "strict refs" in use

gistfile1.pl

Versions:
  
  CORE
  Perl        (v5.14.2, linux)
  Mojolicious (5.70, Tiger Face)

OPTIONAL
  EV 4.0+                 (not installed)
  IO::Socket::Socks 0.64+ (not installed)
  IO::Socket::SSL 1.84+   (1.999)
  Net::DNS::Native 0.14+  (not installed)
  
  
Code:
  use Mojo::Base 'Mojolicious';
  sub startup {
    my $self = shift;
    my $r = $self->routes;
    $r->get('/test')->render(json => {x => 3});
  }
  
Error at startup:
  Can't load application from file "/var/www/GGCC/script/test": Can't use string ("json") as a HASH ref while "strict refs" in use at /usr/local/share/perl/5.14.2/Mojolicious/Routes/Pattern.pm line 63.

you just can not "render" a "route", noob mistake