package MyApp::Model::ProblemSolver;
use Moose;
use namespace::autoclean;

extends 'Catalyst::Model::Factory::PerRequest';

__PACKAGE__->config(
  class => 'MyNonCatalyst::ProblemSolver',
);

# provide arguments as a list  instead of hash-ref
sub mangle_arguments {
  my ($self, $args) = @_;
  return %$args;
}

##</code><code>##

override 'prepare_arguments' => sub {
  my ($self, $c) = @_; 
  my $config_params = super();
  my $passed_in_params = $c->stash->{problem_solver_args};
  my %merged_args = ( %$config_params, %$passed_in_params ); 
  return \%merged_args;
}; # prepare_arguments

##</code><code>##


$c->stash->{problem_solver_args}{some_param} = $user_input1 if $user_input1;
$c->stash->{problem_solver_args}{some_other_param} = $user_input2;

my $problem_solver = $c->model('ProblemSolver');
my $result = $problem_solver->solve_problem();

##</code><code>##

Model::ProblemSolver:
  args:
    database: a_database_of_solved_problems
    some_param: SOME_DEFAULT_VALUE