There are many ways to build web apps with Perl nowadays. To me, it all depends where you're going to deploy your app, what does your server provider offer, what you're load is going to be, etc. Start with the 3 shiniest Perl web frameworks right now: Catalyst, Dancer and Mojolicious. All 3 can accommodate the tiniest app, but can grow with it in case you're app skyrockets in functionality.

For instance, a simple Dancer program as such could get you started (from Dancer::Tutorial):

# myapp.pl 
  use Dancer;

  get '/' => sub {
        return 'Hello World!';
  };

  start;
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Install Dancer if you haven't done so already:

$ cpan Dancer
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Then just fire off the built-in server from the command line:

$ perl myapp.pl
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And take your browser to http://localhost:3000.

For a full blown application with templates and configuration files, use the Dancer app starter:

$ dancer -a myapp
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