Although I mentioned a caveat when debugging web applications, our Apps at Work all adhere to the Perl Web Server Gateway Interface (PSGI) specification and thus we can use tools like Test::WWW::Mechanize::PSGI or Plack::Test to run tests and debugging sessions in the same Perl process ... Just to be sure (and to demonstrate some other cool debugger features), let's set another breakpoint while in the debugger and then exercise that route again ... Note that because we'Re using PSGI, we were able to set breakpoints in our web App code itself and the debugger stopped there and enabled US to have a LOOK around.