OK, so an update here. I have removed the fork() stuff. The problem is that when I create an object in my webapp, it goes out of scope immediately as the webapp is presented with plackup. Here's a much trimmed down repro example:

# Scope.pm in webapp root dir

package Scope;

sub new {
    return bless {}, shift
}

sub DESTROY {
    print "going out of scope...\n";
}

# webapp

package MyApp;

use lib '.';
use Scope;
use Dancer2;
use Dancer2::Plugin::Database;

our $VERSION = '0.1';

my $obj = Scope->new;
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Now run it:

plackup -R lib,bin bin/app.pl
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Here's what happens when I run it:

Watching lib bin bin/lib bin/app.pl for file updates.
going out of scope
HTTP::Server::PSGI: Accepting connections at http://0:5000/
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I've also asked for guidance on the #dancer IRC channel. I'm hoping someone with experience with Dancer2 (or perhaps web frameworks in general) can help me get a grasp on getting around this issue (as I pour through resources I'm finding online elsewhere).