When mod_perl calls a handler it should be akin to a perl program calling the function "handler" in the referenced package... so I made a simple test case and tried it with parent:

-- t2.pm --
package t2;

sub testing2 { print "Testing from t2.pm\n"; }
1;

-- t.pm -- 
package t;
use parent t2;

sub testing { print "Testing from t.pm\n"; }
1;

-- t.pl --
#!/usr/bin/perl
use t;

t::testing();
t::testing2();
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Testing from t.pm
Undefined subroutine &t::testing2 called at ./t.pl line 5.
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use parent effects class methods, so you gotta use the -> operator to access them.

-- t.pm --
package t;

use parent qw(t2);

sub testing { print "Testing from t.pm\n"; }

1;

-- t2.pm --
package t2;

sub testing2 { print "Testing from t2.pm\n"; }

1;

-- test.pl --
#!/usr/bin/perl
use t;

t->testing();
t->testing2();
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Exporter is what you want if you want static functions:

-- t.pm --
package t;

use t2;

sub testing { print "Testing from t.pm\n"; }

1;

-- t2.pm --
package t2;

require Exporter;
our @ISA = qw(Exporter);
our @EXPORT = qw(testing2);
  
sub testing2 { print "Testing from t2.pm\n"; }

1;

-- test.pl --
#!/usr/bin/perl
use t;

t::testing();
t::testing2();
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Yeah the class methods don't jive with mod_perl at that level... but Exporter was spot on. I guess all this time I had been using it to import functions I never considered that it truly places them in the 'use'rs namespace. That's awesome and exactly what I needed. For anyone else that stumbles on this post in the future I ended up with something like:

package Basehandler;
BEGIN
  {
  use Exporter;
  our @ISA = qw (Exporter);
  our @EXPORT = qw (handler .... setup_environment );
  }

use Module::I::Always::Use::1;
  ...
use Module::I::Always::Use::35;

sub handler
  {
  ...  same 50 lines of code that do validation and then a jump table 
+to my real work functions ...
  }

sub setup_environment
  {
  ....
  }

-- MyHandler/ForThisEndpoint.pm --
package MyHandler::ForThisEndpoint;
use Basehandler;

sub work_function_1 {}
  ...
sub work_function_100 {}

-- MyHandler/ForAnotherEndpoint.pm --
package MyHandler::ForAnotherEndpoint;
use Basehandler;

sub work_function_1 {}
  ...
sub work_function_100 {}
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