# Build.PL
use Module::Build;

my $class = Module::Build->subclass(
    class => "Module::Build::Custom",
    code => <<'SUBCLASS', );

    sub ACTION_install {
        my $self = shift;
        # YOUR CODE HERE
        $self->SUPER::ACTION_install;
    }
SUBCLASS
            
$class->new( 
    module_name         => 'Your::Module',
    # rest of the usual Module::Build parameters
)->create_build_script;