emacsPackages.alectryon: override only when needed

        # https://github.com/gongo/airplay-el/issues/2

        airplay = addPackageRequires super.airplay [ self.request-deferred ];

        alectryon = super.alectryon.overrideAttrs (

          finalAttrs: previousAttrs: {

            # https://github.com/melpa/melpa/pull/9185

        alectryon = super.alectryon.overrideAttrs (old: {

            preBuild =

            old.preBuild or ""

              if lib.versionOlder finalAttrs.version "20241006.1902" then

                previousAttrs.preBuild or ""

                + "\n"

                + ''

                  rm --recursive --verbose etc/elisp/screenshot

            '';

        });

                ''

              else

                previousAttrs.preBuild or null;

          }

        );

        # https://github.com/gergelypolonkai/alert-termux/issues/2

        alert-termux = addPackageRequires super.alert-termux [ self.alert ];