Build isync with oauth2 support natively

overlays/cyrus-sasl-oauth2.nix

@@ -1,24 +0,0 @@
-{ config, lib, pkgs, inputs, ... }:
-
-let
-  cyrus-sasl-xoauth2 = with pkgs;
-    stdenv.mkDerivation {
-      name = "cyrus-sasl-xoauth2";
-      src = inputs.cyrus-sasl-xoauth2;
-      nativeBuildInputs =
-        [ autoreconfHook inputs.nixpkgs.legacyPackages."${system}".cyrus_sasl ];
-    };
-
-in {
-  nixpkgs.overlays = [
-    (final: prev: {
-      patched-cyrus-sasl-oauth2 = prev.cyrus_sasl.overrideAttrs (div: rec {
-        postInstall = ''
-          for lib in ${cyrus-sasl-xoauth2}/lib/sasl2/*; do
-            ln -sf $lib $out/lib/sasl2/
-          done
-        '';
-      });
-    })
-  ];
-}

overlays/isync-oauth2.nix

@@ -1,14 +0,0 @@
-{ config, lib, pkgs, ... }:
-
-with pkgs;
-
-{
-
-  nixpkgs.overlays = [
-    (final: prev: {
-      isync-oauth2 = isync.overrideAttrs (div: rec {
-        buildInputs = [ openssl db patched-cyrus-sasl-oauth2 zlib ];
-      });
-    })
-  ];
-}