flare-signal-nixified: support defaultCrateOverrides

pkgs/additional/flare-signal-nixified/default.nix

@@ -6,6 +6,7 @@
 { lib
 , appstream-glib
 , blueprint-compiler
+, defaultCrateOverrides
 , desktop-file-utils
 , fetchFromGitLab
 , flare-signal
@@ -29,11 +30,7 @@
 , writeText
 }:
 let
-  cargoNix = import ./Cargo.nix {
+  extraCrateOverrides = {
-    inherit pkgs;
-
-    rootFeatures = [ ];  #< avoids --cfg feature="default", simplifying the rustc CLI so that i can pass it around easier
-    defaultCrateOverrides = pkgs.defaultCrateOverrides // {
     flare = attrs: attrs // {
       # inherit (flare-signal) src;
       src = fetchFromGitLab {
@@ -235,5 +232,16 @@ let
       '';
     };
   };
+
+  defaultCrateOverrides' = defaultCrateOverrides // (lib.mapAttrs (crate: fn:
+    # map each `extraCrateOverrides` to first pass their attrs through `defaultCrateOverrides`
+    attrs: fn ((defaultCrateOverrides."${crate}" or (a: a)) attrs)
+  ) extraCrateOverrides);
+
+  cargoNix = import ./Cargo.nix {
+    inherit pkgs;
+
+    rootFeatures = [ ];  #< avoids --cfg feature="default", simplifying the rustc CLI so that i can pass it around easier
+    defaultCrateOverrides = defaultCrateOverrides';
   };
 in cargoNix.workspaceMembers.flare.build