diff --git a/modules/default.nix b/modules/default.nix
index eb0daa3c9fe0..9bc43df1c5ff 100644
--- a/modules/default.nix
+++ b/modules/default.nix
@@ -18,7 +18,7 @@ let
     let
       f = w: x: builtins.trace "warning: ${w}" x;
     in
-    lib.fold f res res.config.warnings;
+    lib.foldr f res res.config.warnings;
 
   extendedLib = import ./lib/stdlib-extended.nix lib;
 
diff --git a/modules/misc/nixpkgs-disabled.nix b/modules/misc/nixpkgs-disabled.nix
index 5388026ed67a..daf51c3a219d 100644
--- a/modules/misc/nixpkgs-disabled.nix
+++ b/modules/misc/nixpkgs-disabled.nix
@@ -46,7 +46,7 @@ let
         traceXIfNot = c: if c x then true else lib.traceSeqN 1 x false;
       in
       traceXIfNot isConfig;
-    merge = args: lib.fold (def: mergeConfig def.value) { };
+    merge = args: lib.foldr (def: mergeConfig def.value) { };
   };
 
   # Copied from nixpkgs.nix.
diff --git a/modules/misc/nixpkgs.nix b/modules/misc/nixpkgs.nix
index d6963610b55e..d7a4bf301681 100644
--- a/modules/misc/nixpkgs.nix
+++ b/modules/misc/nixpkgs.nix
@@ -43,7 +43,7 @@ let
         traceXIfNot = c: if c x then true else lib.traceSeqN 1 x false;
       in
       traceXIfNot isConfig;
-    merge = args: lib.fold (def: mergeConfig def.value) { };
+    merge = args: lib.foldr (def: mergeConfig def.value) { };
   };
 
   overlayType = lib.mkOptionType {
diff --git a/modules/services/udiskie.nix b/modules/services/udiskie.nix
index 18f9fdaf99f3..c878bc8cacde 100644
--- a/modules/services/udiskie.nix
+++ b/modules/services/udiskie.nix
@@ -11,7 +11,7 @@ let
     types
     ;
 
-  mergeSets = sets: lib.lists.fold lib.attrsets.recursiveUpdate { } sets;
+  mergeSets = sets: lib.lists.foldr lib.attrsets.recursiveUpdate { } sets;
 
   yaml = pkgs.formats.yaml { };
 
diff --git a/modules/services/way-displays.nix b/modules/services/way-displays.nix
index 1ddfe19daaad..9e759b95131d 100644
--- a/modules/services/way-displays.nix
+++ b/modules/services/way-displays.nix
@@ -17,7 +17,7 @@ let
     mkOption
     types
     ;
-  mergeSets = sets: lists.fold attrsets.recursiveUpdate { } sets;
+  mergeSets = sets: lists.foldr attrsets.recursiveUpdate { } sets;
   cfg = config.services.way-displays;
   yaml = pkgs.formats.yaml { };
 in