woot, back up and running, the error was not at al related to nixvim...

packages/everforest-gtk/default.nix

@@ -1,69 +0,0 @@
-{
-  lib,
-  stdenv,
-  fetchFromGitHub,
-  gtk-engine-murrine,
-  jdupes,
-  sassc,
-  accent ? ["default"],
-  shade ? "dark",
-  size ? "standard",
-}: let
-  validAccents = ["default" "purple" "pink" "red" "orange" "yellow" "green" "teal" "grey"];
-  validShades = ["light" "dark"];
-  validSizes = ["standard" "compact"];
-
-  single = x: lib.optional (x != null) x;
-  pname = "Everforest";
-in
-  lib.checkListOfEnum "${pname} Valid theme accent(s)" validAccents accent
-  lib.checkListOfEnum "${pname} Valid shades" validShades (single shade)
-  lib.checkListOfEnum "${pname} Valid sizes" validSizes (single size)
-
-  stdenv.mkDerivation {
-    pname = "${pname}";
-    version = "0-unstable-2024-06-27";
-
-    src = fetchFromGitHub {
-      owner = "Fausto-Korpsvart";
-      repo = "Everforest-GTK-Theme";
-      rev = "bb3fc27a2468f0965a738d9d3b30c52a799572d2";
-      hash = "sha256-sTHyH1pCq/d2JMmEppdQAc+P8a3y1lM+WQcW7nXEoPE=";
-    };
-
-    nativeBuildInputs = [jdupes sassc];
-
-    propagatedUserEnvPkgs = [gtk-engine-murrine];
-
-    postPatch = ''
-      find -name "*.sh" -print0 | while IFS= read -r -d ''' file; do
-        patchShebangs "$file"
-      done
-    '';
-
-    dontBuild = true;
-
-    installPhase = ''
-      runHook preInstall
-
-      mkdir -p $out/share/themes
-
-      ./themes/install.sh \
-        --name ${pname} \
-        ${toString (map (x: "--theme " + x) accent)} \
-        ${lib.optionalString (shade != null) ("--color " + shade)} \
-        ${lib.optionalString (size != null) ("--size " + size)} \
-        --dest $out/share/themes
-
-      jdupes --quiet --link-soft --recurse $out/share
-
-      runHook postInstall
-    '';
-
-    meta = with lib; {
-      description = "A GTK theme based on the Everforest colour palette";
-      homepage = "https://github.com/Fausto-Korpsvart/Everforest-GTK-Theme";
-      license = licenses.gpl3Only;
-      platforms = platforms.all;
-    };
-  }