Try #1506:

Author: iohk-bors[bot]

ci.nix

@@ -11,6 +11,7 @@
   inherit (pkgs.haskell-nix) sources;
   nixpkgsVersions = {
     "R2111" = "nixpkgs-2111";
+    "R2205" = "nixpkgs-2205";
     "unstable" = "nixpkgs-unstable";
   };
   compilerNixNames = nixpkgsName: nixpkgs: builtins.mapAttrs (compiler-nix-name: runTests: {
@@ -26,6 +27,9 @@
     nixpkgs.lib.optionalAttrs (nixpkgsName == "R2111") {
       ghc865 = false;
       ghc8107 = true;
+    } // nixpkgs.lib.optionalAttrs (nixpkgsName == "R2205") {
+      ghc865 = false;
+      ghc8107 = true;
     } // nixpkgs.lib.optionalAttrs (nixpkgsName == "unstable") {
       ghc865 = false;
       ghc884 = false; # Native version is used to boot 9.0.1

flake.lock

@@ -6,6 +6,7 @@
     nixpkgs-2003 = { url = "github:NixOS/nixpkgs/nixpkgs-20.03-darwin"; };
     nixpkgs-2105 = { url = "github:NixOS/nixpkgs/nixpkgs-21.05-darwin"; };
     nixpkgs-2111 = { url = "github:NixOS/nixpkgs/nixpkgs-21.11-darwin"; };
+    nixpkgs-2205 = { url = "github:NixOS/nixpkgs/nixpkgs-22.05-darwin"; };
     nixpkgs-unstable = { url = "github:NixOS/nixpkgs/nixpkgs-unstable"; };
     flake-utils = { url = "github:numtide/flake-utils"; };
     hydra.url = "hydra";

flake.nix

@@ -1,7 +1,7 @@
 # 'supportedSystems' restricts the set of systems that we will evaluate for. Useful when you're evaluating
 # on a machine with e.g. no way to build the Darwin IFDs you need!
 { supportedSystems ? [ "x86_64-linux" "x86_64-darwin" ]
-, ifdLevel ? 3
+, ifdLevel ? 0
 , checkMaterialization ? false }:
 
 let