Set evalSystem to linux for nix-tools hydra jobs

Author: hamishmack

nix-tools/flake.nix

@@ -78,7 +78,7 @@
       hydraJobs = forAllSystems
         (pkgs:
           # project's hydraJobs
-          pkgs.nix-tools.project.flake'.hydraJobs
+          pkgs.nix-tools-unchecked.project.flake'.hydraJobs
           # tarballs with static builds.
           // lib.optionalAttrs (pkgs.buildPlatform.system == "x86_64-linux")
             { binary-tarball = mkTarball pkgs.pkgsCross.musl64; }

nix-tools/overlay.nix

@@ -23,7 +23,7 @@ let
             # tests need to fetch hackage
             configureArgs = final.lib.mkDefault "--disable-tests";
 
-            evalPackages = final.buildPackages;
+            evalSystem = builtins.currentSystem or "x86_64-linux";
 
             # Tools to include in the development shell
             shell.tools.cabal = "latest";