Build using the nix flake

flake.lock

@@ -1,6 +1,16 @@
 {
     "nonFlakeRequires": {},
     "requires": {
+        "nix": {
+            "contentHash": "sha256-rUM0KiuCRHv8WKBOfv4XKOu7WP8nsYdPdnTPZFBzjyc=",
+            "requires": {
+                "nixpkgs": {
+                    "contentHash": "sha256-vy2UmXQM66aS/Kn2tCtjt9RwxfBvV+nQVb5tJQFwi8E=",
+                    "uri": "github:edolstra/nixpkgs/a4d896e89932e873c4117908d558db6210fa3b56"
+                }
+            },
+            "uri": "github:NixOS/nix/3cecf3f39c5c580ed6d0c5f0bcbb09dcc53dfae4"
+        },
         "nixpkgs": {
             "contentHash": "sha256-vy2UmXQM66aS/Kn2tCtjt9RwxfBvV+nQVb5tJQFwi8E=",
             "uri": "github:edolstra/nixpkgs/a4d896e89932e873c4117908d558db6210fa3b56"

flake.nix

@@ -5,13 +5,16 @@
 
   epoch = 2019;
 
-  requires = [ "nixpkgs" ];
+  requires = [ "nixpkgs" "nix" ];
 
   provides = deps: rec {
 
     hydraJobs = import ./release.nix {
       hydraSrc = deps.self;
       nixpkgs = deps.nixpkgs;
+      nix = deps.nix.provides.hydraJobs.build.x86_64-linux // {
+        perl-bindings = deps.nix.provides.hydraJobs.perlBindings.x86_64-linux;
+      };
     };
 
     packages.hydra = hydraJobs.build.x86_64-linux;

release.nix

@@ -2,14 +2,14 @@
 , nixpkgs ? builtins.fetchGit { url = https://github.com/NixOS/nixpkgs-channels.git; ref = "nixos-19.03-small"; }
 , officialRelease ? false
 , shell ? false
+, pkgs ? import nixpkgs { system = "x86_64-linux"; }
+, nix ? pkgs.nixUnstable or pkgs.nix
 }:
 
-with import (nixpkgs + "/lib");
+with pkgs.lib;
 
 let
 
-  pkgs = import nixpkgs { system = "x86_64-linux"; };
-
   genAttrs' = genAttrs [ "x86_64-linux" /* "i686-linux" */ ];
 
   hydraServer = hydraPkg:
@@ -44,8 +44,6 @@ rec {
 
     let
 
-      nix = pkgs.nixUnstable or pkgs.nix;
-
       perlDeps = buildEnv {
         name = "hydra-perl-deps";
         paths = with perlPackages;