Add hydra.json and jobsets.nix for hydra

default.nix

@@ -36,9 +36,10 @@ let
       then pkgs.lib.composeExtensions orig.overrides overlay
       else overlay;
   };
-  
+
 in {
   haskellPackages =
     pkgs.haskell.packages.${compiler}.override overrideHaskellPackages;
   inherit pkgs;
+  nixpkgs = pkgs;
 }

hydra.json

@@ -0,0 +1,29 @@
+{
+  "enabled": 1,
+  "hidden": true,
+  "description": "Jobsets",
+  "nixexprinput": "src",
+  "nixexprpath": "jobsets.nix",
+  "checkinterval": 300,
+  "schedulingshares": 100,
+  "enableemail": false,
+  "emailoverride": "",
+  "keepnr": 10,
+  "inputs": {
+    "src": {
+      "type": "git",
+      "value": "https://github.com/haskell-nix/hnix-store.git master 1",
+      "emailresponsible": false
+    },
+    "nixpkgs": {
+      "type": "git",
+      "value": "https://github.com/NixOS/nixpkgs-channels nixos-unstable",
+      "emailresponsible": false
+    },
+    "prs": {
+      "type": "githubpulls",
+      "value": "haskell-nix hnix-store",
+      "emailresponsible": false
+    }
+  }
+}

jobsets.nix

@@ -0,0 +1,66 @@
+{ prs }:
+
+let
+  self = import ./. {};
+  pkgs = self.nixpkgs;
+  mkFetchGithub = value: {
+    inherit value;
+    type = "git";
+    emailresponsible = false;
+  };
+in
+with pkgs.lib;
+let
+  defaults = jobs: {
+    inherit (jobs) description;
+    enabled = 1;
+    hidden = false;
+    keepnr = 10;
+    schedulingshares = 100;
+    checkinterval = 120;
+    enableemail = false;
+    emailoverride = "";
+    nixexprinput = "hnix-store";
+    nixexprpath = "release.nix";
+    inputs = jobs.inputs // {
+      nixpkgs = {
+        type = "git";
+        value = "https://github.com/NixOS/nixpkgs-channels nixos-unstable";
+        emailresponsible = false;
+      };
+    };
+  };
+  branchJobset = branch: defaults {
+    description = "hnix-store-${branch}";
+    inputs = {
+      hnix-store = {
+        value = "https://github.com/haskell-nix/hnix-store ${branch}";
+        type = "git";
+        emailresponsible = false;
+      };
+    };
+  };
+  makePr = num: info: {
+    name = "hnix-store-pr-${num}";
+    value = defaults {
+      description = "#${num}: ${info.title}";
+      inputs = {
+        hnix-store = {
+          #NOTE: This should really use "pull/${num}/merge"; however, GitHub's
+          #status checks only operate on PR heads.  This creates a race
+          #condition, which can currently only be solved by requiring PRs to be
+          #up to date before they're merged.  See
+          #https://github.com/isaacs/github/issues/1002
+          value = "https://github.com/haskell-nix/hnix-store pull/${num}/head 1";
+          type = "git";
+          emailresponsible = false;
+        };
+      };
+    };
+  };
+  processedPrs = mapAttrs' makePr (builtins.fromJSON (builtins.readFile prs));
+  jobsetsAttrs = processedPrs //
+    genAttrs ["master" "pending"] branchJobset;
+in {
+  jobsets = pkgs.writeText "spec.json" (builtins.toJSON jobsetsAttrs);
+}