reorganize Nix files to expose lib functions and derivations properly

default.nix

@@ -1,9 +1,4 @@
 { pkgs ? import <nixpkgs> {}}:
-rec {
-  yosys = pkgs.callPackage ./yosys.nix {};
-  symbiyosys = pkgs.symbiyosys.override { inherit yosys; };
-  nmigen = pkgs.callPackage ./nmigen.nix { inherit yosys; };
-  jtagtap = pkgs.callPackage ./jtagtap.nix { inherit nmigen; };
-  minerva = pkgs.callPackage ./minerva.nix { inherit nmigen; inherit jtagtap; };
-  heavycomps = pkgs.callPackage ./heavycomps.nix { inherit nmigen; };
+(import ./derivations.nix { inherit pkgs; }) // {
+	vivado = import ./vivado.nix { inherit pkgs; };
 }

derivations.nix

@@ -0,0 +1,9 @@
+{ pkgs }:
+rec {
+  yosys = pkgs.callPackage ./yosys.nix {};
+  symbiyosys = pkgs.symbiyosys.override { inherit yosys; };
+  nmigen = pkgs.callPackage ./nmigen.nix { inherit yosys; };
+  jtagtap = pkgs.callPackage ./jtagtap.nix { inherit nmigen; };
+  minerva = pkgs.callPackage ./minerva.nix { inherit nmigen; inherit jtagtap; };
+  heavycomps = pkgs.callPackage ./heavycomps.nix { inherit nmigen; };
+}

release.nix

@@ -0,0 +1,5 @@
+{ pkgs ? import <nixpkgs> {}}:
+let
+  derivations = import ./derivations.nix { inherit pkgs; };
+in
+  builtins.mapAttrs (name: value: pkgs.lib.hydraJob value) derivations

vivado.nix

@@ -22,7 +22,7 @@ let
   };
 in
   {
-    buildBitstream = { name, src, vivadoPath ? "/opt/Xilinx/Vivado/2018.3" }:
+    buildBitstream = { name, src, vivadoPath ? "/home/sb/opt/Xilinx/Vivado/2018.3" }:
       pkgs.stdenv.mkDerivation {
         inherit name src;
         phases = [ "buildPhase" ];