Add inspekt3d to guile deps, and reorganize

I reorganized in order to debug a problem with the nix overlays. I think
having small, focused overlayes is more understandable than one overlay
that references itself via `rec`. Also the error traces are easier to
follow with smaller overlays.

1 files changed, 30 insertions, 13 deletions

diff --git a/Biz/Bild/Nixpkgs.nix b/Biz/Bild/Nixpkgs.nix
index 88cf6ca..ffafe3f 100644
--- a/Biz/Bild/Nixpkgs.nix
+++ b/Biz/Bild/Nixpkgs.nix
@@ -1,16 +1,33 @@
 let
   sources = import ./Sources.nix;
-  nixpkgs = import sources.nixpkgs {
-    system = __currentSystem;
-    overlays = [
-      (_: _: { inherit sources; })
-      (import ./Overlay.nix)
-      (_: pkgs: pkgs.overridePinnedDeps pkgs.overrideSource)
-      (_: _: { niv = import sources.niv {}; })
-      (_: pkgs: { wemux = pkgs.callPackage ./Wemux.nix {}; })
-    ];
-    config = {
-      allowBroken = true;
-    };
+in
+import sources.nixpkgs {
+  system = __currentSystem;
+  overlays = [
+    (_: _: { inherit sources; })
+    (_: pkgs: rec {
+      pinnedDeps = builtins.attrNames
+        (builtins.removeAttrs pkgs.sources ["__functor"]);
+
+      overridePinnedDeps = builder: pkgs.lib.genAttrs pinnedDeps builder;
+
+      # Modifies a derivation with our source and version, keeping old build
+      # rules. This will fail if build steps have changed, or if no build
+      # rules are available upstream..
+      overrideSource = depName:
+        if pkgs ? depName then
+          pkgs.${depName}.overrideAttrs (old: old // rec {
+            name = "${depName}-${version}";
+            version = pkgs.sources.${depName}.version or pkgs.sources.${depName}.rev;
+            src = pkgs.sources.${depName};
+          })
+        else null;
+    })
+    (_: pkgs: pkgs.overridePinnedDeps pkgs.overrideSource)
+    (import ./Deps.nix)
+    (_: pkgs: { niv = import pkgs.sources.niv {}; })
+  ];
+  config = {
+    allowBroken = true;
   };
-in nixpkgs
+}