Reorganize and update nixpkgs upstreams

This patch does a few things:

1. Switches from nixpkgs-unstable to nixos-unstable{,-small}, simply because
   nixpkgs-unstable is not in cache.nixos.org, but nixos-unstable is, and -small
   is the same but requires all tests to pass. So we should prefer
   nixos-unstable-small, whenever possible.

2. Reorganizes the nixpkgs import code such that Nixpkgs.nix returns an attrset
   of all the nixpkgs that I want to use, rather than putting other nixpkgs
   branches into the main one as an overlay. This is much simpler and explicit,
   but it meant I had to change a lot of usages throughtout the nix codebase.

3. As a consequence of 2, moves the overlays into separate files so they can be
   re-used across nixpkgs branches.

1 files changed, 23 insertions, 0 deletions

diff --git a/Biz/Bild/Python.nix b/Biz/Bild/Python.nix
new file mode 100644
index 0000000..51f35f1
--- /dev/null
+++ b/Biz/Bild/Python.nix
@@ -0,0 +1,23 @@
+_self: super: {
+  python3 = super.python3.override {
+    packageOverrides = _pyself: pysuper:
+      with pysuper.pkgs.python3Packages;
+      let dontCheck = p: p.overridePythonAttrs (_: { doCheck = false; });
+      in {
+        exllama = callPackage ./Deps/exllama.nix {
+          cudaPackages = super.pkgs.cudaPackages_11_7;
+        };
+        exllamav2 = callPackage ./Deps/exllamav2.nix {
+          cudaPackages = super.pkgs.cudaPackages_11_7;
+        };
+        interegular = callPackage ./Deps/interegular.nix { };
+        mypy = dontCheck pysuper.mypy;
+        outlines = callPackage ./Deps/outlines.nix { };
+        perscache = callPackage ./Deps/perscache.nix { };
+        safetensors = super.nixos-23_11.python310Packages.safetensors.override {
+          buildPythonPackage = pysuper.pkgs.python3Packages.buildPythonPackage;
+        };
+        tokenizers = dontCheck pysuper.tokenizers;
+      };
+  };
+}