1 files changed, 22 insertions, 72 deletions
diff --git a/third_party/default.nix b/third_party/default.nix
index 774e634f9cef..0b1e94c7f86c 100644
--- a/third_party/default.nix
+++ b/third_party/default.nix
@@ -1,73 +1,23 @@
-# This file controls the import of external dependencies (i.e.
-# third-party code) into my package tree.
+# This file defines the root of all external dependency imports (i.e.
+# third-party code) in the TVL package tree.
 #
-# This includes *all packages needed from nixpkgs*.
-{ ... }:
-
-let
-  # Tracking nixos-unstable as of 2021-03-25.
-  nixpkgsCommit = "60dd94fb7e01a8288f6638eee71d7cb354c49327";
-  nixpkgsSrc = fetchTarball {
-    url = "https://github.com/NixOS/nixpkgs/archive/${nixpkgsCommit}.tar.gz";
-    sha256 = "0skdwk9bdld295kzrymirs8xrzycqmhsclaz8s18jhcz75hb8sk3";
-  };
-  nixpkgs = import nixpkgsSrc {
-    config.allowUnfree = true;
-    config.allowBroken = true;
-
-    # Lutris depends on p7zip, which is considered insecure.
-    config.permittedInsecurePackages = [
-      "p7zip-16.02"
-    ];
-  };
-
-  # Tracking nixos-20.09 as of 2021-03-25.
-  stableCommit = "223d0d733a66b46504ea6b4c15f88b7cc4db58fb";
-  stableNixpkgsSrc = fetchTarball {
-    url = "https://github.com/NixOS/nixpkgs/archive/${stableCommit}.tar.gz";
-    sha256 = "073327ris0frqa3kpid3nsjr9w8yx2z83xpsc24w898mrs9r7d5v";
-  };
-  stableNixpkgs = import stableNixpkgsSrc {};
-
-  exposed = import ./nixpkgs-exposed/exposed { inherit nixpkgs stableNixpkgs; };
-
-in exposed.lib.fix(self: exposed // {
-  callPackage = nixpkgs.lib.callPackageWith self;
-
-  # Provide the source code of nixpkgs, but do not provide an imported
-  # version of it.
-  inherit nixpkgsCommit nixpkgsSrc stableNixpkgsSrc;
-
-  # Expose upstream attributes so they can be overridden in readTree nodes
-  originals = {
-    inherit (nixpkgs) gtest openldap go grpc notmuch rr;
-    inherit (stableNixpkgs) git tdlib;
-    ffmpeg = nixpkgs.ffmpeg-full;
-    telega = stableNixpkgs.emacsPackages.telega;
-
-  };
-
-  # Use LLVM 11
-  llvmPackages = nixpkgs.llvmPackages_11;
-  clangStdenv = nixpkgs.llvmPackages_11.stdenv;
-  stdenv = nixpkgs.llvmPackages_11.stdenv;
-
-  clang-tools = (nixpkgs.clang-tools.override {
-    llvmPackages = nixpkgs.llvmPackages_11;
-  });
-
-  # Provide Emacs 27
-  #
-  # The assert exists because the name of the attribute is unversioned
-  # (which is different from previous versions).
-  emacs27 = assert ((exposed.lib.versions.major nixpkgs.emacs.version) == "27");
-    nixpkgs.emacs.overrideAttrs(old: {
-      configureFlags = old.configureFlags ++ [ "--with-cairo" ];
-    });
-
-  emacs27-nox = assert ((exposed.lib.versions.major nixpkgs.emacs.version) == "27");
-    nixpkgs.emacs-nox;
-
-  # Make NixOS available
-  nixos = import "${nixpkgsSrc}/nixos";
-})
+# There are two categories of third-party programs:
+#
+# 1) Programs in nixpkgs, the NixOS package set. For these, you might
+#    want to look at //third_party/nixpkgs (for the package set
+#    imports) and //third_party/overlays (for modifications in these
+#    imported package sets).
+#
+# 2) Third-party software packaged in this repository. This is all
+#    other folders below //third_party, other than the ones mentioned
+#    above.
+
+{ pkgs, ... }:
+
+{
+  # Expose a partially applied NixOS, expecting an attribute set with
+  # a `configuration` key. Exposing it like this makes it possible to
+  # modify some of the base configuration used by NixOS. passed to
+  # this.
+  nixos = import "${pkgs.path}/nixos";
+}