nix-pin: init at 0.1.2

pkgs/tools/package-management/nix-pin/default.nix

@@ -0,0 +1,32 @@
+{ pkgs, stdenv, fetchFromGitHub, mypy, python3 }:
+let self = stdenv.mkDerivation rec {
+  name = "nix-pin-${version}";
+  version = "0.1.2";
+  src = fetchFromGitHub {
+    owner = "timbertson";
+    repo = "nix-pin";
+    rev = "version-0.1.2";
+    sha256 = "1zwfb5198qzbjwivgiaxbwva9frgrrqaj92nw8vz95yi08pijssh";
+  };
+  buildInputs = [ python3 mypy ];
+  buildPhase = ''
+    mypy bin/*
+  '';
+  installPhase = ''
+    mkdir "$out"
+    cp -r bin share "$out"
+  '';
+  passthru = {
+    callWithPins = path: args:
+      import "${self}/share/nix/call.nix" {
+        inherit pkgs path args;
+      };
+  };
+  meta = with stdenv.lib; {
+    homepage = "https://github.com/timbertson/nix-pin";
+    description = "nixpkgs development utility";
+    license = licenses.mit;
+    maintainers = [ maintainers.timbertson ];
+    platforms = platforms.all;
+  };
+}; in self

pkgs/top-level/all-packages.nix

@@ -20509,6 +20509,8 @@ with pkgs;
 
   nix-index = callPackage ../tools/package-management/nix-index { };
 
+  nix-pin = callPackage ../tools/package-management/nix-pin { };
+
   inherit (callPackages ../tools/package-management/nix-prefetch-scripts { })
     nix-prefetch-bzr
     nix-prefetch-cvs