Add nix files

default.nix

@@ -0,0 +1,35 @@
+{
+  pkgs ? import <nixpkgs> { },
+}:
+
+pkgs.rustPlatform.buildRustPackage {
+  pname = "pile";
+  version = "0.0.1";
+  src = ./.;
+
+  cargoLock.lockFile = ./Cargo.lock;
+
+  buildInputs = [
+    pkgs.pdfium-binaries
+    pkgs.openssl
+  ]
+  ++ pkgs.lib.optionals pkgs.stdenv.isDarwin [
+    pkgs.darwin.apple_sdk.frameworks.Security
+    pkgs.darwin.apple_sdk.frameworks.SystemConfiguration
+  ];
+
+  nativeBuildInputs = [
+    pkgs.pkg-config
+    pkgs.makeWrapper
+  ];
+
+  postInstall = ''
+    wrapProgram $out/bin/pile \
+      --prefix LD_LIBRARY_PATH : ${pkgs.lib.makeLibraryPath [ pkgs.pdfium-binaries ]}
+  '';
+
+  meta = {
+    description = "pile - flexible file indexing";
+    mainProgram = "pile";
+  };
+}