meta: Replace joshuto package with overlay

This actually took *forever*, but now that I know how to write nixpkgs
overlays, any future ones I write should be relatively straight-forward.

modules/joshuto/default.nix

@@ -1,6 +1,6 @@
 {pkgs, ...}: {
-  environment.systemPackages = [
-    (pkgs.callPackage ../../packages/joshuto {})
+  environment.systemPackages = with pkgs; [
+    joshuto
   ];
 
   home-manager.sharedModules = [

overlays/default.nix

@@ -0,0 +1,21 @@
+{lib, ...}: {
+  nixpkgs.overlays = [
+    (final: prev: {
+      joshuto = prev.joshuto.overrideAttrs (oldAttrs: rec {
+        version = "493af3185092036cbbae81ae620b101f66cf4e9a";
+        src = final.fetchFromGitHub {
+          owner = "kamiyaa";
+          repo = "joshuto";
+          rev = "493af3185092036cbbae81ae620b101f66cf4e9a";
+          sha256 = "sha256-jLlDMV03eFWDB1D6pFEq2MFAfoVwFTy8ZpweS9syDB0=";
+        };
+
+        cargoDeps = oldAttrs.cargoDeps.overrideAttrs (lib.const {
+          name = "joshuto.tar.gz";
+          inherit src;
+          outputHash = "sha256-cDy7sccuZj+RNjaDGjqczGl//zgmMAifjv/ZMEO/yyY=";
+        });
+      });
+    })
+  ];
+}

packages/joshuto/default.nix

@@ -1,25 +0,0 @@
-{
-  lib,
-  rustPlatform,
-  fetchFromGitHub,
-}:
-rustPlatform.buildRustPackage rec {
-  pname = "joshuto";
-  version = "493af3185092036cbbae81ae620b101f66cf4e9a";
-
-  src = fetchFromGitHub {
-    owner = "kamiyaa";
-    repo = pname;
-    rev = version;
-    sha256 = "sha256-jLlDMV03eFWDB1D6pFEq2MFAfoVwFTy8ZpweS9syDB0=";
-  };
-
-  cargoSha256 = "sha256-dffKMgXhm4VpDSEzFW5d4oGCBKY/ppj1gx29Iw3Msc8=";
-
-  meta = with lib; {
-    description = "Ranger-like terminal file manager written in Rust";
-    homepage = "https://github.com/kamiyaa/joshuto";
-    license = licenses.lgpl3Only;
-    maintainers = with maintainers; [figsoda totoroot];
-  };
-}

src/main.nix

@@ -9,6 +9,7 @@
 in {
   imports = [
     "${VARIABLES.hostHardwareConfiguration}"
+    ../overlays
     ../modules
     ../containers/rar.nix
     ../containers/wine.nix