chore: move to crane for building the package

Crane makes it easier to reuse artifacts when building multiple features
at the same time.

(almost) scientific test showed reduction of build time from ~5 minutes
(naersk) to ~2 (crane).

This should not change user experience.

flake.nix

@@ -7,7 +7,21 @@
     flake-parts.url = "github:hercules-ci/flake-parts";
     devshell.url = "github:numtide/devshell";
     # Utils for building Rust stuff
-    naersk.url = "github:nmattia/naersk/master";
+
+    crane = {
+      url = "github:ipetkov/crane";
+      inputs.nixpkgs.follows = "nixpkgs";
+    };
+    # fenix = {
+    #   url = "github:nix-community/fenix";
+    #   inputs.nixpkgs.follows = "nixpkgs";
+    #   inputs.rust-analyzer-src.follows = "";
+    # };
+    # advisory-db = {
+    #   url = "github:rustsec/advisory-db";
+    #   flake = false;
+    # };
+
     # The Rust source for xremap
     xremap = {
       url = "github:k0kubun/xremap?ref=v0.8.12";
@@ -39,11 +53,11 @@
         ];
         perSystem = { config, self', inputs', pkgs, system, ... }:
           let
-            naersk-lib = pkgs.callPackage inputs.naersk { };
+            craneLib = inputs.crane.lib.${system};
           in
           {
             formatter = pkgs.nixpkgs-fmt;
-            packages = import ./overlay { inherit (inputs) xremap; inherit naersk-lib pkgs; };
+            packages = import ./overlay { inherit (inputs) xremap; inherit craneLib pkgs; };
             # This way all packages get immediately added to the overlay except for the one called literally called "default"
             overlayAttrs = builtins.removeAttrs config.packages [ "default" ];
             devshells.default = {

overlay/default.nix

@@ -1,16 +1,30 @@
 # Overlay file that contains the definition of building a package
-{ xremap, naersk-lib, pkgs }:
+{ xremap, craneLib, pkgs }:
 let
-  packageWithFeature = feature: naersk-lib.buildPackage {
-    root = xremap;
-    cargoBuildOptions = (x: x ++ pkgs.lib.optional (feature != null) "--features ${feature}");
+  commonArgs = {
+    src = xremap;
+    strictDeps = true;
+
+    buildInputs = [
+      # Add additional build inputs here
+    ];
+
+    # Additional environment variables can be set directly
+    # MY_CUSTOM_VAR = "some value";
+  };
+  cargoArtifacts = craneLib.buildDepsOnly commonArgs;
+
+  packageWithFeature = feature: craneLib.buildPackage (commonArgs // {
+    inherit cargoArtifacts;
+    cargoExtraArgs = "--locked${if (feature != null) then " --features ${feature}"  else ""}";
+    # cargoBuildOptions = (x: x ++ pkgs.lib.optional (feature != null) "--features ${feature}");
     # The following two options are for introspection to be able to see if sway/gnome were actually pulled in
     # To see that - visually inspect the deps directory inside result/target/ and check for swayipc/zbus
     # See cargo.toml for feature-specific deps
-    copyTarget = true;
-    compressTarget = false;
+    # copyTarget = true;
+    # compressTarget = false;
     meta.mainProgram = "xremap";
-  };
+  });
 in
 rec {
   # No features