static compilation wiith musl and nix for linux systems

.gitignore

@@ -4,3 +4,4 @@
 node_modules
 /target
 nzz/
+result

flake.lock

@@ -37,6 +37,25 @@
         "type": "github"
       }
     },
+    "naersk": {
+      "inputs": {
+        "nixpkgs": "nixpkgs_2"
+      },
+      "locked": {
+        "lastModified": 1718727675,
+        "narHash": "sha256-uFsCwWYI2pUpt0awahSBorDUrUfBhaAiyz+BPTS2MHk=",
+        "owner": "nix-community",
+        "repo": "naersk",
+        "rev": "941ce6dc38762a7cfb90b5add223d584feed299b",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-community",
+        "ref": "master",
+        "repo": "naersk",
+        "type": "github"
+      }
+    },
     "nixpkgs": {
       "locked": {
         "lastModified": 1719690277,
@@ -54,6 +73,18 @@
       }
     },
     "nixpkgs_2": {
+      "locked": {
+        "lastModified": 0,
+        "narHash": "sha256-H3+EC5cYuq+gQW8y0lSrrDZfH71LB4DAf+TDFyvwCNA=",
+        "path": "/nix/store/j4jzjbr302cw5bl0n3pch5j9bh5qwmaj-source",
+        "type": "path"
+      },
+      "original": {
+        "id": "nixpkgs",
+        "type": "indirect"
+      }
+    },
+    "nixpkgs_3": {
       "locked": {
         "lastModified": 1719075281,
         "narHash": "sha256-CyyxvOwFf12I91PBWz43iGT1kjsf5oi6ax7CrvaMyAo=",
@@ -73,7 +104,8 @@
       "inputs": {
         "fenix": "fenix",
         "flake-utils": "flake-utils",
-        "nixpkgs": "nixpkgs_2"
+        "naersk": "naersk",
+        "nixpkgs": "nixpkgs_3"
       }
     },
     "rust-analyzer-src": {

flake.nix

@@ -1,8 +1,10 @@
+# thanks to https://code.betamike.com/micropelago/domani for the flake, I still do not completely understand it :) 
 {
   description = "little-hesinde project";
   inputs = {
     nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
     flake-utils.url = "github:numtide/flake-utils";
+    naersk.url = "github:nix-community/naersk/master";
     fenix.url = "github:nix-community/fenix";
   };
 
@@ -10,14 +12,69 @@
     {
       nixpkgs,
       flake-utils,
+      naersk,
       fenix,
       ...
     }:
+    let
+      mkToolchain =
+        fenixPkgs:
+        fenixPkgs.fromToolchainFile {
+          file = ./rust-toolchain.toml;
+          sha256 = "sha256-Ngiz76YP4HTY75GGdH2P+APE/DEIx2R/Dn+BwwOyzZU=";
+        };
+
+      buildTargets = {
+        "x86_64-linux" = {
+          crossSystemConfig = "x86_64-unknown-linux-musl";
+          rustTarget = "x86_64-unknown-linux-musl";
+        };
+
+        "i686-linux" = {
+          crossSystemConfig = "i686-unknown-linux-musl";
+          rustTarget = "i686-unknown-linux-musl";
+        };
+
+        "aarch64-linux" = {
+          crossSystemConfig = "aarch64-unknown-linux-musl";
+          rustTarget = "aarch64-unknown-linux-musl";
+        };
+      };
+
+      eachSystem =
+        supportedSystems: callback:
+        builtins.foldl' (overall: system: overall // { ${system} = callback system; }) { } supportedSystems;
+
+      eachCrossSystem =
+        supportedSystems: callback:
+        eachSystem supportedSystems (
+          buildSystem:
+          builtins.foldl' (
+            inner: targetSystem: inner // { "cross-${targetSystem}" = callback buildSystem targetSystem; }
+          ) { default = callback buildSystem buildSystem; } supportedSystems
+        );
+
+      mkPkgs =
+        buildSystem: targetSystem:
+        import nixpkgs (
+          {
+            system = buildSystem;
+          }
+          // (
+            if targetSystem == null then
+              { }
+            else
+              { crossSystem.config = buildTargets.${targetSystem}.crossSystemConfig; }
+          )
+        );
+
+    in
     flake-utils.lib.eachDefaultSystem (
       system:
       let
         pkgs = import nixpkgs { inherit system; };
-        rust = fenix.packages.${system}.stable;
+        toolchain = mkToolchain fenix.packages.${system};
+
       in
       {
         devShells.default =
@@ -25,11 +82,62 @@
           mkShell {
             buildInputs = [
               geckodriver
-              rust.toolchain
+              toolchain
               cargo-deny
               rust-analyzer
             ];
           };
       }
-    );
+    )
+    // {
+      packages = eachCrossSystem (builtins.attrNames buildTargets) (
+        buildSystem: targetSystem:
+        let
+          pkgs = mkPkgs buildSystem null;
+          pkgsCross = mkPkgs buildSystem targetSystem;
+          rustTarget = buildTargets.${targetSystem}.rustTarget;
+
+          fenixPkgs = fenix.packages.${buildSystem};
+          toolchain = mkToolchain fenixPkgs;
+
+          buildPackageAttrs =
+            if builtins.hasAttr "makeBuildPackageAttrs" buildTargets.${targetSystem} then
+              buildTargets.${targetSystem}.makeBuildPackageAttrs pkgsCross
+            else
+              { };
+
+          naersk-lib = pkgs.callPackage naersk {
+            cargo = toolchain;
+            rustc = toolchain;
+          };
+
+        in
+        naersk-lib.buildPackage (
+          buildPackageAttrs
+          // rec {
+            src = ./.;
+            strictDeps = true;
+            doCheck = false;
+
+            OPENSSL_STATIC = "1";
+            OPENSSL_LIB_DIR = "${pkgsCross.pkgsStatic.openssl.out}/lib";
+            OPENSSL_INCLUDE_DIR = "${pkgsCross.pkgsStatic.openssl.dev}/include";
+
+            # Required because ring crate is special. This also seems to have
+            # fixed some issues with the x86_64-windows cross-compile :shrug:
+            TARGET_CC = "${pkgsCross.stdenv.cc}/bin/${pkgsCross.stdenv.cc.targetPrefix}cc";
+
+            CARGO_BUILD_TARGET = rustTarget;
+            CARGO_BUILD_RUSTFLAGS = [
+              "-C"
+              "target-feature=+crt-static"
+
+              # https://github.com/rust-lang/cargo/issues/4133
+              "-C"
+              "linker=${TARGET_CC}"
+            ];
+          }
+        )
+      );
+    };
 }

rust-toolchain.toml

@@ -0,0 +1,4 @@
+[toolchain]
+channel = "stable"
+targets = [ "i686-unknown-linux-musl", "aarch64-unknown-linux-musl", "x86_64-unknown-linux-musl" ]
+profile = "minimal"