flake.nix,flake.lock: prepare rust environment

.gitignore

@@ -1 +1,2 @@
 result
+target

flake.lock

@@ -2,11 +2,11 @@
   "nodes": {
     "nixpkgs": {
       "locked": {
-        "lastModified": 1755082269,
-        "narHash": "sha256-Ix7ALeaxv9tW4uBKWeJnaKpYZtZiX4H4Q/MhEmj4XYA=",
+        "lastModified": 1766314097,
+        "narHash": "sha256-laJftWbghBehazn/zxVJ8NdENVgjccsWAdAqKXhErrM=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "d74de548348c46cf25cb1fcc4b74f38103a4590d",
+        "rev": "306ea70f9eb0fb4e040f8540e2deab32ed7e2055",
         "type": "github"
       },
       "original": {
@@ -17,7 +17,28 @@
     },
     "root": {
       "inputs": {
-        "nixpkgs": "nixpkgs"
+        "nixpkgs": "nixpkgs",
+        "rust-overlay": "rust-overlay"
+      }
+    },
+    "rust-overlay": {
+      "inputs": {
+        "nixpkgs": [
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1766371695,
+        "narHash": "sha256-W7CX9vy7H2Jj3E8NI4djHyF8iHSxKpb2c/7uNQ/vGFU=",
+        "owner": "oxalica",
+        "repo": "rust-overlay",
+        "rev": "d81285ba8199b00dc31847258cae3c655b605e8c",
+        "type": "github"
+      },
+      "original": {
+        "owner": "oxalica",
+        "repo": "rust-overlay",
+        "type": "github"
       }
     }
   },

flake.nix

@@ -1,7 +1,12 @@
 {
-  inputs.nixpkgs.url = "nixpkgs/nixpkgs-unstable";
+  inputs = {
+    nixpkgs.url = "nixpkgs/nixpkgs-unstable";
 
-  outputs = { self, nixpkgs }: let
+    rust-overlay.url = "github:oxalica/rust-overlay";
+    rust-overlay.inputs.nixpkgs.follows = "nixpkgs";
+  };
+
+  outputs = { self, nixpkgs, rust-overlay }: let
     inherit (nixpkgs) lib;
 
     systems = [
@@ -12,16 +17,33 @@
       "armv7l-linux"
     ];
 
-    forAllSystems = f: lib.genAttrs systems (system: f system nixpkgs.legacyPackages.${system});
+    forAllSystems = f: nixpkgs.lib.genAttrs systems (system: let
+      pkgs = import nixpkgs {
+        inherit system;
+        overlays = [
+          (import rust-overlay)
+        ];
+      };
+
+      rust-bin = rust-overlay.lib.mkRustBin { } pkgs.buildPackages;
+      toolchain = rust-bin.stable.latest.default.override {
+        extensions = [ "rust-src" ];
+      };
+    in f system pkgs toolchain);
   in {
-    devShells = forAllSystems (system: pkgs: {
+    devShells = forAllSystems (system: pkgs: toolchain: {
       default = pkgs.mkShell {
         packages = with pkgs; [
+          toolchain
+          cargo-edit
+
           ruff
           (python3.withPackages (ppkgs: with ppkgs; [
             psycopg2-binary
           ]))
         ];
+
+        env.RUST_SRC_PATH = "${toolchain}/lib/rustlib/src/rust/library";
       };
     });
 
@@ -31,7 +53,7 @@
 
     nixosModules.default = ./module.nix;
 
-    packages = forAllSystems (system: pkgs: {
+    packages = forAllSystems (system: pkgs: _: {
       default = self.packages.${system}.mclog2psql;
       mclog2psql = pkgs.writers.writePython3Bin "mclog2psql" {
         libraries = [ pkgs.python3Packages.psycopg2 ];