Add sqlx

Signed-off-by: Nikolaos Karaolidis <nick@karaolidis.com>

flake.nix

@@ -0,0 +1,52 @@
+{
+  inputs = {
+    nixpkgs = {
+      type = "github";
+      owner = "karaolidis";
+      repo = "nixpkgs";
+      ref = "integration";
+    };
+
+    flake-utils = {
+      type = "github";
+      owner = "numtide";
+      repo = "flake-utils";
+      ref = "main";
+    };
+
+    treefmt-nix = {
+      type = "github";
+      owner = "numtide";
+      repo = "treefmt-nix";
+      ref = "main";
+
+      inputs.nixpkgs.follows = "nixpkgs";
+    };
+  };
+
+  outputs =
+    { self, nixpkgs, ... }@inputs:
+    inputs.flake-utils.lib.eachDefaultSystem (
+      system:
+      let
+        pkgs = nixpkgs.legacyPackages.${system};
+        treefmt = inputs.treefmt-nix.lib.evalModule pkgs ./treefmt.nix;
+      in
+      {
+        devShells.default = pkgs.mkShell {
+          packages = with pkgs; [
+            cargo
+            rustc
+            rustfmt
+            clippy
+            cargo-udeps
+            cargo-outdated
+            sqlx-cli
+          ];
+        };
+
+        formatter = treefmt.config.build.wrapper;
+        checks.formatting = treefmt.config.build.check self;
+      }
+    );
+}