proper error handling

flake.nix

@@ -9,7 +9,6 @@
 
   outputs =
     {
-      self,
       nixpkgs,
       naersk,
       fenix,
@@ -72,14 +71,11 @@
         pkgs = import nixpkgs { inherit system; };
         rust = fenix.packages.${system}.stable;
       in
-      with pkgs;
       {
-        devShells.default = mkShell {
+        devShells.default = pkgs.mkShell {
           buildInputs = [
-            mosquitto
             rust.toolchain
-            rust-analyzer
-            sea-orm-cli
+            pkgs.rust-analyzer
           ];
         };
       }