[nix] expose a nixos module

flake.nix

@@ -20,7 +20,7 @@
           pkgs.haskell.lib.doJailbreak (pkg.overrideAttrs (_: { meta = { }; }));
 
         # DON'T FORGET TO PUT YOUR PACKAGE NAME HERE, REMOVING `throw`
-        packageName = "quptes-api";
+        packageName = "quotes-api";
       in {
         packages.${packageName} = haskellPackages.callCabal2nix packageName self
           rec {
@@ -30,10 +30,53 @@
         packages.default = self.packages.${system}.${packageName};
         defaultPackage = self.packages.${system}.default;
 
+        nixosModules = {
+          quotes-api = { config, lib, pkgs, ... }:
+
+            with lib;
+            let cfg = config.services.quotes-api;
+            in {
+              options.services.quotes-api = {
+                enable = mkEnableOption "Enables quotes api service";
+
+                port = mkOption rec {
+                  type = types.int;
+                  default = 8123;
+                  example = default;
+                  description = "bind port";
+                };
+
+                dbpath = mkOption rec {
+                  type = types.string;
+                  default = "/tmp/sqlite.db";
+                  example = default;
+                  description = "Path to sqlite database";
+                };
+              };
+
+              config = mkIf cfg.enable {
+                systemd.services."quotes-api" = {
+                  wantedBy = [ "multi-user.target" ];
+
+                  serviceConfig =
+                    let pkg = self.packages.${pkgs.system}.default;
+                    in {
+                      Restart = "on-failure";
+                      ExecStart = "${pkg}/bin/quotes-api --port ${
+                          builtins.toString cfg.port
+                        } --dbpath ${cfg.dbpath}";
+                    };
+                };
+
+              };
+            };
+        };
+
+        nixosModule = self.nixosModules.${system}.quotes-api;
+
         devShells.default = pkgs.mkShell {
           buildInputs = with pkgs; [
             haskellPackages.haskell-language-server # you must build it with your ghc to work
-            haskellPackages.hoogle
             ghcid
             hlint
             ghc