diff --git a/nixos/modules/module-list.nix b/nixos/modules/module-list.nix
index 599ea640f67c..ab7c63117ff3 100644
--- a/nixos/modules/module-list.nix
+++ b/nixos/modules/module-list.nix
@@ -664,6 +664,7 @@
   ./services/mail/mailcatcher.nix
   ./services/mail/mailhog.nix
   ./services/mail/mailman.nix
+  ./services/mail/mailpit.nix
   ./services/mail/mlmmj.nix
   ./services/mail/nullmailer.nix
   ./services/mail/offlineimap.nix
diff --git a/nixos/modules/services/mail/mailpit.nix b/nixos/modules/services/mail/mailpit.nix
new file mode 100644
index 000000000000..c60e30faf0d8
--- /dev/null
+++ b/nixos/modules/services/mail/mailpit.nix
@@ -0,0 +1,103 @@
+{
+  config,
+  lib,
+  pkgs,
+  ...
+}:
+
+let
+  cfg = config.services.mailpit;
+  inherit (lib)
+    cli
+    concatStringsSep
+    const
+    filterAttrs
+    getExe
+    mkEnableOption
+    mkIf
+    mkOption
+    types
+    ;
+
+  isNonNull = v: v != null;
+  cliFlags = concatStringsSep " " (
+    cli.toGNUCommandLine { } (filterAttrs (const isNonNull) cfg.settings)
+  );
+in
+{
+  options.services.mailpit = {
+    enable = mkEnableOption "mailpit";
+
+    settings = mkOption {
+      default = { };
+      type = types.submodule {
+        freeformType = types.attrsOf (
+          types.oneOf [
+            types.str
+            types.int
+            types.bool
+          ]
+        );
+        options = {
+          database = mkOption {
+            type = types.nullOr types.str;
+            default = null;
+            example = "mailpit.db";
+            description = ''
+              Specify the local database filename to store persistent data.
+              If `null`, a temporary file will be created that will be removed when the application stops.
+              It's recommended to specify a relative path. The database will be written into the service's
+              state directory then.
+            '';
+          };
+          max = mkOption {
+            type = types.ints.unsigned;
+            default = 500;
+            description = ''
+              Maximum number of emails to keep. If the number is exceeded, old emails
+              will be deleted.
+
+              Set to `0` to never prune old emails.
+            '';
+          };
+          listen = mkOption {
+            default = "0.0.0.0:8025";
+            type = types.str;
+            description = ''
+              HTTP bind interface and port for UI.
+            '';
+          };
+          smtp = mkOption {
+            default = "0.0.0.0:1025";
+            type = types.str;
+            description = ''
+              SMTP bind interface and port.
+            '';
+          };
+        };
+      };
+      description = ''
+        Attribute-set of all flags passed to mailpit. See
+        [upstream docs](https://mailpit.axllent.org/docs/configuration/runtime-options/)
+        for all available options.
+      '';
+    };
+  };
+
+  config = mkIf cfg.enable {
+    systemd.services.mailpit = {
+      wantedBy = [ "multi-user.target" ];
+      after = [ "network-online.target" ];
+      wants = [ "network-online.target" ];
+      serviceConfig = {
+        DynamicUser = true;
+        StateDirectory = "mailpit";
+        WorkingDirectory = "%S/mailpit";
+        ExecStart = "${getExe pkgs.mailpit} ${cliFlags}";
+        Restart = "on-failure";
+      };
+    };
+  };
+
+  meta.maintainers = lib.teams.flyingcircus.members;
+}
diff --git a/nixos/tests/all-tests.nix b/nixos/tests/all-tests.nix
index 424ccf4d9a44..fe3336c1e9fb 100644
--- a/nixos/tests/all-tests.nix
+++ b/nixos/tests/all-tests.nix
@@ -552,6 +552,7 @@ in {
   magnetico = handleTest ./magnetico.nix {};
   mailcatcher = handleTest ./mailcatcher.nix {};
   mailhog = handleTest ./mailhog.nix {};
+  mailpit = handleTest ./mailpit.nix {};
   mailman = handleTest ./mailman.nix {};
   man = handleTest ./man.nix {};
   mariadb-galera = handleTest ./mysql/mariadb-galera.nix {};
diff --git a/nixos/tests/mailpit.nix b/nixos/tests/mailpit.nix
new file mode 100644
index 000000000000..79beb227534b
--- /dev/null
+++ b/nixos/tests/mailpit.nix
@@ -0,0 +1,35 @@
+import ./make-test-python.nix (
+  { lib, ... }:
+  {
+    name = "mailpit";
+    meta.maintainers = lib.teams.flyingcircus.members;
+
+    nodes.machine =
+      { pkgs, ... }:
+      {
+        services.mailpit.enable = true;
+
+        environment.systemPackages = with pkgs; [ swaks ];
+      };
+
+    testScript = ''
+      start_all()
+
+      from json import loads
+
+      machine.wait_for_unit("mailpit.service")
+      machine.wait_for_open_port(1025)
+      machine.wait_for_open_port(8025)
+      machine.succeed(
+          'echo "this is the body of the email" | swaks --to root@example.org --body - --server localhost:1025'
+      )
+
+      received = loads(machine.succeed("curl http://localhost:8025/api/v1/messages"))
+      assert received['total'] == 1
+      message = received["messages"][0]
+      assert len(message['To']) == 1
+      assert message['To'][0]['Address'] == 'root@example.org'
+      assert "this is the body of the email" in message['Snippet']
+    '';
+  }
+)
diff --git a/pkgs/servers/mail/mailpit/default.nix b/pkgs/servers/mail/mailpit/default.nix
index da62efd9f7a2..fd8f01674d80 100644
--- a/pkgs/servers/mail/mailpit/default.nix
+++ b/pkgs/servers/mail/mailpit/default.nix
@@ -10,6 +10,7 @@
   fetchNpmDeps,
   testers,
   mailpit,
+  nixosTests,
 }:
 
 let
@@ -78,9 +79,12 @@ buildGoModule {
     cp -r ${ui} server/ui/dist
   '';
 
-  passthru.tests.version = testers.testVersion {
-    package = mailpit;
-    command = "mailpit version";
+  passthru.tests = {
+    inherit (nixosTests) mailpit;
+    version = testers.testVersion {
+      package = mailpit;
+      command = "mailpit version";
+    };
   };
 
   passthru.updateScript = {