Stripped tser.hpp down to the essentials so I can study it. No base64 encoding, less than comparison (wtf is that for), and I may even remove the 'json' output.

tests/config.cpp

@@ -75,7 +75,9 @@ struct MyData
   std::string tiles;
 
   template<class Archive>
-    serialize(Archive &ar) { ar(x, y, z, tiles); }
+    void serialize(Archive &ar) {
+      ar(x, y, z, tiles);
+    }
 };
 
 
@@ -104,3 +106,40 @@ TEST_CASE("test using serialization", "[config]") {
     REQUIRE(m3.tiles == "\u2849█Ω♣");
   }
 }
+
+#include <optional>
+#include <iostream>
+#include "tser.hpp"
+
+enum class Item : char {
+  RADAR = 'R',
+  TRAP = 'T',
+  ORE = 'O'
+};
+
+struct Pixel {
+  int x = 0;
+  int y = 0;
+
+  DEFINE_SERIALIZABLE(Pixel, x, y);
+};
+
+struct Robot {
+  Pixel point;
+  std::optional<Item> item;
+
+  DEFINE_SERIALIZABLE(Robot, point, item);
+};
+
+TEST_CASE("test using tser for serialization", "[config]") {
+  auto robot = Robot{ Pixel{3,4}, Item::RADAR};
+  std::cout << robot << '\n';
+  std::cout << Robot() << '\n';
+
+  tser::BinaryArchive archive;
+  archive.save(robot);
+  std::string_view archive_view = archive.get_buffer();
+
+  auto loadedRobot = tser::load<Robot>(archive_view);
+  REQUIRE(loadedRobot == robot);
+}