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diff --git a/libs/archive/src/instrument.h b/libs/archive/src/instrument.h
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+/*
+Mod Organizer archive handling
+
+Copyright (C) 2020 MO2 Team. All rights reserved.
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 3 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+*/
+
+#ifndef ARCHIVE_INSTRUMENT_H
+#define ARCHIVE_INSTRUMENT_H
+
+#include <chrono>
+#include <format>
+
+namespace ArchiveTimers
+{
+
+/**
+ * If INSTRUMENT_ARCHIVE is not defined, we define a Timer() class that is empty and
+ * does nothing, and thus should be optimized out by the compiler.
+ */
+#ifdef INSTRUMENT_ARCHIVE
+
+/**
+ * Small class that can be used to instrument portion of code using a guard.
+ *
+ */
+class Timer
+{
+public:
+  using clock_t = std::chrono::system_clock;
+
+  struct TimerGuard
+  {
+
+    TimerGuard(TimerGuard const&)            = delete;
+    TimerGuard(TimerGuard&&)                 = delete;
+    TimerGuard& operator=(TimerGuard const&) = delete;
+    TimerGuard& operator=(TimerGuard&&)      = delete;
+
+    ~TimerGuard()
+    {
+      m_Timer.ncalls++;
+      m_Timer.time += clock_t::now() - m_Start;
+    }
+
+  private:
+    TimerGuard(Timer& timer) : m_Timer{timer}, m_Start{clock_t::now()} {}
+
+    Timer& m_Timer;
+    clock_t::time_point m_Start;
+
+    friend class Timer;
+  };
+
+  /**
+   *
+   */
+  Timer() = default;
+
+  /**
+   * @brief Instrument a portion of code.
+   *
+   * Instrumenting is done by calling `instrument()` and storing the result in a local
+   * variable. The scope of the local guard variable is the scope of the
+   * instrumentation.
+   *
+   * @return a guard to instrument the code.
+   */
+  TimerGuard instrument() { return {*this}; }
+
+  std::wstring toString(std::wstring const& name) const
+  {
+    auto ms = [](auto&& t) {
+      return std::chrono::duration<double, std::milli>(t);
+    };
+    return std::format(
+        L"Instrument '{}': {} calls, total of {}ms, {:.3f}ms per call on average.",
+        name, ncalls, ms(time).count(), ms(time).count() / ncalls);
+  }
+
+private:
+  std::size_t ncalls{0};
+  clock_t::duration time{0};
+};
+
+#else
+
+struct Timer
+{
+  // This is the only method needed:
+  Timer& instrument() { return *this; }
+};
+
+#endif
+
+}  // namespace ArchiveTimers
+
+#endif