diff --git a/src/util/source_location.cpp b/src/util/source_location.cpp
new file mode 100644
index 0000000..105b144
--- /dev/null
+++ b/src/util/source_location.cpp
@@ -0,0 +1,46 @@
+// Copyright (c) 2021, The Monero Project
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without modification, are
+// permitted provided that the following conditions are met:
+//
+// 1. Redistributions of source code must retain the above copyright notice, this list of
+//    conditions and the following disclaimer.
+//
+// 2. Redistributions in binary form must reproduce the above copyright notice, this list
+//    of conditions and the following disclaimer in the documentation and/or other
+//    materials provided with the distribution.
+//
+// 3. Neither the name of the copyright holder nor the names of its contributors may be
+//    used to endorse or promote products derived from this software without specific
+//    prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
+// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
+// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
+// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#include <cstring>
+#include <ostream>
+#include "util/source_location.h"
+
+namespace lws
+{
+  std::ostream& operator<<(std::ostream& os, const source_location loc)
+  {
+    char const* const just_name = loc.file_name() ?
+      std::strrchr(loc.file_name(), '/') : nullptr;
+    if (loc.line())
+    {
+      os << (just_name ? just_name + 1 : loc.file_name()) << ':' << loc.line();
+    }
+    else
+      os << "(unknown source location)";
+    return os;
+  }
+}
diff --git a/src/util/source_location.h b/src/util/source_location.h
new file mode 100644
index 0000000..2c7d9f6
--- /dev/null
+++ b/src/util/source_location.h
@@ -0,0 +1,63 @@
+// Copyright (c) 2021, The Monero Project
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without modification, are
+// permitted provided that the following conditions are met:
+//
+// 1. Redistributions of source code must retain the above copyright notice, this list of
+//    conditions and the following disclaimer.
+//
+// 2. Redistributions in binary form must reproduce the above copyright notice, this list
+//    of conditions and the following disclaimer in the documentation and/or other
+//    materials provided with the distribution.
+//
+// 3. Neither the name of the copyright holder nor the names of its contributors may be
+//    used to endorse or promote products derived from this software without specific
+//    prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
+// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
+// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
+// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#pragma once
+#include <iosfwd>
+
+//! Expands to an object that tracks current source location
+#define MLWS_CURRENT_LOCATION ::lws::source_location{__FILE__, __LINE__}
+
+namespace lws
+{
+  //! Tracks source location in one object, with `std::ostream` output.
+  class source_location
+  {
+    // NOTE This is available in newer Boost versions
+    const char* file_;
+    int line_;
+
+  public:
+    constexpr source_location() noexcept
+      : file_(nullptr), line_(0)
+    {}
+
+    //! `file` must be in static memory
+    constexpr source_location(const char* file, int line) noexcept
+      : file_(file), line_(line)
+    {}
+
+    source_location(const source_location&) = default;
+    source_location& operator=(const source_location&) = default;
+
+    //! \return Possibly `nullptr`, otherwise full file path
+    const char* file_name() const noexcept { return file_; }
+    int line() const noexcept { return line_; }
+  };
+
+  //! Prints `loc.file_name() + ':' + loc.line()`
+  std::ostream& operator<<(std::ostream& os, source_location loc);
+}