diff --git a/libs/async/include/psemek/async/future.hpp b/libs/async/include/psemek/async/future.hpp
index 7a281526..d3b588c9 100644
--- a/libs/async/include/psemek/async/future.hpp
+++ b/libs/async/include/psemek/async/future.hpp
@@ -1,6 +1,7 @@
 #pragma once
 
 #include <psemek/util/function.hpp>
+#include <psemek/util/exception.hpp>
 
 #include <atomic>
 #include <mutex>
@@ -60,15 +61,19 @@ namespace psemek::async
 	}
 
 	struct empty_future_error
-		: std::exception
+		: util::exception
 	{
-		char const * what() const noexcept { return "future is empty"; }
+		empty_future_error(boost::stacktrace::stacktrace stacktrace = {})
+			: util::exception("Future is empty", std::move(stacktrace))
+		{}
 	};
 
 	struct canceled_task_error
-		: std::exception
+		: util::exception
 	{
-		char const * what() const noexcept { return "task canceled"; }
+		canceled_task_error(boost::stacktrace::stacktrace stacktrace = {})
+			: util::exception("Task canceled", std::move(stacktrace))
+		{}
 	};
 
 	struct auto_cancel_tag{};
@@ -177,15 +182,19 @@ namespace psemek::async
 	};
 
 	struct empty_promise_error
-		: std::exception
+		: util::exception
 	{
-		char const * what() const noexcept { return "promise is empty"; }
+		empty_promise_error(boost::stacktrace::stacktrace stacktrace = {})
+			: util::exception("Promise is empty", std::move(stacktrace))
+		{}
 	};
 
 	struct satisfied_promise_error
-		: std::exception
+		: util::exception
 	{
-		char const * what() const noexcept { return "promise already contains a value or exception"; }
+		satisfied_promise_error(boost::stacktrace::stacktrace stacktrace = {})
+			: util::exception("Promise already contains a value or exception", std::move(stacktrace))
+		{}
 	};
 
 	template <typename T>
diff --git a/libs/async/source/synchronous_executor.cpp b/libs/async/source/synchronous_executor.cpp
index 45eadb09..57179ce3 100644
--- a/libs/async/source/synchronous_executor.cpp
+++ b/libs/async/source/synchronous_executor.cpp
@@ -1,4 +1,5 @@
 #include <psemek/async/synchronous_executor.hpp>
+#include <psemek/util/exception.hpp>
 
 #include <stdexcept>
 
@@ -12,7 +13,7 @@ namespace psemek::async
 
 	void synchronous_executor::post_at(clock::time_point, task)
 	{
-		throw std::runtime_error("synchronous_executor doesn't support executor::post_at");
+		throw util::exception("Synchronous_executor doesn't support executor::post_at");
 	}
 
 	void synchronous_executor::stop()
diff --git a/libs/audio/source/recorder.cpp b/libs/audio/source/recorder.cpp
index fa9ef060..b60d5fc1 100644
--- a/libs/audio/source/recorder.cpp
+++ b/libs/audio/source/recorder.cpp
@@ -1,4 +1,5 @@
 #include <psemek/audio/recorder.hpp>
+#include <psemek/util/exception.hpp>
 
 #include <vector>
 
@@ -78,7 +79,7 @@ namespace psemek::audio
 	std::shared_ptr<track> record(stream_ptr stream)
 	{
 		if (!stream->length())
-			throw std::runtime_error("cannot record an infinite stream");
+			throw util::exception("Cannot record an infinite stream");
 		return record(stream, *stream->length());
 	}
 
diff --git a/libs/audio/source/track_raw.cpp b/libs/audio/source/track_raw.cpp
index eb27d525..713963e2 100644
--- a/libs/audio/source/track_raw.cpp
+++ b/libs/audio/source/track_raw.cpp
@@ -1,4 +1,5 @@
 #include <psemek/audio/track.hpp>
+#include <psemek/util/exception.hpp>
 
 #include <atomic>
 
@@ -82,14 +83,14 @@ namespace psemek::audio
 	track_ptr load_raw(util::span<float const> samples)
 	{
 		if ((samples.size() % 2) != 0)
-			throw std::runtime_error("bad sample count");
+			throw util::exception("Sample count must be even");
 		return std::make_shared<raw_track_impl>(std::make_shared<data_holder>(samples));
 	}
 
 	track_ptr load_raw(std::vector<float> samples)
 	{
 		if ((samples.size() % 2) != 0)
-			throw std::runtime_error("bad sample count");
+			throw util::exception("Sample count must be even");
 		return std::make_shared<raw_track_impl>(std::make_shared<data_holder>(std::move(samples)));
 	}
 
diff --git a/libs/audio/source/track_wav.cpp b/libs/audio/source/track_wav.cpp
index d3419cae..2177d597 100644
--- a/libs/audio/source/track_wav.cpp
+++ b/libs/audio/source/track_wav.cpp
@@ -3,6 +3,7 @@
 #include <psemek/audio/detail/resampler.hpp>
 #include <psemek/util/to_string.hpp>
 #include <psemek/util/at_scope_exit.hpp>
+#include <psemek/util/exception.hpp>
 
 #ifdef __GNUC__
 #pragma GCC diagnostic push
@@ -24,7 +25,7 @@ namespace psemek::audio
 		std::vector<float> convert_audio(std::vector<std::vector<float>> const & channels, int frequency)
 		{
 			if (channels.empty() || channels.size() > 2)
-				throw std::runtime_error(util::to_string("Can't convert audio with ", static_cast<int>(channels.size()), " channels"));
+				throw util::exception(util::to_string("Can't convert audio with ", static_cast<int>(channels.size()), " channels"));
 
 			std::vector<float> result(channels[0].size() * 2);
 			auto out = result.begin();
@@ -66,7 +67,7 @@ namespace psemek::audio
 		AudioFile<float> audio_file;
 		audio_file.shouldLogErrorsToConsole(false);
 		audio_file.onError = [](std::string const & error) {
-			throw std::runtime_error("failed to load WAV file: " + error);
+			throw util::exception("Failed to load WAV file: " + error);
 		};
 		audio_file.loadFromMemory(data_u8);
 
diff --git a/libs/fonts/source/bmfont.cpp b/libs/fonts/source/bmfont.cpp
index 113fcb07..cab715c7 100644
--- a/libs/fonts/source/bmfont.cpp
+++ b/libs/fonts/source/bmfont.cpp
@@ -1,9 +1,10 @@
 #include <psemek/fonts/bmfont.hpp>
 #include <psemek/util/to_string.hpp>
+#include <psemek/util/exception.hpp>
 
 #include <boost/preprocessor/stringize.hpp>
 
-#define RAPIDJSON_ASSERT(x) if (!(x)) throw ::std::runtime_error("Error parsing font description: " BOOST_PP_STRINGIZE(x));
+#define RAPIDJSON_ASSERT(x) if (!(x)) throw ::psemek::util::exception("Error parsing font description: " BOOST_PP_STRINGIZE(x));
 #define RAPIDJSON_NOEXCEPT_ASSERT(x)
 
 #include <rapidjson/document.h>
@@ -53,7 +54,7 @@ namespace psemek::fonts
 		document.ParseInsitu(description_str.data());
 
 		if (document.HasParseError())
-			throw std::runtime_error(util::to_string("Error msdf font description: ", to_string(document.GetParseError()), " at ", document.GetErrorOffset()));
+			throw util::exception(util::to_string("Error msdf font description: ", to_string(document.GetParseError()), " at ", document.GetErrorOffset()));
 
 		bmfont_data result;
 
diff --git a/libs/fonts/source/kerned_font.cpp b/libs/fonts/source/kerned_font.cpp
index 8ac1bab0..3c02d66a 100644
--- a/libs/fonts/source/kerned_font.cpp
+++ b/libs/fonts/source/kerned_font.cpp
@@ -1,6 +1,7 @@
 #include <psemek/fonts/kerned_font.hpp>
 
 #include <psemek/util/unicode.hpp>
+#include <psemek/util/exception.hpp>
 
 namespace psemek::fonts
 {
@@ -10,9 +11,9 @@ namespace psemek::fonts
 		, atlas_{std::move(atlas)}
 	{
 		if (!supports_character('?'))
-			throw std::runtime_error("Kerned font must support '?' character");
+			throw util::exception("Kerned font must support '?' character");
 		if (!supports_character(' '))
-			throw std::runtime_error("Kerned font must support ' ' character");
+			throw util::exception("Kerned font must support ' ' character");
 
 		std::vector<char32_t> chars;
 		for (auto const & g : data_.glyphs)
diff --git a/libs/fonts/source/monospace_font.cpp b/libs/fonts/source/monospace_font.cpp
index 6ffee890..6341042c 100644
--- a/libs/fonts/source/monospace_font.cpp
+++ b/libs/fonts/source/monospace_font.cpp
@@ -1,6 +1,7 @@
 #include <psemek/fonts/monospace_font.hpp>
 
 #include <psemek/util/unicode.hpp>
+#include <psemek/util/exception.hpp>
 
 namespace psemek::fonts
 {
@@ -13,10 +14,10 @@ namespace psemek::fonts
 		, texcoords_{std::move(texcoords)}
 	{
 		if (range_.end - range_.begin != texcoords_.size())
-			throw std::runtime_error("Wrong number of texture coordinates");
+			throw util::exception("Wrong number of texture coordinates");
 
 		if (!supports_character('?'))
-			throw std::runtime_error("Monospace font must support '?' character");
+			throw util::exception("Monospace font must support '?' character");
 	}
 
 	static geom::vector<float, 2> advance_dir(shape_options::direction_t direction)
diff --git a/libs/geom/include/psemek/geom/bezier.hpp b/libs/geom/include/psemek/geom/bezier.hpp
index 57f9a5f3..3c78feec 100644
--- a/libs/geom/include/psemek/geom/bezier.hpp
+++ b/libs/geom/include/psemek/geom/bezier.hpp
@@ -1,6 +1,7 @@
 #pragma once
 
 #include <psemek/geom/point.hpp>
+#include <psemek/util/exception.hpp>
 
 #include <vector>
 #include <stdexcept>
@@ -30,7 +31,7 @@ namespace psemek::geom
 			: points_(std::move(points))
 		{
 			if (points_.empty())
-				throw std::runtime_error("Points array should be non-empty");
+				throw util::exception("Points array should be non-empty");
 			temp_.resize(points_.size());
 		}
 
diff --git a/libs/geom/include/psemek/geom/detail/array.hpp b/libs/geom/include/psemek/geom/detail/array.hpp
index 3e451546..b7594549 100644
--- a/libs/geom/include/psemek/geom/detail/array.hpp
+++ b/libs/geom/include/psemek/geom/detail/array.hpp
@@ -1,17 +1,16 @@
 #pragma once
 
-#include <exception>
+#include <psemek/util/exception.hpp>
 
 namespace psemek::geom::detail
 {
 
 	struct empty_array_exception
-		: std::exception
+		: util::exception
 	{
-		char const * what() const noexcept
-		{
-			return "Attempt to index a zero vector";
-		}
+		empty_array_exception(boost::stacktrace::stacktrace stacktrace = {})
+			: util::exception("Indexing an empty array", std::move(stacktrace))
+		{}
 	};
 
 	template <typename T, std::size_t N>
diff --git a/libs/gfx/include/psemek/gfx/gltf_animation.hpp b/libs/gfx/include/psemek/gfx/gltf_animation.hpp
index 858f21ee..711c9e93 100644
--- a/libs/gfx/include/psemek/gfx/gltf_animation.hpp
+++ b/libs/gfx/include/psemek/gfx/gltf_animation.hpp
@@ -4,6 +4,7 @@
 #include <psemek/geom/scale.hpp>
 #include <psemek/geom/rotation.hpp>
 #include <psemek/geom/translation.hpp>
+#include <psemek/util/exception.hpp>
 
 #include <algorithm>
 
@@ -149,7 +150,7 @@ namespace psemek::gfx
 						);
 				}
 			default:
-				throw std::runtime_error("unsupported glTF animation interpolation type");
+				throw util::exception("Unknown glTF animation interpolation type");
 			}
 		}
 
diff --git a/libs/gfx/source/dither.cpp b/libs/gfx/source/dither.cpp
index 30681233..f57050ba 100644
--- a/libs/gfx/source/dither.cpp
+++ b/libs/gfx/source/dither.cpp
@@ -1,4 +1,5 @@
 #include <psemek/gfx/dither.hpp>
+#include <psemek/util/exception.hpp>
 
 namespace psemek::gfx
 {
@@ -25,7 +26,7 @@ namespace psemek::gfx
 	basic_pixmap<std::uint8_t> ordered_dither(std::size_t size)
 	{
 		if (size > 16)
-			throw std::runtime_error("8-bit dither map cannot be larger than 16x16");
+			throw util::exception("8-bit dither map cannot be larger than 16x16");
 
 		basic_pixmap<std::uint8_t> result({size, size});
 
diff --git a/libs/gfx/source/error.cpp b/libs/gfx/source/error.cpp
index fa9a7c34..dc45b59f 100644
--- a/libs/gfx/source/error.cpp
+++ b/libs/gfx/source/error.cpp
@@ -1,6 +1,7 @@
 #include <psemek/gfx/error.hpp>
 #include <psemek/gfx/gl.hpp>
 #include <psemek/util/to_string.hpp>
+#include <psemek/util/exception.hpp>
 
 #include <stdexcept>
 
@@ -31,8 +32,8 @@ namespace psemek::gfx
 
 		auto e = gl::GetError();
 
-		if (e != gl::GetError())
-			throw std::runtime_error(util::to_string(context, gl_error_str(e)));
+		if (e != gl::NO_ERROR)
+			throw util::exception(util::to_string(context, gl_error_str(e)));
 	}
 
 }
diff --git a/libs/gfx/source/framebuffer.cpp b/libs/gfx/source/framebuffer.cpp
index 93bf87f1..d3cb3f4c 100644
--- a/libs/gfx/source/framebuffer.cpp
+++ b/libs/gfx/source/framebuffer.cpp
@@ -1,6 +1,7 @@
 #include <psemek/gfx/framebuffer.hpp>
 
 #include <psemek/util/to_string.hpp>
+#include <psemek/util/exception.hpp>
 
 namespace psemek::gfx
 {
@@ -209,7 +210,7 @@ namespace psemek::gfx
 	void framebuffer::assert_complete(std::string_view name) const
 	{
 		if (auto s = status(); s != gl::FRAMEBUFFER_COMPLETE)
-			throw std::runtime_error(util::to_string("Framebuffer ", name, name.empty() ? "" : " ", "incomplete: ", framebuffer_status_string(s)));
+			throw util::exception(util::to_string("Framebuffer ", name, name.empty() ? "" : " ", "incomplete: ", framebuffer_status_string(s)));
 	}
 
 	framebuffer::framebuffer(std::nullptr_t)
diff --git a/libs/gfx/source/gltf_parser.cpp b/libs/gfx/source/gltf_parser.cpp
index 7c3f10a2..e31491a0 100644
--- a/libs/gfx/source/gltf_parser.cpp
+++ b/libs/gfx/source/gltf_parser.cpp
@@ -3,11 +3,12 @@
 #include <psemek/geom/rotation.hpp>
 #include <psemek/geom/translation.hpp>
 #include <psemek/util/to_string.hpp>
+#include <psemek/util/exception.hpp>
 #include <psemek/log/log.hpp>
 
 #include <boost/preprocessor/stringize.hpp>
 
-#define RAPIDJSON_ASSERT(x) if (!(x)) throw ::std::runtime_error("Error parsing glTF: " BOOST_PP_STRINGIZE(x));
+#define RAPIDJSON_ASSERT(x) if (!(x)) throw ::psemek::util::exception("Error parsing glTF: " BOOST_PP_STRINGIZE(x));
 #define RAPIDJSON_NOEXCEPT_ASSERT(x)
 
 #include <rapidjson/document.h>
@@ -65,7 +66,7 @@ namespace psemek::gfx
 				return gltf_asset::accessor::mat3;
 			if (type == "MAT4")
 				return gltf_asset::accessor::mat4;
-			throw std::runtime_error(util::to_string("Unknown accessor component type: ", type));
+			throw util::exception(util::to_string("Unknown accessor component type: ", type));
 		}
 
 		static std::unordered_set<std::string> supported_extensions =
@@ -126,14 +127,14 @@ namespace psemek::gfx
 		document.ParseInsitu(description_str.data());
 
 		if (document.HasParseError())
-			throw std::runtime_error(util::to_string("Error parsing glTF: ", to_string(document.GetParseError()), " at ", document.GetErrorOffset()));
+			throw util::exception(util::to_string("Error parsing glTF: ", to_string(document.GetParseError()), " at ", document.GetErrorOffset()));
 
 		gltf_asset result;
 
 		if (document.HasMember("extensionsRequired"))
 			for (auto const & extension : document["extensionsRequired"].GetArray())
 				if (!supported_extensions.contains(extension.GetString()))
-					throw std::runtime_error("glTF extension " + std::string(extension.GetString()) + " is not supported");
+					throw util::exception("glTF extension " + std::string(extension.GetString()) + " is not supported");
 
 		if (document.HasMember("nodes")) for (auto const & node : document["nodes"].GetArray())
 		{
@@ -323,7 +324,7 @@ namespace psemek::gfx
 				else if (path == "translation")
 					channel_target.path = gltf_asset::animation::channel::translation;
 				else
-					throw std::runtime_error("Unknown glTF animation target path: " + path);
+					throw util::exception("Unknown glTF animation target path: " + path);
 			}
 
 			for (auto const & sampler : animation["samplers"].GetArray())
@@ -341,7 +342,7 @@ namespace psemek::gfx
 				else if (interpolation == "CUBICSPLINE")
 					sampler_target.interpolation = geom::easing_type::cubic;
 				else
-					throw std::runtime_error("Unknown glTF animation interpolation type: " + interpolation);
+					throw util::exception("Unknown glTF animation interpolation type: " + interpolation);
 			}
 		}
 
@@ -401,7 +402,7 @@ namespace psemek::gfx
 					else if (type == "spot")
 						target.type = gltf_asset::light::spot;
 					else
-						throw std::runtime_error("unknown light type: " + type);
+						throw util::exception("Unknown light type: " + type);
 
 					if (light.HasMember("color"))
 					{
@@ -459,7 +460,7 @@ namespace psemek::gfx
 		case type_t::vec2: return 2;
 		case type_t::vec3: return 3;
 		case type_t::vec4: return 4;
-		default: throw std::runtime_error("unsupported attribute type");
+		default: throw util::exception("Unsupported attribute type");
 		}
 	}
 
diff --git a/libs/gfx/source/init.cpp b/libs/gfx/source/init.cpp
index b0a72cc1..2b10eeb6 100644
--- a/libs/gfx/source/init.cpp
+++ b/libs/gfx/source/init.cpp
@@ -1,6 +1,7 @@
 #include <psemek/gfx/init.hpp>
 #include <psemek/gfx/gl.hpp>
 #include <psemek/log/log.hpp>
+#include <psemek/util/exception.hpp>
 
 namespace psemek::gfx
 {
@@ -8,7 +9,7 @@ namespace psemek::gfx
 	void init()
 	{
 		if (!gl::sys::initialize())
-			throw std::runtime_error("Failed to load OpenGL functions");
+			throw util::exception("Failed to load OpenGL functions");
 
 		auto vendor = gl::GetString(gl::VENDOR);
 		auto renderer = gl::GetString(gl::RENDERER);
diff --git a/libs/gfx/source/mesh.cpp b/libs/gfx/source/mesh.cpp
index 19897e45..faafe4b0 100644
--- a/libs/gfx/source/mesh.cpp
+++ b/libs/gfx/source/mesh.cpp
@@ -2,6 +2,7 @@
 
 #include <psemek/util/to_string.hpp>
 #include <psemek/util/binary_stream.hpp>
+#include <psemek/util/exception.hpp>
 
 namespace psemek::gfx
 {
@@ -127,7 +128,7 @@ namespace psemek::gfx
 		case gl::UNSIGNED_BYTE: return 1;
 		case gl::UNSIGNED_SHORT: return 2;
 		case gl::UNSIGNED_INT: return 4;
-		default: throw std::runtime_error("Unknown undex type");
+		default: throw util::exception("Unknown undex type");
 		}
 	}
 
@@ -291,7 +292,7 @@ namespace psemek::gfx
 
 			auto pose_count = s.read<std::uint32_t>();
 			if (pose_count != result.bones.size())
-				throw std::runtime_error("Number of transforms in a pose must be equal to the number of bones");
+				throw util::exception("Number of transforms in a pose must be equal to the number of bones");
 			auto pose_ptr = s.read_ptr<bone_transform<float>>(pose_count);
 
 			std::string_view name(name_ptr, name_length);
@@ -310,32 +311,32 @@ namespace psemek::gfx
 			{
 			case SECTION_MESH:
 				if (had_section_mesh)
-					throw std::runtime_error("Section 'mesh' must not repeat");
+					throw util::exception("Section 'mesh' must not repeat");
 				parse_section_mesh();
 				had_section_mesh = true;
 				break;
 			case SECTION_BONES:
 				if (had_section_bones)
-					throw std::runtime_error("Section 'bones' must not repeat");
+					throw util::exception("Section 'bones' must not repeat");
 				if (!had_section_mesh)
-					throw std::runtime_error("Section 'bones' must come after section 'mesh'");
+					throw util::exception("Section 'bones' must come after section 'mesh'");
 				if ((vertex_format & WEIGHTS_MASK) == 0)
-					throw std::runtime_error("Section 'bones' requires weights in vertex format");
+					throw util::exception("Section 'bones' requires weights in vertex format");
 				parse_section_bones();
 				had_section_bones = true;
 				break;
 			case SECTION_POSE:
 				if (!had_section_bones)
-					throw std::runtime_error("Section 'pose' must come after section 'bones'");
+					throw util::exception("Section 'pose' must come after section 'bones'");
 				parse_section_pose();
 				break;
 			default:
-				throw std::runtime_error("Unknown section code " + util::to_string(section_type));
+				throw util::exception("Unknown section code " + util::to_string(section_type));
 			}
 		}
 
 		if (!had_section_mesh)
-			throw std::runtime_error("Section 'mesh' must be present");
+			throw util::exception("Section 'mesh' must be present");
 
 		return result;
 	}
diff --git a/libs/gfx/source/netpbm.cpp b/libs/gfx/source/netpbm.cpp
index 48a033f1..f8d401c4 100644
--- a/libs/gfx/source/netpbm.cpp
+++ b/libs/gfx/source/netpbm.cpp
@@ -1,4 +1,5 @@
 #include <psemek/gfx/pixmap.hpp>
+#include <psemek/util/exception.hpp>
 
 #include <iostream>
 #include <sstream>
@@ -11,7 +12,7 @@ namespace psemek::gfx
 	{
 		auto fail = [](std::string str)
 		{
-			throw std::runtime_error("Error loading PBM image: " + str);
+			throw util::exception("Error loading PBM image: " + str);
 		};
 
 		std::string line;
@@ -73,7 +74,7 @@ namespace psemek::gfx
 	{
 		auto fail = [](std::string str)
 		{
-			throw std::runtime_error("Error loading PGM image: " + str);
+			throw util::exception("Error loading PGM image: " + str);
 		};
 
 		std::string line;
@@ -134,7 +135,7 @@ namespace psemek::gfx
 	{
 		auto fail = [](std::string str)
 		{
-			throw std::runtime_error("Error loading PPM image: " + str);
+			throw util::exception("Error loading PPM image: " + str);
 		};
 
 		std::string line;
diff --git a/libs/gfx/source/obj_parser.cpp b/libs/gfx/source/obj_parser.cpp
index 87b8a7f2..7054946e 100644
--- a/libs/gfx/source/obj_parser.cpp
+++ b/libs/gfx/source/obj_parser.cpp
@@ -1,5 +1,6 @@
 #include <psemek/gfx/obj_parser.hpp>
 #include <psemek/util/to_string.hpp>
+#include <psemek/util/exception.hpp>
 
 #include <string>
 #include <sstream>
@@ -20,7 +21,7 @@ namespace psemek::gfx
 		std::size_t line_count = 0;
 
 		auto fail = [&](auto const & ... args){
-			throw std::runtime_error(util::to_string("Error parsing OBJ data, line ", line_count, ": ", args...));
+			throw util::exception(util::to_string("Error parsing OBJ data, line ", line_count, ": ", args...));
 		};
 
 		while (std::getline(is >> std::ws, line))
diff --git a/libs/gfx/source/painter.cpp b/libs/gfx/source/painter.cpp
index a43adec0..bb1420fe 100644
--- a/libs/gfx/source/painter.cpp
+++ b/libs/gfx/source/painter.cpp
@@ -5,6 +5,7 @@
 #include <psemek/gfx/resource/font_9x12_png.hpp>
 #include <psemek/geom/constants.hpp>
 #include <psemek/io/memory_stream.hpp>
+#include <psemek/util/enum.hpp>
 
 static const char vertex_source[] =
 R"(
@@ -290,7 +291,7 @@ namespace psemek::gfx
 			s = {9.f, 12.f};
 			break;
 		default:
-			throw std::runtime_error("Unknown font");
+			throw util::unknown_enum_value_exception(f);
 		}
 
 		s[0] *= str.size() * scale;
@@ -485,7 +486,7 @@ namespace psemek::gfx
 			pen[0] -= size[0];
 			break;
 		default:
-			throw std::runtime_error("Unknown x alignment");
+			throw util::unknown_enum_value_exception(opts.x);
 		}
 
 		switch (opts.y)
@@ -499,7 +500,7 @@ namespace psemek::gfx
 			pen[1] -= size[1];
 			break;
 		default:
-			throw std::runtime_error("Unknown y alignment");
+			throw util::unknown_enum_value_exception(opts.y);
 		}
 
 		geom::vector<float, 3> const sx = {9.f * opts.scale, 0.f, 0.f};
diff --git a/libs/gfx/source/png.cpp b/libs/gfx/source/png.cpp
index 979e1623..f3e77691 100644
--- a/libs/gfx/source/png.cpp
+++ b/libs/gfx/source/png.cpp
@@ -2,6 +2,7 @@
 
 #include <psemek/log/log.hpp>
 #include <psemek/util/at_scope_exit.hpp>
+#include <psemek/util/exception.hpp>
 
 #include <png.h>
 
@@ -16,7 +17,7 @@ namespace psemek::gfx
 		{
 			png_error_ptr error = [](png_structp, png_const_charp str)
 			{
-				throw std::runtime_error(str);
+				throw util::exception(str);
 			};
 
 			png_error_ptr warn = [](png_structp, png_const_charp str)
@@ -25,7 +26,7 @@ namespace psemek::gfx
 			};
 
 			auto png = png_create_read_struct(PNG_LIBPNG_VER_STRING, nullptr, error, warn);
-			if (!png) throw std::runtime_error("png_create_read_struct returned null");
+			if (!png) throw util::exception("png_create_read_struct returned null");
 
 			png_set_error_fn(png, nullptr, error, warn);
 
@@ -37,10 +38,10 @@ namespace psemek::gfx
 			});
 
 			info = png_create_info_struct(png);
-			if (!info) throw std::runtime_error("png_create_info_struct returned null");
+			if (!info) throw util::exception("png_create_info_struct returned null");
 
 			end_info = png_create_info_struct(png);
-			if (!end_info) throw std::runtime_error("png_create_info_struct returned null");
+			if (!end_info) throw util::exception("png_create_info_struct returned null");
 
 			png_rw_ptr read = [](png_structp png, png_bytep ptr, size_t count){
 				reinterpret_cast<io::istream *>(png_get_io_ptr(png))->read(reinterpret_cast<char *>(ptr), count);
@@ -58,7 +59,7 @@ namespace psemek::gfx
 				png_set_strip_16(png);
 
 			if (monochrome && color_type != PNG_COLOR_TYPE_GRAY)
-				throw std::runtime_error("invalid color type for monochrome PNG");
+				throw util::exception("Invalid color type for monochrome PNG");
 
 			if (color_type == PNG_COLOR_TYPE_PALETTE)
 				png_set_palette_to_rgb(png);
@@ -75,7 +76,7 @@ namespace psemek::gfx
 
 			auto const row_bytes = png_get_rowbytes(png, info);
 			if (row_bytes != width * sizeof(Pixel))
-				throw std::runtime_error("PNG row bytes mismatch");
+				throw util::exception("PNG row bytes mismatch");
 
 			for (std::uint32_t i = 0; i < height; ++i)
 				png_read_row(png, reinterpret_cast<png_bytep>(result.data() + i * width), nullptr);
@@ -87,7 +88,7 @@ namespace psemek::gfx
 		{
 			png_error_ptr error = [](png_structp, png_const_charp str)
 			{
-				throw std::runtime_error(str);
+				throw util::exception(str);
 			};
 
 			png_error_ptr warn = [](png_structp, png_const_charp str)
@@ -96,7 +97,7 @@ namespace psemek::gfx
 			};
 
 			auto png = png_create_write_struct(PNG_LIBPNG_VER_STRING, nullptr, error, warn);
-			if (!png) throw std::runtime_error("png_create_write_struct returned null");
+			if (!png) throw util::exception("png_create_write_struct returned null");
 
 			png_set_error_fn(png, nullptr, error, warn);
 
@@ -107,7 +108,7 @@ namespace psemek::gfx
 			});
 
 			info = png_create_info_struct(png);
-			if (!info) throw std::runtime_error("png_create_info_struct returned null");
+			if (!info) throw util::exception("png_create_info_struct returned null");
 
 			png_rw_ptr write = [](png_structp png, png_bytep ptr, size_t count){
 				reinterpret_cast<io::ostream *>(png_get_io_ptr(png))->write(reinterpret_cast<char const *>(ptr), count);
diff --git a/libs/gfx/source/program.cpp b/libs/gfx/source/program.cpp
index b4bd4feb..61dd387a 100644
--- a/libs/gfx/source/program.cpp
+++ b/libs/gfx/source/program.cpp
@@ -2,6 +2,7 @@
 
 #include <psemek/util/to_string.hpp>
 #include <psemek/util/at_scope_exit.hpp>
+#include <psemek/util/exception.hpp>
 
 #include <memory>
 #include <vector>
@@ -256,7 +257,7 @@ namespace psemek::gfx
 			gl::GetShaderiv(shader, gl::INFO_LOG_LENGTH, &log_len);
 			std::unique_ptr<char[]> log(new char [log_len]);
 			gl::GetShaderInfoLog(shader, log_len, nullptr, log.get());
-			throw std::runtime_error(util::to_string("Shader compilation failed: ", log.get(), "\nShader source: \n", annotated_source(source)));
+			throw util::exception(util::to_string("Shader compilation failed: ", log.get(), "\nShader source: \n", annotated_source(source)));
 		}
 	}
 
@@ -274,7 +275,7 @@ namespace psemek::gfx
 			gl::GetProgramiv(program, gl::INFO_LOG_LENGTH, &log_len);
 			std::unique_ptr<char[]> log(new char [log_len]);
 			gl::GetProgramInfoLog(program, log_len, nullptr, log.get());
-			throw std::runtime_error(util::to_string("Program link failed: ", log.get()));
+			throw util::exception(util::to_string("Program link failed: ", log.get()));
 		}
 
 		for (auto s : shaders)
diff --git a/libs/gfx/source/renderer/deferred.cpp b/libs/gfx/source/renderer/deferred.cpp
index 7716718f..27b1f4c8 100644
--- a/libs/gfx/source/renderer/deferred.cpp
+++ b/libs/gfx/source/renderer/deferred.cpp
@@ -27,6 +27,7 @@
 
 #include <psemek/util/to_string.hpp>
 #include <psemek/util/hash.hpp>
+#include <psemek/util/exception.hpp>
 
 #include <map>
 #include <unordered_map>
@@ -1079,13 +1080,13 @@ void main(){}
 			assert(o.mesh);
 
 			if (o.mat->lit && o.mat->transparent)
-				throw std::runtime_error("Materials that are both lit & transparent are not supported");
+				throw util::exception("Materials that are both lit & transparent are not supported");
 
 			if (o.mat->lit && o.mat->blooming)
-				throw std::runtime_error("Materials that are both lit & blooming are not supported");
+				throw util::exception("Materials that are both lit & blooming are not supported");
 
 			if (o.mat->casts_shadow && o.mat->transparent)
-				throw std::runtime_error("Transparent objects cannot cast shadow");
+				throw util::exception("Transparent objects cannot cast shadow");
 
 			auto c = o.bbox.center() - all_bbox.corner(0, 0, 0);
 
@@ -1567,9 +1568,9 @@ void main(){}
 			if (l.shadowed)
 			{
 				if (l.cascades == 0)
-					throw std::runtime_error("The number of shadow map cascades should be positive");
+					throw util::exception("The number of shadow map cascades should be positive");
 				if (l.cascades > 8)
-					throw std::runtime_error("More than 8 shadow map cascades are not supported");
+					throw util::exception("More than 8 shadow map cascades are not supported");
 
 				light_transform.resize(l.cascades);
 
diff --git a/libs/io/include/psemek/io/error.hpp b/libs/io/include/psemek/io/error.hpp
index b531b75f..780fda8b 100644
--- a/libs/io/include/psemek/io/error.hpp
+++ b/libs/io/include/psemek/io/error.hpp
@@ -1,36 +1,44 @@
 #pragma once
 
-#include <exception>
+#include <psemek/util/exception.hpp>
 
 namespace psemek::io
 {
 
 	struct null_stream
-		: std::exception
-	{};
+		: util::exception
+	{
+		using util::exception::exception;
+	};
 
 	struct null_istream
 		: null_stream
 	{
-		char const * what() const noexcept override;
+		null_istream(boost::stacktrace::stacktrace stacktrace = {});
 	};
 
 	struct null_ostream
 		: null_stream
 	{
-		char const * what() const noexcept override;
+		null_ostream(boost::stacktrace::stacktrace stacktrace = {});
+	};
+
+	struct stream_end
+		: util::exception
+	{
+		using util::exception::exception;
 	};
 
 	struct istream_end
-		: std::exception
+		: stream_end
 	{
-		char const * what() const noexcept override;
+		istream_end(boost::stacktrace::stacktrace stacktrace = {});
 	};
 
 	struct ostream_end
-		: std::exception
+		: stream_end
 	{
-		char const * what() const noexcept override;
+		ostream_end(boost::stacktrace::stacktrace stacktrace = {});
 	};
 
 }
diff --git a/libs/io/source/error.cpp b/libs/io/source/error.cpp
index 2690fb13..681fcce6 100644
--- a/libs/io/source/error.cpp
+++ b/libs/io/source/error.cpp
@@ -3,24 +3,20 @@
 namespace psemek::io
 {
 
-	char const * null_istream::what() const noexcept
-	{
-		return "Attempt to read from null input stream";
-	}
+	null_istream::null_istream(boost::stacktrace::stacktrace stacktrace)
+		: null_stream("Attempt to read from null input stream", std::move(stacktrace))
+	{}
 
-	char const * null_ostream::what() const noexcept
-	{
-		return "Attempt to write to null output stream";
-	}
+	null_ostream::null_ostream(boost::stacktrace::stacktrace stacktrace)
+		: null_stream("Attempt to write to null output stream", std::move(stacktrace))
+	{}
 
-	char const * istream_end::what() const noexcept
-	{
-		return "Unexpected input stream end";
-	}
+	istream_end::istream_end(boost::stacktrace::stacktrace stacktrace)
+		: stream_end("Unexpected input stream end", std::move(stacktrace))
+	{}
 
-	char const * ostream_end::what() const noexcept
-	{
-		return "Unexpected output stream end";
-	}
+	ostream_end::ostream_end(boost::stacktrace::stacktrace stacktrace)
+		: stream_end("Unexpected output stream end", std::move(stacktrace))
+	{}
 
 }
diff --git a/libs/io/source/file_stream.cpp b/libs/io/source/file_stream.cpp
index 56b3eb0e..0755c1ae 100644
--- a/libs/io/source/file_stream.cpp
+++ b/libs/io/source/file_stream.cpp
@@ -1,4 +1,5 @@
 #include <psemek/io/file_stream.hpp>
+#include <psemek/util/system_error.hpp>
 
 #include <cstring>
 #include <codecvt>
@@ -8,7 +9,7 @@ namespace psemek::io
 
 	static void throw_fopen [[noreturn]] (std::filesystem::path const & path)
 	{
-		throw std::system_error(std::error_code{errno, std::system_category()}, "Failed to open " + path.string());
+		throw util::system_error(std::error_code{errno, std::system_category()}, "Failed to open " + path.string());
 	}
 
 	static FILE * safe_fopen(std::filesystem::path const & path, const char * mode)
@@ -42,7 +43,7 @@ namespace psemek::io
 		{
 		case 0: return "wb";
 		case file_ostream::append: return "ab";
-		default: throw std::runtime_error("Unknown file_ostream open flags");
+		default: throw util::exception("Unknown file_ostream open flags");
 		}
 	}
 
diff --git a/libs/log/source/log.cpp b/libs/log/source/log.cpp
index 3ff85ec4..3a213494 100644
--- a/libs/log/source/log.cpp
+++ b/libs/log/source/log.cpp
@@ -1,5 +1,6 @@
 #include <psemek/log/log.hpp>
 #include <psemek/util/to_string.hpp>
+#include <psemek/util/exception.hpp>
 
 #include <chrono>
 #include <ctime>
@@ -153,7 +154,7 @@ namespace psemek::log
 
 			auto it = thread_names.find(id);
 			if (it != thread_names.end())
-				throw std::runtime_error("Thread \"" + name + "\" already registered!");
+				throw util::exception("Thread \"" + name + "\" already registered!");
 
 			thread_names[id] = name;
 		}
@@ -174,7 +175,7 @@ namespace psemek::log
 			{
 				std::ostringstream os;
 				os << "Thread " << id << " not found!";
-				throw std::runtime_error(os.str());
+				throw util::exception(os.str());
 			}
 
 			name = std::move(it->second);
diff --git a/libs/ml/include/psemek/ml/neural_net/activation.hpp b/libs/ml/include/psemek/ml/neural_net/activation.hpp
index e2ab6767..d5e7965b 100644
--- a/libs/ml/include/psemek/ml/neural_net/activation.hpp
+++ b/libs/ml/include/psemek/ml/neural_net/activation.hpp
@@ -1,5 +1,7 @@
 #pragma once
 
+#include <psemek/util/enum.hpp>
+
 #include <cmath>
 #include <algorithm>
 #include <exception>
@@ -10,21 +12,12 @@ namespace psemek::ml
 	// All activation functions are chosen in a way so that the derivative
 	//   can be expressed as a function of the activation function's value, i.e.
 	//   f'(x) = G(f(x)) for some G: R -> R
-	enum class activation_type
-	{
-		id,
-		sigmoid,
-		tanh,
-		relu,
-
-		count,
-	};
-
-	struct unknown_activation_type
-		: std::exception
-	{
-		char const * what() const noexcept override;
-	};
+	psemek_declare_enum(activation_type, std::uint8_t,
+		(id)
+		(sigmoid)
+		(tanh)
+		(relu)
+	)
 
 	template <typename T>
 	T activation(T x, activation_type type)
@@ -39,7 +32,7 @@ namespace psemek::ml
 		case activation_type::relu:
 			return std::max(T{0}, x);
 		default:
-			throw unknown_activation_type{};
+			throw util::unknown_enum_value_exception{type};
 		}
 	}
 
@@ -56,7 +49,7 @@ namespace psemek::ml
 		case activation_type::relu:
 			return value == T{0} ? T{0} : T{1};
 		default:
-			throw unknown_activation_type{};
+			throw util::unknown_enum_value_exception{type};
 		}
 	}
 
diff --git a/libs/ml/include/psemek/ml/neural_net/error.hpp b/libs/ml/include/psemek/ml/neural_net/error.hpp
index 9274e1fb..b1731822 100644
--- a/libs/ml/include/psemek/ml/neural_net/error.hpp
+++ b/libs/ml/include/psemek/ml/neural_net/error.hpp
@@ -1,39 +1,38 @@
 #pragma once
 
-#include <stdexcept>
-#include <cstddef>
+#include <psemek/util/exception.hpp>
 
 namespace psemek::ml
 {
 
 	struct neural_net_error
-		: std::runtime_error
+		: util::exception
 	{
-		using runtime_error::runtime_error;
+		using util::exception::exception;
 	};
 
 	struct empty_neural_net_error
 		: neural_net_error
 	{
-		empty_neural_net_error();
+		empty_neural_net_error(boost::stacktrace::stacktrace stacktrace = {});
 	};
 
 	struct wrong_activation_types_count_error
 		: neural_net_error
 	{
-		wrong_activation_types_count_error(std::size_t expected, std::size_t actual);
+		wrong_activation_types_count_error(std::size_t expected, std::size_t actual, boost::stacktrace::stacktrace stacktrace = {});
 	};
 
 	struct wrong_neural_net_input_size
 		: neural_net_error
 	{
-		wrong_neural_net_input_size(std::size_t expected, std::size_t actual);
+		wrong_neural_net_input_size(std::size_t expected, std::size_t actual, boost::stacktrace::stacktrace stacktrace = {});
 	};
 
 	struct wrong_neural_net_output_size
 		: neural_net_error
 	{
-		wrong_neural_net_output_size(std::size_t expected, std::size_t actual);
+		wrong_neural_net_output_size(std::size_t expected, std::size_t actual, boost::stacktrace::stacktrace stacktrace = {});
 	};
 
 }
diff --git a/libs/ml/source/neural_net/activation.cpp b/libs/ml/source/neural_net/activation.cpp
deleted file mode 100644
index 5fedabaf..00000000
--- a/libs/ml/source/neural_net/activation.cpp
+++ /dev/null
@@ -1,11 +0,0 @@
-#include <psemek/ml/neural_net/activation.hpp>
-
-namespace psemek::ml
-{
-
-	char const * unknown_activation_type::what() const noexcept
-	{
-		return "unknown activation type";
-	}
-
-}
diff --git a/libs/ml/source/neural_net/error.cpp b/libs/ml/source/neural_net/error.cpp
index 0393a951..b338de66 100644
--- a/libs/ml/source/neural_net/error.cpp
+++ b/libs/ml/source/neural_net/error.cpp
@@ -5,20 +5,20 @@
 namespace psemek::ml
 {
 
-	empty_neural_net_error::empty_neural_net_error()
-		: neural_net_error("neural net must have at least a single layer")
+	empty_neural_net_error::empty_neural_net_error(boost::stacktrace::stacktrace stacktrace)
+		: neural_net_error("Neural net must have at least a single layer", std::move(stacktrace))
 	{}
 
-	wrong_activation_types_count_error::wrong_activation_types_count_error(std::size_t expected, std::size_t actual)
-		: neural_net_error(util::to_string("wrong number of activation types: expected ", expected, ", got ", actual))
+	wrong_activation_types_count_error::wrong_activation_types_count_error(std::size_t expected, std::size_t actual, boost::stacktrace::stacktrace stacktrace)
+		: neural_net_error(util::to_string("Wrong number of activation types: expected ", expected, ", got ", actual), std::move(stacktrace))
 	{}
 
-	wrong_neural_net_input_size::wrong_neural_net_input_size(std::size_t expected, std::size_t actual)
-		: neural_net_error(util::to_string("wrong neural net input size: expected ", expected, ", got ", actual))
+	wrong_neural_net_input_size::wrong_neural_net_input_size(std::size_t expected, std::size_t actual, boost::stacktrace::stacktrace stacktrace)
+		: neural_net_error(util::to_string("Wrong neural net input size: expected ", expected, ", got ", actual), std::move(stacktrace))
 	{}
 
-	wrong_neural_net_output_size::wrong_neural_net_output_size(std::size_t expected, std::size_t actual)
-		: neural_net_error(util::to_string("wrong neural net output size: expected ", expected, ", got ", actual))
+	wrong_neural_net_output_size::wrong_neural_net_output_size(std::size_t expected, std::size_t actual, boost::stacktrace::stacktrace stacktrace)
+		: neural_net_error(util::to_string("Wrong neural net output size: expected ", expected, ", got ", actual), std::move(stacktrace))
 	{}
 
 }
diff --git a/libs/ml/tests/neural_net/gradient.cpp b/libs/ml/tests/neural_net/gradient.cpp
index a12e0c0f..3ff9c218 100644
--- a/libs/ml/tests/neural_net/gradient.cpp
+++ b/libs/ml/tests/neural_net/gradient.cpp
@@ -24,7 +24,7 @@ test_case(ml_neural__net_gradient)
 
 		std::vector<activation_type> activations(sizes.size() - 1);
 		for (auto & a : activations)
-			a = static_cast<activation_type>(uniform<std::size_t>(rng, 0, static_cast<std::size_t>(activation_type::count) - 1));
+			a = static_cast<activation_type>(uniform<std::size_t>(rng, 0, static_cast<std::size_t>(activation_type_values().size()) - 1));
 
 		neural_net<double> nn(std::move(sizes), std::move(activations));
 		randomize_normal(nn, rng);
@@ -71,7 +71,7 @@ test_case(ml_neural__net_arg__gradient)
 
 		std::vector<activation_type> activations(sizes.size() - 1);
 		for (auto & a : activations)
-			a = static_cast<activation_type>(uniform<std::size_t>(rng, 0, static_cast<std::size_t>(activation_type::count) - 1));
+			a = static_cast<activation_type>(uniform<std::size_t>(rng, 0, static_cast<std::size_t>(activation_type_values().size()) - 1));
 
 		neural_net<double> nn(std::move(sizes), std::move(activations));
 		randomize_normal(nn, rng);
diff --git a/libs/parser/include/psemek/parser/combinators.hpp b/libs/parser/include/psemek/parser/combinators.hpp
index 5dc7cacc..180e61c6 100644
--- a/libs/parser/include/psemek/parser/combinators.hpp
+++ b/libs/parser/include/psemek/parser/combinators.hpp
@@ -199,7 +199,7 @@ namespace psemek::parser
 				auto r = p.apply(buffer);
 				if (r.index() == 1) break;
 				if (buffer.it == pos)
-					throw grammar_error("infinite loop");
+					throw grammar_error("Infinite loop");
 				res.push_back(std::move(std::get<0>(r)));
 			}
 
@@ -265,7 +265,7 @@ namespace psemek::parser
 				if (res.index() == 1)
 					return accum;
 				if (pos == buffer.it)
-					throw grammar_error("infinite loop");
+					throw grammar_error("Infinite loop");
 
 				accum = f(accum, std::get<0>(res));
 			}
@@ -289,7 +289,7 @@ namespace psemek::parser
 				if (res.index() == 1)
 					return accum;
 				if (pos == buffer.it)
-					throw grammar_error("infinite loop");
+					throw grammar_error("Infinite loop");
 
 				accum = f(std::move(accum), std::move(std::get<0>(res)));
 			}
diff --git a/libs/parser/include/psemek/parser/parser.hpp b/libs/parser/include/psemek/parser/parser.hpp
index 749d3390..441af71f 100644
--- a/libs/parser/include/psemek/parser/parser.hpp
+++ b/libs/parser/include/psemek/parser/parser.hpp
@@ -8,37 +8,35 @@
 #include <memory>
 
 #include <psemek/util/to_string.hpp>
+#include <psemek/util/exception.hpp>
 
 namespace psemek::parser
 {
 
 	struct parse_error
-		: std::runtime_error
+		: util::exception
 	{
-		parse_error(std::string message, std::size_t line, std::size_t character)
-			: std::runtime_error(std::move(message))
+		parse_error(std::string message, std::size_t line, std::size_t character, boost::stacktrace::stacktrace stacktrace = {})
+			: util::exception(util::to_string(message, " at ", line, "#", character), std::move(stacktrace))
+			, message_{std::move(message)}
 			, line_{line}
 			, character_{character}
-			, what_{util::to_string(message, " at ", line, "#", character)}
 		{}
 
+		std::string const & message() const { return message_; }
 		std::size_t line() const { return line_; }
 		std::size_t character() const { return character_; }
 
-		const char * what() const noexcept { return what_.data(); }
-
 	private:
+		std::string message_;
 		std::size_t line_;
 		std::size_t character_;
-		std::string what_;
 	};
 
 	struct grammar_error
-		: std::runtime_error
+		: util::exception
 	{
-		grammar_error(std::string message)
-			: std::runtime_error(std::move(message))
-		{}
+		using util::exception::exception;
 	};
 
 	namespace detail
diff --git a/libs/random/include/psemek/random/uniform.hpp b/libs/random/include/psemek/random/uniform.hpp
index d125079e..ec277514 100644
--- a/libs/random/include/psemek/random/uniform.hpp
+++ b/libs/random/include/psemek/random/uniform.hpp
@@ -6,6 +6,8 @@
 #include <psemek/geom/constants.hpp>
 #include <psemek/geom/box.hpp>
 
+#include <psemek/util/exception.hpp>
+
 #include <type_traits>
 #include <stdexcept>
 
@@ -65,7 +67,7 @@ namespace psemek::random
 		using std::size;
 		using std::begin;
 		if (size(container) == 0)
-			throw std::runtime_error("cannot sample from empty container");
+			throw util::exception("Cannot sample from empty container");
 		return *std::next(begin(container), uniform<std::size_t>(rng, 0, size(container) - 1));
 	}
 
diff --git a/libs/rs/include/psemek/rs/registry.hpp b/libs/rs/include/psemek/rs/registry.hpp
index fb43390e..53360246 100644
--- a/libs/rs/include/psemek/rs/registry.hpp
+++ b/libs/rs/include/psemek/rs/registry.hpp
@@ -1,6 +1,7 @@
 #pragma once
 
 #include <psemek/rs/resource.hpp>
+#include <psemek/util/exception.hpp>
 
 #include <stdexcept>
 
@@ -8,9 +9,9 @@ namespace psemek::rs
 {
 
 	struct unknown_id_error
-		: std::runtime_error
+		: util::exception
 	{
-		unknown_id_error(rs::id id);
+		unknown_id_error(rs::id id, boost::stacktrace::stacktrace stacktrace = {});
 
 		rs::id id() const { return id_; }
 
@@ -19,9 +20,9 @@ namespace psemek::rs
 	};
 
 	struct unknown_name_error
-		: std::runtime_error
+		: util::exception
 	{
-		unknown_name_error(std::string_view name);
+		unknown_name_error(std::string_view name, boost::stacktrace::stacktrace stacktrace = {});
 
 		std::string_view name() const { return name_; }
 
diff --git a/libs/rs/source/registry.cpp b/libs/rs/source/registry.cpp
index ab67b4d9..e37e0a60 100644
--- a/libs/rs/source/registry.cpp
+++ b/libs/rs/source/registry.cpp
@@ -42,13 +42,13 @@ namespace psemek::rs
 
 	}
 
-	unknown_id_error::unknown_id_error(rs::id id)
-		: std::runtime_error(util::to_string("unknown resource id: ", id))
+	unknown_id_error::unknown_id_error(rs::id id, boost::stacktrace::stacktrace stacktrace)
+		: util::exception(util::to_string("unknown resource id: ", id), std::move(stacktrace))
 		, id_(id)
 	{}
 
-	unknown_name_error::unknown_name_error(std::string_view name)
-		: std::runtime_error(util::to_string("unknown resource name: ", name))
+	unknown_name_error::unknown_name_error(std::string_view name, boost::stacktrace::stacktrace stacktrace)
+		: util::exception(util::to_string("unknown resource name: ", name), std::move(stacktrace))
 	{}
 
 	resource const * find(id id)
diff --git a/libs/sdl2/source/init.cpp b/libs/sdl2/source/init.cpp
index 661f1664..8cfa47e1 100644
--- a/libs/sdl2/source/init.cpp
+++ b/libs/sdl2/source/init.cpp
@@ -1,5 +1,6 @@
 #include <psemek/sdl2/init.hpp>
 #include <psemek/log/log.hpp>
+#include <psemek/util/exception.hpp>
 
 #include <SDL2/SDL.h>
 
@@ -62,7 +63,7 @@ namespace psemek::sdl2
 
 	[[noreturn]] void fail(std::string const & message)
 	{
-		throw std::runtime_error(message + SDL_GetError());
+		throw util::exception(message + SDL_GetError());
 	}
 
 	std::shared_ptr<void> init(std::uint32_t subsystems)
diff --git a/libs/sir/include/psemek/sir/memory.hpp b/libs/sir/include/psemek/sir/memory.hpp
index 061d9ac4..8a50a749 100644
--- a/libs/sir/include/psemek/sir/memory.hpp
+++ b/libs/sir/include/psemek/sir/memory.hpp
@@ -4,6 +4,7 @@
 #include <psemek/sir/trivial.hpp>
 #include <psemek/sir/container.hpp>
 #include <psemek/io/memory_stream.hpp>
+#include <psemek/util/at.hpp>
 
 namespace psemek::sir
 {
@@ -27,7 +28,6 @@ namespace psemek::sir
 
 	private:
 		std::string_view data_;
-		std::size_t offset_;
 	};
 
 	static_assert(is_istream_v<memory_istream>);
@@ -93,7 +93,7 @@ namespace psemek::sir
 			T const & at(std::size_t i) const
 			{
 				if (i >= size())
-					throw std::out_of_range("psemek::sir::vector::at");
+					throw util::key_error(i);
 				return begin_[i];
 			}
 
@@ -263,7 +263,7 @@ namespace psemek::sir
 			{
 				auto p = find(key);
 				if (p == end_)
-					throw std::out_of_range("psemek::sir::map::at");
+					throw util::key_error(key);
 				return p->second;
 			}
 
diff --git a/libs/ui/include/psemek/ui/impl/component_factory_base.hpp b/libs/ui/include/psemek/ui/impl/component_factory_base.hpp
index e4aeefc1..1d6d24cc 100644
--- a/libs/ui/include/psemek/ui/impl/component_factory_base.hpp
+++ b/libs/ui/include/psemek/ui/impl/component_factory_base.hpp
@@ -7,6 +7,7 @@
 #include <psemek/util/to_string.hpp>
 #include <psemek/util/type_name.hpp>
 #include <psemek/util/function.hpp>
+#include <psemek/util/exception.hpp>
 
 #include <exception>
 #include <typeindex>
@@ -16,21 +17,20 @@ namespace psemek::ui::impl
 {
 
 	struct component_not_supported_exception
-		: std::exception
+		: util::exception
 	{
-		component_not_supported_exception(std::type_index type)
-			: type_(type)
-			, message_(util::to_string("UI component ", util::type_name(type_), " is not supported"))
+		component_not_supported_exception(std::type_index type, boost::stacktrace::stacktrace stacktrace = {})
+			: util::exception(util::to_string("UI component ", util::type_name(type_), " is not supported"), std::move(stacktrace))
+			, type_(type)
 		{}
 
-		const char * what() const noexcept override
+		std::type_index type() const
 		{
-			return message_.data();
+			return type_;
 		}
 
 	private:
 		std::type_index type_;
-		std::string message_;
 	};
 
 	struct component_factory_base
diff --git a/libs/util/include/psemek/util/assert.hpp b/libs/util/include/psemek/util/assert.hpp
index 5feb9977..e42723cc 100644
--- a/libs/util/include/psemek/util/assert.hpp
+++ b/libs/util/include/psemek/util/assert.hpp
@@ -1,9 +1,10 @@
 #pragma once
 
+#include <psemek/util/exception.hpp>
 #undef assert
 
 #ifdef PSEMEK_DEBUG
-#define assert(x) ((void)(!(x) && ::psemek::util::assert_handler(#x, __FILE__, __LINE__)))
+#define assert(x) ((void)(!(x) && ::psemek::util::assertion_handler("Assertion failed: " #x)))
 #else
 #define assert(x) ((void)(x))
 #endif
@@ -11,6 +12,9 @@
 namespace psemek::util
 {
 
-	[[noreturn]] bool assert_handler(char const * expression, char const * file, int line);
+	[[noreturn]] inline bool assertion_handler(char const * assertion, boost::stacktrace::stacktrace stacktrace = {})
+	{
+		 throw ::psemek::util::exception(assertion, std::move(stacktrace));
+	}
 
 }
diff --git a/libs/util/include/psemek/util/binary_stream.hpp b/libs/util/include/psemek/util/binary_stream.hpp
index 93e41bf4..249ca268 100644
--- a/libs/util/include/psemek/util/binary_stream.hpp
+++ b/libs/util/include/psemek/util/binary_stream.hpp
@@ -1,8 +1,8 @@
 #pragma once
 
-#include <string_view>
-#include <stdexcept>
+#include <psemek/util/exception.hpp>
 
+#include <string_view>
 #include <vector>
 
 namespace psemek::util
@@ -13,7 +13,7 @@ namespace psemek::util
 
 		inline void unexpected_end()
 		{
-			throw std::runtime_error("Unexpected binary stream end");
+			throw exception("Unexpected binary stream end");
 		}
 
 		template <typename T>
diff --git a/libs/util/include/psemek/util/ecs.hpp b/libs/util/include/psemek/util/ecs.hpp
index b364783e..3886a5d1 100644
--- a/libs/util/include/psemek/util/ecs.hpp
+++ b/libs/util/include/psemek/util/ecs.hpp
@@ -6,6 +6,7 @@
 #include <psemek/util/range.hpp>
 #include <psemek/util/hash.hpp>
 #include <psemek/util/hstring.hpp>
+#include <psemek/util/exception.hpp>
 
 #include <cstdint>
 #include <typeindex>
@@ -779,7 +780,7 @@ namespace psemek::util
 	{
 		auto p = species_[species.value]->get_species_component<Component>();
 		if (!p)
-			throw std::runtime_error(util::to_string("Component ", type_name<Component>(), " is not present in species ", species_[species.value]->name()));
+			throw util::exception(util::to_string("Component ", type_name<Component>(), " is not present in species ", species_[species.value]->name()));
 		return *p;
 	}
 
@@ -795,7 +796,7 @@ namespace psemek::util
 		auto u = ecs_detail::unpack(entity.value);
 		auto p = species_[u.species]->get_entity_component<Component>();
 		if (!p)
-			throw std::runtime_error(util::to_string("Component ", type_name<Component>(), " is not present in species ", species_[u.species]->name()));
+			throw util::exception(util::to_string("Component ", type_name<Component>(), " is not present in species ", species_[u.species]->name()));
 		return p[u.entity];
 	}
 
diff --git a/libs/util/include/psemek/util/enum.hpp b/libs/util/include/psemek/util/enum.hpp
index 76a4ae04..fba931d2 100644
--- a/libs/util/include/psemek/util/enum.hpp
+++ b/libs/util/include/psemek/util/enum.hpp
@@ -5,6 +5,7 @@
 
 #include <psemek/util/to_string.hpp>
 #include <psemek/util/type_name.hpp>
+#include <psemek/util/exception.hpp>
 
 #include <string_view>
 #include <stdexcept>
@@ -16,17 +17,17 @@ namespace psemek::util
 {
 
 	struct unknown_enum_value_exception_base
-		: std::runtime_error
+		: exception
 	{
-		using std::runtime_error::runtime_error;
+		using exception::exception;
 	};
 
 	template <typename Enum>
 	struct unknown_enum_value_exception
 		: unknown_enum_value_exception_base
 	{
-		unknown_enum_value_exception(Enum value)
-			: unknown_enum_value_exception_base(to_string("unknown ", type_name<Enum>(), " value: ", static_cast<std::underlying_type_t<Enum>>(value)))
+		unknown_enum_value_exception(Enum value, boost::stacktrace::stacktrace stacktrace = {})
+			: unknown_enum_value_exception_base(to_string("unknown ", type_name<Enum>(), " value: ", static_cast<std::underlying_type_t<Enum>>(value)), std::move(stacktrace))
 			, value_(value)
 		{}
 
diff --git a/libs/util/include/psemek/util/function.hpp b/libs/util/include/psemek/util/function.hpp
index d7679a2f..42d4cc6b 100644
--- a/libs/util/include/psemek/util/function.hpp
+++ b/libs/util/include/psemek/util/function.hpp
@@ -1,5 +1,7 @@
 #pragma once
 
+#include <psemek/util/exception.hpp>
+
 #include <type_traits>
 #include <memory>
 #include <functional>
@@ -7,6 +9,14 @@
 namespace psemek::util
 {
 
+	struct empty_function_error
+		: exception
+	{
+		empty_function_error(boost::stacktrace::stacktrace stacktrace = {})
+			: exception("Trying to call an empty function", std::move(stacktrace))
+		{}
+	};
+
 	template <typename Signature>
 	struct function;
 
@@ -149,7 +159,7 @@ namespace psemek::util
 	R function<R(Args...)>::operator()(Args1 && ... args) const
 	{
 		if (!vtable_)
-			throw std::bad_function_call();
+			throw empty_function_error{};
 
 		return vtable_->call(const_cast<void *>(static_cast<void const *>(&storage_)), std::forward<Args1>(args)...);
 	}
diff --git a/libs/util/include/psemek/util/heterogeneous_container.hpp b/libs/util/include/psemek/util/heterogeneous_container.hpp
index ba98de1b..166ccb75 100644
--- a/libs/util/include/psemek/util/heterogeneous_container.hpp
+++ b/libs/util/include/psemek/util/heterogeneous_container.hpp
@@ -1,6 +1,7 @@
 #pragma once
 
 #include <psemek/util/flat_list.hpp>
+#include <psemek/util/at.hpp>
 
 #include <tuple>
 #include <variant>
@@ -80,9 +81,10 @@ namespace psemek::util
 		template <typename F, typename T>
 		struct tuple_apply_at_impl<F, T, std::index_sequence<>>
 		{
-			static decltype(auto) apply(F && f, T & t, std::size_t)
+			static decltype(auto) apply(F && f, T & t, std::size_t i)
 			{
-				throw std::out_of_range("Bad tuple index");
+				throw key_error(i);
+				// For proper type deduction
 				return std::forward<F>(f)(std::get<0>(t));
 			}
 		};
@@ -105,21 +107,13 @@ namespace psemek::util
 		decltype(auto) tuple_apply_at(F && f, T & t, std::size_t i)
 		{
 			if (i >= std::tuple_size_v<T>)
-				throw std::out_of_range("Bad tuple index");
+				throw key_error(i);
 
 			return tuple_apply_at_impl<F, T, std::make_index_sequence<std::tuple_size_v<T>>>::apply(std::forward<F>(f), t, i);
 		}
 
 	}
 
-	struct bad_handle
-		: std::out_of_range
-	{
-		bad_handle()
-			: std::out_of_range("Bad handle")
-		{}
-	};
-
 	template <typename Handle, typename ... Types>
 	struct heterogeneous_container
 	{
@@ -230,7 +224,7 @@ namespace psemek::util
 	{
 		auto u = unpack_handle(h);
 		if (u.first >= types_count)
-			throw bad_handle{};
+			throw exception("Broken handle");
 		detail::tuple_apply_at([&u](auto & t) -> void {
 			t.erase(u.second);
 		}, storage_, u.first);
@@ -275,12 +269,12 @@ namespace psemek::util
 			if constexpr (std::is_same_v<std::decay_t<decltype(t[hh])>, T>)
 			{
 				if (i != j)
-					throw std::bad_any_cast{};
+					throw exception("Error in heterogeneous_container");
 				res = &t[hh];
 			}
 		}, storage_);
 		if (!res)
-			throw std::bad_any_cast{};
+			throw exception("Error in heterogeneous_container");
 
 		return *res;
 	}
@@ -298,12 +292,12 @@ namespace psemek::util
 			if constexpr (std::is_same_v<std::decay_t<decltype(t[hh])>, T>)
 			{
 				if (i != j)
-					throw std::bad_any_cast{};
+					throw exception("Error in heterogeneous_container");
 				res = &t[hh];
 			}
 		}, storage_);
 		if (!res)
-			throw std::bad_any_cast{};
+			throw exception("Error in heterogeneous_container");
 
 		return *res;
 	}
diff --git a/libs/util/include/psemek/util/not_implemented.hpp b/libs/util/include/psemek/util/not_implemented.hpp
index 45dd01e0..420e035d 100644
--- a/libs/util/include/psemek/util/not_implemented.hpp
+++ b/libs/util/include/psemek/util/not_implemented.hpp
@@ -1,14 +1,14 @@
 #pragma once
 
-#include <exception>
+#include <psemek/util/exception.hpp>
 
 namespace psemek::util
 {
 
 	struct not_implemented_error
-		: std::exception
+		: exception
 	{
-		char const * what() const noexcept override;
+		not_implemented_error(boost::stacktrace::stacktrace stacktrace = {});
 	};
 
 	[[noreturn]] void not_implemented();
diff --git a/libs/util/include/psemek/util/spatial_array.hpp b/libs/util/include/psemek/util/spatial_array.hpp
index 5bd94a2e..1bec02b1 100644
--- a/libs/util/include/psemek/util/spatial_array.hpp
+++ b/libs/util/include/psemek/util/spatial_array.hpp
@@ -1,6 +1,8 @@
 #pragma once
 
 #include <psemek/util/array.hpp>
+#include <psemek/util/exception.hpp>
+#include <psemek/util/to_string.hpp>
 
 #include <stdexcept>
 
@@ -112,7 +114,7 @@ namespace psemek::util
 		for (std::size_t i = 0; i < N; ++i)
 		{
 			if (ix[i] < origin_[i] || ix[i] >= origin_[i] + static_cast<Index>(size[i]))
-				throw std::runtime_error("element out of range");
+				throw exception(to_string("Spatial array index ", ix[i], "(#", i, ") is out of bounds [", origin_[i], origin_[i] + static_cast<Index>(size[i]), ")"));
 			ix[i] -= origin_[i];
 		}
 		return array_(ix);
diff --git a/libs/util/include/psemek/util/system_error.hpp b/libs/util/include/psemek/util/system_error.hpp
new file mode 100644
index 00000000..17f0f28a
--- /dev/null
+++ b/libs/util/include/psemek/util/system_error.hpp
@@ -0,0 +1,25 @@
+#pragma once
+
+#include <psemek/util/exception.hpp>
+
+namespace psemek::util
+{
+
+	struct system_error
+		: exception
+	{
+		system_error(std::error_code error_code, std::string message, boost::stacktrace::stacktrace stacktrace = {})
+			: exception(message + ": " + error_code.message(), std::move(stacktrace))
+			, error_code_(error_code)
+		{}
+
+		std::error_code error_code() const
+		{
+			return error_code_;
+		}
+
+	private:
+		std::error_code error_code_;
+	};
+
+}
diff --git a/libs/util/include/psemek/util/to_string.hpp b/libs/util/include/psemek/util/to_string.hpp
index 103f05fc..2e8a1161 100644
--- a/libs/util/include/psemek/util/to_string.hpp
+++ b/libs/util/include/psemek/util/to_string.hpp
@@ -1,5 +1,7 @@
 #pragma once
 
+#include <psemek/util/exception.hpp>
+
 #include <sstream>
 #include <stdexcept>
 
@@ -42,7 +44,7 @@ namespace psemek::util
 		T x;
 		iss >> x;
 		if (!iss)
-			throw std::invalid_argument("failed to parse from string");
+			throw exception("Failed to parse from string");
 		return x;
 	}
 
diff --git a/libs/util/include/psemek/util/unicode.hpp b/libs/util/include/psemek/util/unicode.hpp
index 2e7f807a..be388b55 100644
--- a/libs/util/include/psemek/util/unicode.hpp
+++ b/libs/util/include/psemek/util/unicode.hpp
@@ -1,8 +1,9 @@
 #pragma once
 
+#include <psemek/util/exception.hpp>
+
 #include <string>
 #include <iterator>
-#include <exception>
 
 namespace psemek::util
 {
@@ -70,14 +71,13 @@ namespace psemek::util
 	};
 
 	struct invalid_utf8
-		: std::exception
+		: exception
 	{
-		invalid_utf8(char const * data)
-			: data_{data}
+		invalid_utf8(char const * data, boost::stacktrace::stacktrace stacktrace = {})
+			: exception("Invalid UTF-8 string", std::move(stacktrace))
+			, data_{data}
 		{}
 
-		char const * what() const noexcept override;
-
 		char const * data() const { return data_; }
 
 	private:
diff --git a/libs/util/source/assert.cpp b/libs/util/source/assert.cpp
deleted file mode 100644
index 7950ab5a..00000000
--- a/libs/util/source/assert.cpp
+++ /dev/null
@@ -1,14 +0,0 @@
-#include <psemek/util/assert.hpp>
-#include <psemek/util/to_string.hpp>
-
-#include <stdexcept>
-
-namespace psemek::util
-{
-
-	[[noreturn]] bool assert_handler(char const * expression, char const * file, int line)
-	{
-		throw std::runtime_error(to_string(file, ":", line, " Assertion failed: ", expression));
-	}
-
-}
diff --git a/libs/util/source/executable_path.cpp b/libs/util/source/executable_path.cpp
index b4e92ff7..83415df8 100644
--- a/libs/util/source/executable_path.cpp
+++ b/libs/util/source/executable_path.cpp
@@ -1,5 +1,6 @@
 #include <psemek/util/executable_path.hpp>
 #include <psemek/util/to_string.hpp>
+#include <psemek/util/exception.hpp>
 
 #ifdef WIN32
 #include <libloaderapi.h>
@@ -23,13 +24,13 @@ namespace psemek::util
 			else if (error == ERROR_INSUFFICIENT_BUFFER)
 				result.resize(result.size() * 2);
 			else
-				throw std::runtime_error(util::to_string("failed to retrieve executable path: ", std::hex, error));
+				throw exception(util::to_string("failed to retrieve executable path: ", std::hex, error));
 		}
 		return std::filesystem::path(result);
 #elif defined __linux__
 		return std::filesystem::canonical("/proc/self/exe");
 #else
-		throw std::runtime_error("executable_path() is not implemented for this platform");
+		throw exception("executable_path() is not implemented for this platform");
 #endif
 	}
 
diff --git a/libs/util/source/function.cpp b/libs/util/source/function.cpp
deleted file mode 100644
index b2c513fb..00000000
--- a/libs/util/source/function.cpp
+++ /dev/null
@@ -1,18 +0,0 @@
-#include <psemek/util/function.hpp>
-
-#include <functional>
-
-namespace psemek::util
-{
-
-	namespace detail
-	{
-
-		void bad_function_call()
-		{
-			throw std::bad_function_call{};
-		}
-
-	}
-
-}
diff --git a/libs/util/source/not_implemented.cpp b/libs/util/source/not_implemented.cpp
index 70515579..5c3e6d83 100644
--- a/libs/util/source/not_implemented.cpp
+++ b/libs/util/source/not_implemented.cpp
@@ -5,10 +5,9 @@
 namespace psemek::util
 {
 
-	char const * not_implemented_error::what() const noexcept
-	{
-		return "not implemented";
-	}
+	not_implemented_error::not_implemented_error(boost::stacktrace::stacktrace stacktrace)
+		: exception("Not implemented", std::move(stacktrace))
+	{}
 
 	void not_implemented()
 	{
diff --git a/libs/util/source/unicode.cpp b/libs/util/source/unicode.cpp
index 38005dba..2b44ec43 100644
--- a/libs/util/source/unicode.cpp
+++ b/libs/util/source/unicode.cpp
@@ -110,9 +110,4 @@ namespace psemek::util
 			throw invalid_utf8(ptr);
 	}
 
-	char const * invalid_utf8::what() const noexcept
-	{
-		return "Invalid UTF-8 string";
-	}
-
 }
diff --git a/libs/util/tests/function.cpp b/libs/util/tests/function.cpp
index 688feaff..cc54656a 100644
--- a/libs/util/tests/function.cpp
+++ b/libs/util/tests/function.cpp
@@ -11,7 +11,7 @@ using namespace psemek::util;
 test_case(util_function_empty_call)
 {
 	function<void()> f;
-	expect_throw(f(), std::bad_function_call);
+	expect_throw(f(), empty_function_error);
 }
 
 using heavy = std::array<int, 256>;
diff --git a/libs/util/tests/heterogeneous_container.cpp b/libs/util/tests/heterogeneous_container.cpp
index 42f3983e..11b2255e 100644
--- a/libs/util/tests/heterogeneous_container.cpp
+++ b/libs/util/tests/heterogeneous_container.cpp
@@ -96,9 +96,9 @@ test_case(util_heterogeneous__container_get)
 	expect_equal_deref(std::get<2>(c.get(f0)), 3.14f);
 	expect_equal_deref(std::get<float *>(c.get(f0)), 3.14f);
 
-	expect_throw(c.get<float>(c0), std::bad_any_cast);
-	expect_throw(c.get<float>(c1), std::bad_any_cast);
-	expect_throw(c.get<char>(f0), std::bad_any_cast);
+	expect_throw(c.get<float>(c0), std::exception);
+	expect_throw(c.get<float>(c1), std::exception);
+	expect_throw(c.get<char>(f0), std::exception);
 }
 
 test_case(util_heterogeneous__container_visit)
diff --git a/tools/test/include/psemek/test/test.hpp b/tools/test/include/psemek/test/test.hpp
index 5d439d4f..0cbf3820 100644
--- a/tools/test/include/psemek/test/test.hpp
+++ b/tools/test/include/psemek/test/test.hpp
@@ -13,64 +13,70 @@
 
 // Have to put it before including to_string.hpp due to how unqualified lookup works,
 // see e.g. https://alexanderlobov.net/posts/2019-07-08-function-lookup-in-templates
-template <typename T>
-std::ostream & operator << (std::ostream & s, std::optional<T> const & o)
-{
-	if (o)
-		s << *o;
-	else
-		s << "(empty)";
-	return s;
-}
 
-template <typename T1, typename T2>
-std::ostream & operator << (std::ostream & s, std::pair<T1, T2> const & p)
+namespace std
 {
-	s << '(' << p.first << ", " << p.second << ')';
-	return s;
-}
 
-template <typename ... Ts>
-std::ostream & operator << (std::ostream & s, std::tuple<Ts...> const & t)
-{
-	s << '(';
-	[&]<std::size_t ... Is>(std::index_sequence<Is...>){
-		((s << (Is == 0 ? "" : ", ") << std::get<Is>(t)), ...);
-	}(std::make_index_sequence<sizeof...(Ts)>{});
-	s << ')';
-	return s;
-}
-
-template <typename T>
-std::ostream & operator << (std::ostream & s, std::vector<T> const & v)
-{
-	s << "[";
-	bool first = true;
-	for (auto const & x : v)
+	template <typename T>
+	ostream & operator << (ostream & s, optional<T> const & o)
 	{
-		if (!first)
-			s << ", ";
-		first = false;
-		s << x;
+		if (o)
+			s << *o;
+		else
+			s << "(empty)";
+		return s;
 	}
-	s << "]";
-	return s;
-}
 
-template <typename T>
-std::ostream & operator << (std::ostream & s, std::set<T> const & v)
-{
-	s << "{";
-	bool first = true;
-	for (auto const & x : v)
+	template <typename T1, typename T2>
+	ostream & operator << (ostream & s, pair<T1, T2> const & p)
 	{
-		if (!first)
-			s << ", ";
-		first = false;
-		s << x;
+		s << '(' << p.first << ", " << p.second << ')';
+		return s;
 	}
-	s << "}";
-	return s;
+
+	template <typename ... Ts>
+	ostream & operator << (ostream & s, tuple<Ts...> const & t)
+	{
+		s << '(';
+		[&]<size_t ... Is>(index_sequence<Is...>){
+			((s << (Is == 0 ? "" : ", ") << get<Is>(t)), ...);
+		}(make_index_sequence<sizeof...(Ts)>{});
+		s << ')';
+		return s;
+	}
+
+	template <typename T>
+	ostream & operator << (ostream & s, vector<T> const & v)
+	{
+		s << "[";
+		bool first = true;
+		for (auto const & x : v)
+		{
+			if (!first)
+				s << ", ";
+			first = false;
+			s << x;
+		}
+		s << "]";
+		return s;
+	}
+
+	template <typename T>
+	ostream & operator << (ostream & s, set<T> const & v)
+	{
+		s << "{";
+		bool first = true;
+		for (auto const & x : v)
+		{
+			if (!first)
+				s << ", ";
+			first = false;
+			s << x;
+		}
+		s << "}";
+		return s;
+	}
+
 }
 
 namespace psemek::util
@@ -81,16 +87,21 @@ namespace psemek::util
 
 }
 
-inline std::ostream & operator << (std::ostream & s, std::type_info const & type)
+namespace std
 {
-	s << psemek::util::type_name(type);
-	return s;
-}
 
-inline std::ostream & operator << (std::ostream & s, std::type_index const & type)
-{
-	s << psemek::util::type_name(type);
-	return s;
+	inline ostream & operator << (ostream & s, type_info const & type)
+	{
+		s << psemek::util::type_name(type);
+		return s;
+	}
+
+	inline ostream & operator << (ostream & s, type_index const & type)
+	{
+		s << psemek::util::type_name(type);
+		return s;
+	}
+
 }
 
 #include <psemek/util/to_string.hpp>