diff --git a/src/filesystem_sdl.cpp b/src/filesystem_sdl.cpp
index f3780a54c4d..5337cfd3a9d 100644
--- a/src/filesystem_sdl.cpp
+++ b/src/filesystem_sdl.cpp
@@ -18,6 +18,7 @@
 #include "log.hpp"
 
 #include <algorithm>
+#include <cassert>
 
 static lg::log_domain log_filesystem("filesystem");
 #define ERR_FS LOG_STREAM(err, log_filesystem)
diff --git a/src/gui/auxiliary/iterator/policy_order.hpp b/src/gui/auxiliary/iterator/policy_order.hpp
index 72765714105..5f264d285f6 100644
--- a/src/gui/auxiliary/iterator/policy_order.hpp
+++ b/src/gui/auxiliary/iterator/policy_order.hpp
@@ -20,6 +20,7 @@
 #include "gui/widgets/widget.hpp"
 
 #include <iostream>
+#include <cassert>
 
 namespace gui2
 {
diff --git a/src/gui/dialogs/outro.cpp b/src/gui/dialogs/outro.cpp
index b2cf620acd3..b8e3f65e2e1 100644
--- a/src/gui/dialogs/outro.cpp
+++ b/src/gui/dialogs/outro.cpp
@@ -25,6 +25,8 @@
 #include "gui/widgets/settings.hpp"
 #include "gui/widgets/window.hpp"
 
+#include <cmath>
+
 namespace gui2
 {
 namespace dialogs
diff --git a/src/gui/widgets/generator.cpp b/src/gui/widgets/generator.cpp
index 5a5c308e18f..5744ff8f01f 100644
--- a/src/gui/widgets/generator.cpp
+++ b/src/gui/widgets/generator.cpp
@@ -20,6 +20,7 @@
 #include "wml_exception.hpp"
 
 #include <numeric>
+#include <cmath>
 
 namespace gui2
 {
diff --git a/src/log.cpp b/src/log.cpp
index ca8ef9aaeee..a8fa302ac68 100644
--- a/src/log.cpp
+++ b/src/log.cpp
@@ -47,7 +47,6 @@ static bool timestamp = true;
 static bool precise_timestamp = false;
 static std::mutex log_mutex;
 
-static boost::posix_time::time_facet facet("%Y%m%d %H:%M:%S%F ");
 static std::ostream *output_stream = nullptr;
 
 static std::ostream& output()
@@ -198,14 +197,15 @@ std::string get_timespan(const std::time_t& t) {
 	return sout.str();
 }
 
-static void print_precise_timestamp(std::ostream & out) noexcept
+static void print_precise_timestamp(std::ostream& out) noexcept
 {
 	try {
-		facet.put(
-			std::ostreambuf_iterator<char>(out),
-			out,
-			' ',
-			boost::posix_time::microsec_clock::local_time());
+		int64_t micros = std::chrono::duration_cast<std::chrono::microseconds>(std::chrono::high_resolution_clock::now().time_since_epoch()).count();
+		std::time_t seconds = micros/1'000'000;
+		int fractional = micros-(seconds*1'000'000);
+		char c = out.fill('0');
+		out << std::put_time(std::localtime(&seconds), "%Y%m%d %H:%M:%S") << "." << std::setw(6) << fractional;
+		out.fill(c);
 	} catch(...) {}
 }
 
@@ -269,7 +269,7 @@ void scope_logger::do_log_entry(const std::string& str) noexcept
 {
 	str_ = str;
 	try {
-		ticks_ = boost::posix_time::microsec_clock::local_time();
+		ticks_ = std::chrono::duration_cast<std::chrono::microseconds>(std::chrono::high_resolution_clock::now().time_since_epoch()).count();
 	} catch(...) {}
 	debug()(domain_, false, true) | formatter() << "{ BEGIN: " << str_ << "\n";
 	++indent;
@@ -279,7 +279,7 @@ void scope_logger::do_log_exit() noexcept
 {
 	long ticks = 0;
 	try {
-		ticks = (boost::posix_time::microsec_clock::local_time() - ticks_).total_milliseconds();
+		ticks = std::chrono::duration_cast<std::chrono::microseconds>(std::chrono::high_resolution_clock::now().time_since_epoch()).count() - ticks_;
 	} catch(...) {}
 	--indent;
 	auto output = debug()(domain_, false, true);
diff --git a/src/log.hpp b/src/log.hpp
index 02e53939f3f..e8cebe30b12 100644
--- a/src/log.hpp
+++ b/src/log.hpp
@@ -56,12 +56,10 @@
 #include <sstream> // as above. iostream (actually, iosfwd) declares stringstream as an incomplete type, but does not define it
 #include <string>
 #include <utility>
+#include <ctime>
 
-#include <boost/date_time/posix_time/posix_time_types.hpp>
 #include "formatter.hpp"
 
-using boost::posix_time::ptime;
-
 namespace lg {
 
 /**
@@ -167,7 +165,7 @@ log_domain& general();
 
 class scope_logger
 {
-	ptime ticks_;
+	int64_t ticks_;
 	const log_domain& domain_;
 	std::string str_;
 public: