diff --git a/libaegisub/common/cajun/reader.cpp b/libaegisub/common/cajun/reader.cpp
index 5db3c1060..f03566904 100644
--- a/libaegisub/common/cajun/reader.cpp
+++ b/libaegisub/common/cajun/reader.cpp
@@ -8,9 +8,9 @@ Author: Terry Caton
 
 #include "libaegisub/cajun/reader.h"
 
+#include <boost/interprocess/streams/bufferstream.hpp>
 #include <cassert>
 #include <set>
-#include <sstream>
 
 /*
 
@@ -320,7 +320,7 @@ UnknownElement Reader::ParseNumber(Reader::TokenStream& tokenStream) {
 	std::string const& sValue = MatchExpectedToken(Token::TOKEN_NUMBER, tokenStream);
 
 	// First try to parse it as an int
-	std::istringstream iStr(sValue);
+	boost::interprocess::ibufferstream iStr(sValue.data(), sValue.size());
 	int64_t iValue;
 	iStr >> iValue;
 
diff --git a/libaegisub/common/json.cpp b/libaegisub/common/json.cpp
index 5834faad8..00343b27c 100644
--- a/libaegisub/common/json.cpp
+++ b/libaegisub/common/json.cpp
@@ -20,22 +20,20 @@
 
 #include "libaegisub/json.h"
 
-#include <fstream>
-#include <memory>
-#include <sstream>
-
 #include "libaegisub/fs.h"
 #include "libaegisub/io.h"
 #include "libaegisub/log.h"
 #include "libaegisub/util.h"
 
+#include <boost/interprocess/streams/bufferstream.hpp>
+
 namespace agi {
 	namespace json_util {
 
-json::UnknownElement parse(std::unique_ptr<std::istream> stream) {
+json::UnknownElement parse(std::istream &stream) {
 	try {
 		json::UnknownElement root;
-		json::Reader::Read(root, *stream);
+		json::Reader::Read(root, stream);
 		return root;
 	} catch (json::Reader::ParseException& e) {
 		LOG_E("json/parse") << "json::ParseException: " << e.what() << ", Line/offset: " << e.m_locTokenBegin.m_nLine + 1 << '/' << e.m_locTokenBegin.m_nLineOffset + 1;
@@ -47,24 +45,27 @@ json::UnknownElement parse(std::unique_ptr<std::istream> stream) {
 }
 
 json::UnknownElement file(agi::fs::path const& file) {
-	return parse(io::Open(file));
+	return parse(*io::Open(file));
 }
 
 json::UnknownElement file(agi::fs::path const& file, const std::string &default_config) {
 	try {
-		return parse(io::Open(file));
+		return parse(*io::Open(file));
 	}
 	catch (fs::FileNotFound const&) {
 		// Not an error
-		return parse(util::make_unique<std::istringstream>(default_config));
+		boost::interprocess::ibufferstream stream(default_config.data(), default_config.size());
+		return parse(stream);
 	}
 	catch (json::Exception&) {
 		// Already logged in parse
-		return parse(util::make_unique<std::istringstream>(default_config));
+		boost::interprocess::ibufferstream stream(default_config.data(), default_config.size());
+		return parse(stream);
 	}
 	catch (agi::Exception& e) {
 		LOG_E("json/file") << "Unexpected error when reading config file " << file << ": " << e.GetMessage();
-		return parse(util::make_unique<std::istringstream>(default_config));
+		boost::interprocess::ibufferstream stream(default_config.data(), default_config.size());
+		return parse(stream);
 	}
 }
 
diff --git a/libaegisub/common/log.cpp b/libaegisub/common/log.cpp
index 46b981f12..f78b32fd3 100644
--- a/libaegisub/common/log.cpp
+++ b/libaegisub/common/log.cpp
@@ -93,9 +93,8 @@ Message::Message(const char *section, Severity severity, const char *file, const
 }
 
 Message::~Message() {
-	sm.message = std::string(msg.str(), (std::string::size_type)msg.pcount());
+	sm.message = std::string(buffer, (std::string::size_type)msg.tellp());
 	agi::log::log->Log(sm);
-	msg.freeze(false);
 }
 
 JsonEmitter::JsonEmitter(fs::path const& directory)
diff --git a/libaegisub/common/option.cpp b/libaegisub/common/option.cpp
index 3d3a3c811..87693a665 100644
--- a/libaegisub/common/option.cpp
+++ b/libaegisub/common/option.cpp
@@ -31,11 +31,11 @@
 
 #include "option_visit.h"
 
+#include <boost/interprocess/streams/bufferstream.hpp>
 #include <boost/range/adaptor/map.hpp>
 #include <cassert>
 #include <fstream>
 #include <memory>
-#include <sstream>
 
 namespace {
 	/// @brief Write an option to a json object
@@ -72,7 +72,7 @@ Options::Options(agi::fs::path const& file, const std::string& default_config, c
 , setting(setting)
 {
 	LOG_D("agi/options") << "New Options object";
-	std::istringstream stream(default_config);
+	boost::interprocess::ibufferstream stream(default_config.data(), default_config.size());
 	LoadConfig(stream);
 }
 
diff --git a/libaegisub/common/vfr.cpp b/libaegisub/common/vfr.cpp
index 15dadf99a..4ee0be669 100644
--- a/libaegisub/common/vfr.cpp
+++ b/libaegisub/common/vfr.cpp
@@ -20,7 +20,14 @@
 
 #include "libaegisub/vfr.h"
 
+#include "libaegisub/charset.h"
+#include "libaegisub/io.h"
+#include "libaegisub/line_iterator.h"
+#include "libaegisub/scoped_ptr.h"
+
 #include <algorithm>
+#include <boost/interprocess/streams/bufferstream.hpp>
+#include <boost/range/algorithm.hpp>
 #include <cmath>
 #include <fstream>
 #include <functional>
@@ -28,13 +35,6 @@
 #include <list>
 #include <numeric>
 
-#include "libaegisub/charset.h"
-#include "libaegisub/io.h"
-#include "libaegisub/line_iterator.h"
-#include "libaegisub/scoped_ptr.h"
-
-#include <boost/range/algorithm.hpp>
-
 namespace {
 
 static const int64_t default_denominator = 1000000000;
@@ -73,7 +73,7 @@ struct TimecodeRange {
 TimecodeRange v1_parse_line(std::string const& str) {
 	if (str.empty() || str[0] == '#') return TimecodeRange();
 
-	std::istringstream ss(str);
+	boost::interprocess::ibufferstream ss(str.data(), str.size());
 	TimecodeRange range;
 	char comma1 = 0, comma2 = 0;
 	ss >> range.start >> comma1 >> range.end >> comma2 >> range.fps;
diff --git a/libaegisub/include/libaegisub/json.h b/libaegisub/include/libaegisub/json.h
index 0fb67ecfe..9b799780c 100644
--- a/libaegisub/include/libaegisub/json.h
+++ b/libaegisub/include/libaegisub/json.h
@@ -28,7 +28,7 @@ namespace agi {
 /// Parse a JSON stream.
 /// @param stream JSON stream to parse
 /// @return json::UnknownElement
-json::UnknownElement parse(std::unique_ptr<std::istream> stream);
+json::UnknownElement parse(std::istream &stream);
 
 /// Parse a JSON file.
 /// @param file Path JSON to file
diff --git a/libaegisub/include/libaegisub/line_iterator.h b/libaegisub/include/libaegisub/line_iterator.h
index e34f4b8bd..27e91c570 100644
--- a/libaegisub/include/libaegisub/line_iterator.h
+++ b/libaegisub/include/libaegisub/line_iterator.h
@@ -20,9 +20,9 @@
 
 #include <iterator>
 #include <memory>
-#include <sstream>
 
 #include <cstdint>
+#include <boost/interprocess/streams/bufferstream.hpp>
 #include <boost/algorithm/string/case_conv.hpp>
 
 #include <libaegisub/charset_conv.h>
@@ -205,7 +205,7 @@ inline void line_iterator<std::string>::next() {
 
 template<class OutputType>
 inline bool line_iterator<OutputType>::convert(std::string &str) {
-	std::istringstream ss(str);
+	boost::interprocess::ibufferstream ss(str.data(), str.size());
 	ss >> value;
 	return !ss.fail();
 }
diff --git a/libaegisub/include/libaegisub/log.h b/libaegisub/include/libaegisub/log.h
index da965f458..f2c6b75f7 100644
--- a/libaegisub/include/libaegisub/log.h
+++ b/libaegisub/include/libaegisub/log.h
@@ -21,18 +21,11 @@
 
 #include <ctime>
 #include <boost/circular_buffer.hpp>
+#include <boost/interprocess/streams/bufferstream.hpp>
 #include <iosfwd>
 #include <memory>
 #include <vector>
 
-#ifdef __DEPRECATED // Dodge GCC warnings
-# undef __DEPRECATED
-# include <strstream>
-# define __DEPRECATED
-#else
-# include <strstream>
-#endif
-
 // These macros below aren't a perm solution, it will depend on how annoying they are through
 // actual usage, and also depends on msvc support.
 #define LOG_SINK(section, severity) agi::log::Message(section, severity, __FILE__, __FUNCTION__, __LINE__).stream()
@@ -137,7 +130,7 @@ public:
 
 /// Generates a message and submits it to the log sink.
 class Message {
-	std::ostrstream msg;
+	boost::interprocess::obufferstream msg;
 	SinkMessage sm;
 	char buffer[2048];
 
diff --git a/libaegisub/lagi_pre.h b/libaegisub/lagi_pre.h
index 044eedac1..a206b3b8d 100644
--- a/libaegisub/lagi_pre.h
+++ b/libaegisub/lagi_pre.h
@@ -48,7 +48,6 @@
 #include <memory>
 #include <numeric>
 #include <set>
-#include <sstream>
 #include <stdexcept>
 #include <string>
 #include <tuple>
@@ -64,11 +63,4 @@
 #define BOOST_NO_SCOPED_ENUMS
 #include <boost/filesystem.hpp>
 #undef BOOST_NO_SCOPED_ENUMS
-
-#ifdef __DEPRECATED // Dodge GCC warnings
-# undef __DEPRECATED
-# include <strstream>
-# define __DEPRECATED
-#else
-# include <strstream>
-#endif
+#include <boost/interprocess/streams/bufferstream.hpp>
diff --git a/src/main.cpp b/src/main.cpp
index 3437f1d7b..5e7e924e2 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -67,8 +67,8 @@
 
 #include <boost/filesystem/fstream.hpp>
 #include <boost/format.hpp>
+#include <boost/interprocess/streams/bufferstream.hpp>
 #include <boost/locale.hpp>
-#include <sstream>
 
 #include <wx/clipbrd.h>
 #include <wx/config.h>
@@ -181,7 +181,7 @@ bool AegisubApp::OnInit() {
 	try {
 		if (!config::opt)
 			config::opt = new agi::Options(config::path->Decode("?user/config.json"), GET_DEFAULT_CONFIG(default_config));
-		std::istringstream stream(GET_DEFAULT_CONFIG(default_config_platform));
+		boost::interprocess::ibufferstream stream((const char *)default_config, sizeof(default_config));
 		config::opt->ConfigNext(stream);
 	} catch (agi::Exception& e) {
 		LOG_E("config/init") << "Caught exception: " << e.GetName() << " -> " << e.GetMessage();
diff --git a/src/toolbar.cpp b/src/toolbar.cpp
index b57ceebd7..208f8b14a 100644
--- a/src/toolbar.cpp
+++ b/src/toolbar.cpp
@@ -36,7 +36,7 @@
 #include <libaegisub/util.h>
 
 #include <boost/algorithm/string/join.hpp>
-#include <sstream>
+#include <boost/interprocess/streams/bufferstream.hpp>
 #include <vector>
 
 #include <wx/frame.h>
@@ -45,8 +45,10 @@
 namespace {
 	json::Object const& get_root() {
 		static json::Object root;
-		if (root.empty())
-			root = agi::json_util::parse(agi::util::make_unique<std::istringstream>(GET_DEFAULT_CONFIG(default_toolbar)));
+		if (root.empty()) {
+			boost::interprocess::ibufferstream stream((const char *)default_toolbar, sizeof(default_toolbar));
+			root = agi::json_util::parse(stream);
+		}
 		return root;
 	}