diff --git a/src/Format.h b/src/Format.h
index b29749bde..85b63c7f1 100644
--- a/src/Format.h
+++ b/src/Format.h
@@ -9,30 +9,6 @@ namespace format
 {
 	const static char hex[] = "0123456789ABCDEF";
 
-	template <typename T> ByteString NumberToByteString(T number)
-	{
-		ByteString::Stream ss;
-		ss << number;
-		return ss.str();
-	}
-
-	template <typename T> String NumberToString(T number)
-	{
-		return String::Build(number);
-	}
-
-	template <typename T> T ByteStringToNumber(const ByteString & text)
-	{
-		ByteString::Stream ss(text);
-		T number;
-		return (ss >> number)?number:0;
-	}
-
-	template <typename T> T StringToNumber(const String & text)
-	{
-		return text.ToNumber<T>(true);
-	}
-
 	ByteString URLEncode(ByteString value);
 	ByteString UnixtimeToDate(time_t unixtime, ByteString dateFomat = "%d %b %Y");
 	ByteString UnixtimeToDateMini(time_t unixtime);
diff --git a/src/PowderToySDL.cpp b/src/PowderToySDL.cpp
index 4fd0bb32e..e65f485b6 100644
--- a/src/PowderToySDL.cpp
+++ b/src/PowderToySDL.cpp
@@ -1009,7 +1009,7 @@ int main(int argc, char * argv[])
 
 	if(arguments["scale"].length())
 	{
-		tempScale = format::ByteStringToNumber<int>(arguments["scale"]);
+		tempScale = arguments["scale"].ToNumber<int>();
 		Client::Ref().SetPref("Scale", tempScale);
 	}
 
@@ -1181,9 +1181,7 @@ int main(int argc, char * argv[])
 #ifdef DEBUG
 				std::cout << "Got Ptsave: id: " << saveIdPart << std::endl;
 #endif
-				int saveId = format::ByteStringToNumber<int>(saveIdPart);
-				if (!saveId)
-					throw std::runtime_error("Invalid Save ID");
+				int saveId = saveIdPart.ToNumber<int>();
 
 				SaveInfo * newSave = Client::Ref().GetSave(saveId, 0);
 				if (!newSave)
diff --git a/src/client/Client.cpp b/src/client/Client.cpp
index 4741c896a..a43741dc1 100644
--- a/src/client/Client.cpp
+++ b/src/client/Client.cpp
@@ -150,7 +150,7 @@ void Client::Initialise(ByteString proxyString)
 
 	if (authUser.UserID)
 	{
-		ByteString idTempString = format::NumberToByteString<int>(authUser.UserID);
+		ByteString idTempString = ByteString::Build(authUser.UserID);
 		char *id = new char[idTempString.length() + 1];
 		std::strcpy (id, idTempString.c_str());
 		char *session = new char[authUser.SessionID.length() + 1];
@@ -378,12 +378,11 @@ bool Client::DoInstallation()
 "NoDisplay=true\n"
 "Categories=Game;Simulation\n"
 "Icon=powdertoy.png\n";
-	ByteString::Stream protocolfiledata;
-	protocolfiledata << protocolfiledata_tmp << "Exec=" << filename << " ptsave %u\nPath=" << pathname << "\n";
+	ByteString protocolfiledata = ByteString::Build(protocolfiledata_tmp, "Exec=", filename, " ptsave %u\nPath=", pathname, "\n");
 	f = fopen("powdertoy-tpt-ptsave.desktop", "wb");
 	if (!f)
 		return 0;
-	fwrite(protocolfiledata.str().c_str(), 1, strlen(protocolfiledata.str().c_str()), f);
+	fwrite(protocolfiledata.c_str(), 1, protocolfiledata.size(), f);
 	fclose(f);
 	success = system("xdg-desktop-menu install powdertoy-tpt-ptsave.desktop");
 
@@ -396,12 +395,11 @@ bool Client::DoInstallation()
 "NoDisplay=true\n"
 "Categories=Game;Simulation\n"
 "Icon=powdertoy.png\n";
-	ByteString::Stream desktopopenfiledata;
-	desktopopenfiledata << desktopopenfiledata_tmp << "Exec=" << filename << " open %f\nPath=" << pathname << "\n";
+	ByteString desktopopenfiledata = ByteString::Build(desktopopenfiledata_tmp, "Exec=", filename, " open %f\nPath=", pathname, "\n");
 	f = fopen("powdertoy-tpt-open.desktop", "wb");
 	if (!f)
 		return 0;
-	fwrite(desktopopenfiledata.str().c_str(), 1, strlen(desktopopenfiledata.str().c_str()), f);
+	fwrite(desktopopenfiledata.c_str(), 1, desktopopenfiledata.size(), f);
 	fclose(f);
 	success = system("xdg-mime install powdertoy-save.xml") && success;
 	success = system("xdg-desktop-menu install powdertoy-tpt-open.desktop") && success;
@@ -415,12 +413,11 @@ bool Client::DoInstallation()
 "Comment=Physics sandbox game\n"
 "Categories=Game;Simulation\n"
 "Icon=powdertoy.png\n";
-	ByteString::Stream desktopfiledata;
-	desktopfiledata << desktopfiledata_tmp << "Exec=" << filename << "\nPath=" << pathname << "\n";
+	ByteString desktopfiledata = ByteString::Build(desktopfiledata_tmp, "Exec=", filename, "\nPath=", pathname, "\n");
 	f = fopen("powdertoy-tpt.desktop", "wb");
 	if (!f)
 		return 0;
-	fwrite(desktopfiledata.str().c_str(), 1, strlen(desktopfiledata.str().c_str()), f);
+	fwrite(desktopfiledata.c_str(), 1, desktopfiledata.size(), f);
 	fclose(f);
 	success = system("xdg-desktop-menu install powdertoy-tpt.desktop") && success;
 
@@ -989,8 +986,7 @@ RequestStatus Client::UploadSave(SaveInfo & save)
 	int dataStatus;
 	char * data;
 	int dataLength = 0;
-	ByteString::Stream userIDStream;
-	userIDStream << authUser.UserID;
+	ByteString userID = ByteString::Build(authUser.UserID);
 	if (authUser.UserID)
 	{
 		if (!save.GetGameSave())
@@ -1020,13 +1016,13 @@ RequestStatus Client::UploadSave(SaveInfo & save)
 		std::strcpy (saveName, save.GetName().ToUtf8().c_str());
 		char *saveDescription = new char[save.GetDescription().length() + 1];
 		std::strcpy (saveDescription, save.GetDescription().ToUtf8().c_str());
-		char *userid = new char[userIDStream.str().length() + 1];
-		std::strcpy (userid, userIDStream.str().c_str());
+		char *userid = new char[userID.size() + 1];
+		std::strcpy (userid, userID.c_str());
 		char *session = new char[authUser.SessionID.length() + 1];
 		std::strcpy (session, authUser.SessionID.c_str());
 
 		const char *const postNames[] = { "Name", "Description", "Data:save.bin", "Publish", NULL };
-		const char *const postDatas[] = { saveName, saveDescription, gameData, (char *)(save.GetPublished()?"Public":"Private") };
+		const char *const postDatas[] = { saveName, saveDescription, gameData, save.GetPublished()?"Public":"Private" };
 		size_t postLengths[] = { save.GetName().length(), save.GetDescription().length(), gameDataLength, (size_t)(save.GetPublished()?6:7) };
 		data = http_multipart_post("http://" SERVER "/Save.api", postNames, postDatas, postLengths, userid, NULL, session, &dataStatus, &dataLength);
 
@@ -1044,7 +1040,7 @@ RequestStatus Client::UploadSave(SaveInfo & save)
 	RequestStatus ret = ParseServerReturn(data, dataStatus, false);
 	if (ret == RequestOkay)
 	{
-		int saveID = format::ByteStringToNumber<int>(data+3);
+		int saveID = ByteString(data+3).ToNumber<int>();
 		if (!saveID)
 		{
 			lastError = "Server did not return Save ID";
@@ -1100,12 +1096,8 @@ void Client::DeleteStamp(ByteString stampID)
 	{
 		if((*iterator) == stampID)
 		{
-			ByteString::Stream stampFilename;
-			stampFilename << STAMPS_DIR;
-			stampFilename << PATH_SEP;
-			stampFilename << stampID;
-			stampFilename << ".stm";
-			remove(stampFilename.str().c_str());
+			ByteString stampFilename = ByteString::Build(STAMPS_DIR, PATH_SEP, stampID, ".stm");
+			remove(stampFilename.c_str());
 			stampIDs.erase(iterator);
 			return;
 		}
@@ -1124,12 +1116,8 @@ ByteString Client::AddStamp(GameSave * saveData)
 	}
 	else
 		lastStampName++;
-	ByteString::Stream saveID;
-	//sprintf(saveID, "%08x%02x", lastStampTime, lastStampName);
-	saveID
-	<< std::setw(8) << std::setfill('0') << std::hex << lastStampTime
-	<< std::setw(2) << std::setfill('0') << std::hex << lastStampName;
-	ByteString filename = STAMPS_DIR PATH_SEP + saveID.str() + ".stm";
+	ByteString saveID = ByteString::Build(Format::Hex(Format::Width(lastStampTime, 8)), Format::Hex(Format::Width(lastStampName, 2)));
+	ByteString filename = STAMPS_DIR PATH_SEP + saveID + ".stm";
 
 	MakeDirectory(STAMPS_DIR);
 
@@ -1157,11 +1145,11 @@ ByteString Client::AddStamp(GameSave * saveData)
 
 	delete[] gameData;
 
-	stampIDs.push_front(saveID.str());
+	stampIDs.push_front(saveID);
 
 	updateStamps();
 
-	return saveID.str();
+	return saveID;
 }
 
 void Client::updateStamps()
@@ -1233,8 +1221,8 @@ RequestStatus Client::ExecVote(int saveID, int direction)
 	if (authUser.UserID)
 	{
 		char * directionText = (char*)(direction==1?"Up":"Down");
-		ByteString saveIDText = format::NumberToByteString<int>(saveID);
-		ByteString userIDText = format::NumberToByteString<int>(authUser.UserID);
+		ByteString saveIDText = ByteString::Build(saveID);
+		ByteString userIDText = ByteString::Build(authUser.UserID);
 
 		char *id = new char[saveIDText.length() + 1];
 		std::strcpy(id, saveIDText.c_str());
@@ -1267,14 +1255,14 @@ unsigned char * Client::GetSaveData(int saveID, int saveDate, int & dataLength)
 	int dataStatus;
 	char *data;
 	dataLength = 0;
-	ByteString::Stream urlStream;
+	ByteString urlStr;
 	if (saveDate)
-		urlStream << "http://" << STATICSERVER << "/" << saveID << "_" << saveDate << ".cps";
+		urlStr = ByteString::Build("http://", STATICSERVER, "/", saveID, "_", saveDate, ".cps");
 	else
-		urlStream << "http://" << STATICSERVER << "/" << saveID << ".cps";
+		urlStr = ByteString::Build("http://", STATICSERVER, "/", saveID, ".cps");
 
-	char *url = new char[urlStream.str().length() + 1];
-	std::strcpy(url, urlStream.str().c_str());
+	char *url = new char[urlStr.size() + 1];
+	std::strcpy(url, urlStr.c_str());
 	data = http_simple_get(url, &dataStatus, &dataLength);
 	delete[] url;
 
@@ -1300,13 +1288,13 @@ std::vector<unsigned char> Client::GetSaveData(int saveID, int saveDate)
 
 RequestBroker::Request * Client::GetSaveDataAsync(int saveID, int saveDate)
 {
-	ByteString::Stream urlStream;
+	ByteString url;
 	if(saveDate){
-		urlStream << "http://" << STATICSERVER << "/" << saveID << "_" << saveDate << ".cps";
+		url = ByteString::Build("http://", STATICSERVER, "/", saveID, "_", saveDate, ".cps");
 	} else {
-		urlStream << "http://" << STATICSERVER << "/" << saveID << ".cps";
+		url = ByteString::Build("http://", STATICSERVER, "/", saveID, ".cps");
 	}
-	return new WebRequest(urlStream.str());
+	return new WebRequest(url);
 }
 
 RequestBroker::Request * Client::SaveUserInfoAsync(UserInfo info)
@@ -1381,7 +1369,6 @@ RequestBroker::Request * Client::GetUserInfoAsync(ByteString username)
 LoginStatus Client::Login(ByteString username, ByteString password, User & user)
 {
 	lastError = "";
-	ByteString::Stream hashStream;
 	char passwordHash[33];
 	char totalHash[33];
 
@@ -1393,14 +1380,14 @@ LoginStatus Client::Login(ByteString username, ByteString password, User & user)
 	//Doop
 	md5_ascii(passwordHash, (const unsigned char *)password.c_str(), password.length());
 	passwordHash[32] = 0;
-	hashStream << username << "-" << passwordHash;
-	md5_ascii(totalHash, (const unsigned char *)(hashStream.str().c_str()), hashStream.str().length());
+	ByteString total = ByteString::Build(username, "-", passwordHash);
+	md5_ascii(totalHash, (const unsigned char *)(total.c_str()), total.size());
 	totalHash[32] = 0;
 
 	char * data;
 	int dataStatus, dataLength;
 	const char *const postNames[] = { "Username", "Hash", NULL };
-	const char *const postDatas[] = { (char*)username.c_str(), totalHash };
+	const char *const postDatas[] = { username.c_str(), totalHash };
 	size_t postLengths[] = { username.length(), 32 };
 	data = http_multipart_post("http://" SERVER "/Login.json", postNames, postDatas, postLengths, NULL, NULL, NULL, &dataStatus, &dataLength);
 	RequestStatus ret = ParseServerReturn(data, dataStatus, true);
@@ -1454,15 +1441,13 @@ LoginStatus Client::Login(ByteString username, ByteString password, User & user)
 RequestStatus Client::DeleteSave(int saveID)
 {
 	lastError = "";
-	ByteString::Stream urlStream;
 	char * data = NULL;
 	int dataStatus, dataLength;
-	urlStream << "http://" << SERVER << "/Browse/Delete.json?ID=" << saveID << "&Mode=Delete&Key=" << authUser.SessionKey;
+	ByteString url = ByteString::Build("http://", SERVER, "/Browse/Delete.json?ID=", saveID, "&Mode=Delete&Key=", authUser.SessionKey);
 	if(authUser.UserID)
 	{
-		ByteString::Stream userIDStream;
-		userIDStream << authUser.UserID;
-		data = http_auth_get((char *)urlStream.str().c_str(), (char *)(userIDStream.str().c_str()), NULL, (char *)(authUser.SessionID.c_str()), &dataStatus, &dataLength);
+		ByteString userID = ByteString::Build(authUser.UserID);
+		data = http_auth_get(url.c_str(), userID.c_str(), NULL, authUser.SessionID.c_str(), &dataStatus, &dataLength);
 	}
 	else
 	{
@@ -1477,19 +1462,18 @@ RequestStatus Client::DeleteSave(int saveID)
 RequestStatus Client::AddComment(int saveID, String comment)
 {
 	lastError = "";
-	ByteString::Stream urlStream;
 	char * data = NULL;
 	int dataStatus, dataLength;
-	urlStream << "http://" << SERVER << "/Browse/Comments.json?ID=" << saveID;
+	ByteString url = ByteString::Build("http://", SERVER, "/Browse/Comments.json?ID=", saveID);
 	if(authUser.UserID)
 	{
-		ByteString::Stream userIDStream;
-		userIDStream << authUser.UserID;
+		ByteString userID = ByteString::Build(authUser.UserID);
 
 		const char *const postNames[] = { "Comment", NULL };
-		const char *const postDatas[] = { (char*)(comment.c_str()) };
-		size_t postLengths[] = { comment.length() };
-		data = http_multipart_post((char *)urlStream.str().c_str(), postNames, postDatas, postLengths, (char *)(userIDStream.str().c_str()), NULL, (char *)(authUser.SessionID.c_str()), &dataStatus, &dataLength);
+		ByteString commentBytes = comment.ToUtf8();
+		const char *const postDatas[] = { commentBytes.c_str() };
+		size_t postLengths[] = { commentBytes.size() };
+		data = http_multipart_post(url.c_str(), postNames, postDatas, postLengths, userID.c_str(), NULL, authUser.SessionID.c_str(), &dataStatus, &dataLength);
 	}
 	else
 	{
@@ -1504,7 +1488,7 @@ RequestStatus Client::AddComment(int saveID, String comment)
 RequestStatus Client::FavouriteSave(int saveID, bool favourite)
 {
 	lastError = "";
-	ByteString::Stream urlStream;
+	ByteStringBuilder urlStream;
 	char * data = NULL;
 	int dataStatus, dataLength;
 	urlStream << "http://" << SERVER << "/Browse/Favourite.json?ID=" << saveID << "&Key=" << authUser.SessionKey;
@@ -1512,9 +1496,8 @@ RequestStatus Client::FavouriteSave(int saveID, bool favourite)
 		urlStream << "&Mode=Remove";
 	if(authUser.UserID)
 	{
-		ByteString::Stream userIDStream;
-		userIDStream << authUser.UserID;
-		data = http_auth_get((char *)urlStream.str().c_str(), (char *)(userIDStream.str().c_str()), NULL, (char *)(authUser.SessionID.c_str()), &dataStatus, &dataLength);
+		ByteString userID = ByteString::Build(authUser.UserID);
+		data = http_auth_get(urlStream.Build().c_str(), userID.c_str(), NULL, authUser.SessionID.c_str(), &dataStatus, &dataLength);
 	}
 	else
 	{
@@ -1529,19 +1512,18 @@ RequestStatus Client::FavouriteSave(int saveID, bool favourite)
 RequestStatus Client::ReportSave(int saveID, String message)
 {
 	lastError = "";
-	ByteString::Stream urlStream;
 	char * data = NULL;
 	int dataStatus, dataLength;
-	urlStream << "http://" << SERVER << "/Browse/Report.json?ID=" << saveID << "&Key=" << authUser.SessionKey;
+	ByteString url = ByteString::Build("http://", SERVER, "/Browse/Report.json?ID=", saveID, "&Key=", authUser.SessionKey);
 	if(authUser.UserID)
 	{
-		ByteString::Stream userIDStream;
-		userIDStream << authUser.UserID;
+		ByteString userID = ByteString::Build(authUser.UserID);
 
 		const char *const postNames[] = { "Reason", NULL };
-		const char *const postDatas[] = { (char*)(message.c_str()) };
-		size_t postLengths[] = { message.length() };
-		data = http_multipart_post((char *)urlStream.str().c_str(), postNames, postDatas, postLengths, (char *)(userIDStream.str().c_str()), NULL, (char *)(authUser.SessionID.c_str()), &dataStatus, &dataLength);
+		ByteString messageBytes = message.ToUtf8();
+		const char *const postDatas[] = { messageBytes.c_str() };
+		size_t postLengths[] = { messageBytes.size() };
+		data = http_multipart_post(url.c_str(), postNames, postDatas, postLengths, userID.c_str(), NULL, authUser.SessionID.c_str(), &dataStatus, &dataLength);
 	}
 	else
 	{
@@ -1556,15 +1538,14 @@ RequestStatus Client::ReportSave(int saveID, String message)
 RequestStatus Client::UnpublishSave(int saveID)
 {
 	lastError = "";
-	ByteString::Stream urlStream;
 	char * data = NULL;
 	int dataStatus, dataLength;
-	urlStream << "http://" << SERVER << "/Browse/Delete.json?ID=" << saveID << "&Mode=Unpublish&Key=" << authUser.SessionKey;
+	ByteString url = ByteString::Build("http://", SERVER, "/Browse/Delete.json?ID=", saveID, "&Mode=Unpublish&Key=", authUser.SessionKey);
 	if(authUser.UserID)
 	{
-		ByteString::Stream userIDStream;
-		userIDStream << authUser.UserID;
-		data = http_auth_get((char *)urlStream.str().c_str(), (char *)(userIDStream.str().c_str()), NULL, (char *)(authUser.SessionID.c_str()), &dataStatus, &dataLength);
+		ByteString userID = ByteString::Build(authUser.UserID);
+		
+		data = http_auth_get(url.c_str(), userID.c_str(), NULL, authUser.SessionID.c_str(), &dataStatus, &dataLength);
 	}
 	else
 	{
@@ -1579,18 +1560,17 @@ RequestStatus Client::UnpublishSave(int saveID)
 RequestStatus Client::PublishSave(int saveID)
 {
 	lastError = "";
-	ByteString::Stream urlStream;
 	char *data;
 	int dataStatus;
-	urlStream << "http://" << SERVER << "/Browse/View.json?ID=" << saveID << "&Key=" << authUser.SessionKey;
+	ByteString url = ByteString::Build("http://", SERVER, "/Browse/View.json?ID=", saveID, "&Key=", authUser.SessionKey);
 	if (authUser.UserID)
 	{
-		ByteString::Stream userIDStream;
-		userIDStream << authUser.UserID;
+		ByteString userID = ByteString::Build(authUser.UserID);
+		
 		const char *const postNames[] = { "ActionPublish", NULL };
 		const char *const postDatas[] = { "" };
-		size_t postLengths[] = { 1 };
-		data = http_multipart_post(urlStream.str().c_str(), postNames, postDatas, postLengths, userIDStream.str().c_str(), NULL, authUser.SessionID.c_str(), &dataStatus, NULL);	}
+		size_t postLengths[] = { 0 };
+		data = http_multipart_post(url.c_str(), postNames, postDatas, postLengths, userID.c_str(), NULL, authUser.SessionID.c_str(), &dataStatus, NULL);	}
 	else
 	{
 		lastError = "Not authenticated";
@@ -1604,7 +1584,7 @@ RequestStatus Client::PublishSave(int saveID)
 SaveInfo * Client::GetSave(int saveID, int saveDate)
 {
 	lastError = "";
-	ByteString::Stream urlStream;
+	ByteStringBuilder urlStream;
 	urlStream << "http://" << SERVER  << "/Browse/View.json?ID=" << saveID;
 	if(saveDate)
 	{
@@ -1614,13 +1594,13 @@ SaveInfo * Client::GetSave(int saveID, int saveDate)
 	int dataStatus, dataLength;
 	if(authUser.UserID)
 	{
-		ByteString::Stream userIDStream;
-		userIDStream << authUser.UserID;
-		data = http_auth_get((char *)urlStream.str().c_str(), (char *)(userIDStream.str().c_str()), NULL, (char *)(authUser.SessionID.c_str()), &dataStatus, &dataLength);
+		ByteString userID = ByteString::Build(authUser.UserID);
+		
+		data = http_auth_get(urlStream.Build().c_str(), userID.c_str(), NULL, authUser.SessionID.c_str(), &dataStatus, &dataLength);
 	}
 	else
 	{
-		data = http_simple_get((char *)urlStream.str().c_str(), &dataStatus, &dataLength);
+		data = http_simple_get(urlStream.Build().c_str(), &dataStatus, &dataLength);
 	}
 	if(dataStatus == 200 && data)
 	{
@@ -1677,7 +1657,7 @@ SaveInfo * Client::GetSave(int saveID, int saveDate)
 
 RequestBroker::Request * Client::GetSaveAsync(int saveID, int saveDate)
 {
-	ByteString::Stream urlStream;
+	ByteStringBuilder urlStream;
 	urlStream << "http://" << SERVER  << "/Browse/View.json?ID=" << saveID;
 	if(saveDate)
 	{
@@ -1734,7 +1714,7 @@ RequestBroker::Request * Client::GetSaveAsync(int saveID, int saveDate)
 		}
 		virtual ~SaveInfoParser() { }
 	};
-	return new APIRequest(urlStream.str(), new SaveInfoParser());
+	return new APIRequest(urlStream.Build(), new SaveInfoParser());
 }
 
 RequestBroker::Request * Client::GetCommentsAsync(int saveID, int start, int count)
@@ -1752,7 +1732,7 @@ RequestBroker::Request * Client::GetCommentsAsync(int saveID, int start, int cou
 
 				for (Json::UInt j = 0; j < commentsArray.size(); j++)
 				{
-					int userID = format::ByteStringToNumber<int>(commentsArray[j]["UserID"].asString());
+					int userID = ByteString(commentsArray[j]["UserID"].asString()).ToNumber<int>();
 					ByteString username = commentsArray[j]["Username"].asString();
 					ByteString formattedUsername = commentsArray[j]["FormattedUsername"].asString();
 					if (formattedUsername == "jacobot")
@@ -1775,9 +1755,8 @@ RequestBroker::Request * Client::GetCommentsAsync(int saveID, int start, int cou
 		virtual ~CommentsParser() { }
 	};
 
-	ByteString::Stream urlStream;
-	urlStream << "http://" << SERVER << "/Browse/Comments.json?ID=" << saveID << "&Start=" << start << "&Count=" << count;
-	return new APIRequest(urlStream.str(), new CommentsParser());
+	ByteString url = ByteString::Build("http://", SERVER, "/Browse/Comments.json?ID=", saveID, "&Start=", start, "&Count=", count);
+	return new APIRequest(url, new CommentsParser());
 }
 
 std::vector<std::pair<ByteString, int> > * Client::GetTags(int start, int count, String query, int & resultCount)
@@ -1785,7 +1764,7 @@ std::vector<std::pair<ByteString, int> > * Client::GetTags(int start, int count,
 	lastError = "";
 	resultCount = 0;
 	std::vector<std::pair<ByteString, int> > * tagArray = new std::vector<std::pair<ByteString, int> >();
-	ByteString::Stream urlStream;
+	ByteStringBuilder urlStream;
 	char * data;
 	int dataStatus, dataLength;
 	urlStream << "http://" << SERVER << "/Browse/Tags.json?Start=" << start << "&Count=" << count;
@@ -1796,7 +1775,7 @@ std::vector<std::pair<ByteString, int> > * Client::GetTags(int start, int count,
 			urlStream << format::URLEncode(query.ToUtf8());
 	}
 
-	data = http_simple_get((char *)urlStream.str().c_str(), &dataStatus, &dataLength);
+	data = http_simple_get(urlStream.Build().c_str(), &dataStatus, &dataLength);
 	if(dataStatus == 200 && data)
 	{
 		try
@@ -1832,7 +1811,7 @@ std::vector<SaveInfo*> * Client::SearchSaves(int start, int count, String query,
 	lastError = "";
 	resultCount = 0;
 	std::vector<SaveInfo*> * saveArray = new std::vector<SaveInfo*>();
-	ByteString::Stream urlStream;
+	ByteStringBuilder urlStream;
 	char * data;
 	int dataStatus, dataLength;
 	urlStream << "http://" << SERVER << "/Browse.json?Start=" << start << "&Count=" << count;
@@ -1854,13 +1833,12 @@ std::vector<SaveInfo*> * Client::SearchSaves(int start, int count, String query,
 	}
 	if(authUser.UserID)
 	{
-		ByteString::Stream userIDStream;
-		userIDStream << authUser.UserID;
-		data = http_auth_get((char *)urlStream.str().c_str(), (char *)(userIDStream.str().c_str()), NULL, (char *)(authUser.SessionID.c_str()), &dataStatus, &dataLength);
+		ByteString userID = ByteString::Build(authUser.UserID);
+		data = http_auth_get(urlStream.Build().c_str(), userID.c_str(), NULL, authUser.SessionID.c_str(), &dataStatus, &dataLength);
 	}
 	else
 	{
-		data = http_simple_get((char *)urlStream.str().c_str(), &dataStatus, &dataLength);
+		data = http_simple_get(urlStream.Build().c_str(), &dataStatus, &dataLength);
 	}
 	ParseServerReturn(data, dataStatus, true);
 	if (dataStatus == 200 && data)
@@ -1917,15 +1895,13 @@ std::list<ByteString> * Client::RemoveTag(int saveID, ByteString tag)
 {
 	lastError = "";
 	std::list<ByteString> * tags = NULL;
-	ByteString::Stream urlStream;
 	char * data = NULL;
 	int dataStatus, dataLength;
-	urlStream << "http://" << SERVER << "/Browse/EditTag.json?Op=delete&ID=" << saveID << "&Tag=" << tag << "&Key=" << authUser.SessionKey;
+	ByteString url = ByteString::Build("http://", SERVER, "/Browse/EditTag.json?Op=delete&ID=", saveID, "&Tag=", tag, "&Key=", authUser.SessionKey);
 	if(authUser.UserID)
 	{
-		ByteString::Stream userIDStream;
-		userIDStream << authUser.UserID;
-		data = http_auth_get((char *)urlStream.str().c_str(), (char *)(userIDStream.str().c_str()), NULL, (char *)(authUser.SessionID.c_str()), &dataStatus, &dataLength);
+		ByteString userID = ByteString::Build(authUser.UserID);
+		data = http_auth_get(url.c_str(), userID.c_str(), NULL, authUser.SessionID.c_str(), &dataStatus, &dataLength);
 	}
 	else
 	{
@@ -1959,15 +1935,13 @@ std::list<ByteString> * Client::AddTag(int saveID, ByteString tag)
 {
 	lastError = "";
 	std::list<ByteString> * tags = NULL;
-	ByteString::Stream urlStream;
 	char * data = NULL;
 	int dataStatus, dataLength;
-	urlStream << "http://" << SERVER << "/Browse/EditTag.json?Op=add&ID=" << saveID << "&Tag=" << tag << "&Key=" << authUser.SessionKey;
+	ByteString url = ByteString::Build("http://", SERVER, "/Browse/EditTag.json?Op=add&ID=", saveID, "&Tag=", tag, "&Key=", authUser.SessionKey);
 	if(authUser.UserID)
 	{
-		ByteString::Stream userIDStream;
-		userIDStream << authUser.UserID;
-		data = http_auth_get((char *)urlStream.str().c_str(), (char *)(userIDStream.str().c_str()), NULL, (char *)(authUser.SessionID.c_str()), &dataStatus, &dataLength);
+		ByteString userID = ByteString::Build(authUser.UserID);
+		data = http_auth_get(url.c_str(), userID.c_str(), NULL, authUser.SessionID.c_str(), &dataStatus, &dataLength);
 	}
 	else
 	{
diff --git a/src/client/GameSave.cpp b/src/client/GameSave.cpp
index b7fd2af36..eff87d3df 100644
--- a/src/client/GameSave.cpp
+++ b/src/client/GameSave.cpp
@@ -629,7 +629,7 @@ void GameSave::readOPS(char * data, int dataLength)
 	int bz2ret;
 	if ((bz2ret = BZ2_bzBuffToBuffDecompress((char*)bsonData, &bsonDataLen, (char*)(inputData+12), inputDataLen-12, 0, 0)) != BZ_OK)
 	{
-		throw ParseException(ParseException::Corrupt, "Unable to decompress (ret " + format::NumberToString<int>(bz2ret) + ")");
+		throw ParseException(ParseException::Corrupt, String::Build("Unable to decompress (ret ", bz2ret, ")"));
 	}
 
 	set_bson_err_handler([](const char* err) { throw ParseException(ParseException::Corrupt, "BSON error when parsing save: " + ByteString(err).FromUtf8()); });
@@ -1406,7 +1406,7 @@ void GameSave::readPSv(char * saveDataChar, int dataLength)
 
 	int bzStatus = 0;
 	if ((bzStatus = BZ2_bzBuffToBuffDecompress((char *)data, (unsigned *)&size, (char *)(saveData+12), dataLength-12, 0, 0)))
-		throw ParseException(ParseException::Corrupt, "Cannot decompress: " + format::NumberToString(bzStatus));
+		throw ParseException(ParseException::Corrupt, String::Build("Cannot decompress: ", bzStatus));
 	dataLength = size;
 
 #ifdef DEBUG
@@ -2510,7 +2510,7 @@ char * GameSave::serialiseOPS(unsigned int & dataLength)
 	unsigned int finalDataLen = bson_size(&b);
 	auto outputData = std::unique_ptr<unsigned char[]>(new unsigned char[finalDataLen*2+12]);
 	if (!outputData)
-		throw BuildException("Save error, out of memory (finalData): " + format::NumberToString<unsigned int>(finalDataLen*2+12));
+		throw BuildException(String::Build("Save error, out of memory (finalData): ", finalDataLen*2+12));
 
 	outputData[0] = 'O';
 	outputData[1] = 'P';
@@ -2528,7 +2528,7 @@ char * GameSave::serialiseOPS(unsigned int & dataLength)
 	unsigned int compressedSize = finalDataLen*2, bz2ret;
 	if ((bz2ret = BZ2_bzBuffToBuffCompress((char*)(outputData.get()+12), &compressedSize, (char*)finalData, bson_size(&b), 9, 0, 0)) != BZ_OK)
 	{
-		throw BuildException("Save error, could not compress (ret " + format::NumberToString<int>(bz2ret) + ")");
+		throw BuildException(String::Build("Save error, could not compress (ret ", bz2ret, ")"));
 	}
 
 #ifdef DEBUG
diff --git a/src/client/HTTP.cpp b/src/client/HTTP.cpp
index 26da8f496..899122924 100644
--- a/src/client/HTTP.cpp
+++ b/src/client/HTTP.cpp
@@ -192,11 +192,7 @@ void http_init(char *proxy)
 		free(host);
 		free(port);
 	}
-	ByteString::Stream userAgentBuilder;
-	userAgentBuilder << "PowderToy/" << SAVE_VERSION << "." << MINOR_VERSION << " ";
-	userAgentBuilder << "(" << IDENT_PLATFORM << "; " << IDENT_BUILD << "; M" << MOD_ID << ") ";
-	userAgentBuilder << "TPTPP/" << SAVE_VERSION << "." << MINOR_VERSION << "." << BUILD_NUM << IDENT_RELTYPE << "." << SNAPSHOT_ID;
-	ByteString newUserAgent = userAgentBuilder.str();
+	ByteString newUserAgent = ByteString::Build("PowderToy/", SAVE_VERSION, ".", MINOR_VERSION, " (", IDENT_PLATFORM, "; ", IDENT_BUILD, "; M", MOD_ID, ") TPTPP/", SAVE_VERSION, ".", MINOR_VERSION, ".", BUILD_NUM, IDENT_RELTYPE, ".", SNAPSHOT_ID);
 	userAgent = new char[newUserAgent.length()+1];
 	std::copy(newUserAgent.begin(), newUserAgent.end(), userAgent);
 	userAgent[newUserAgent.length()] = 0;
@@ -987,7 +983,7 @@ ByteString FindBoundary(std::map<ByteString, ByteString> parts, ByteString bound
 // this function used in Download class, and eventually all http requests
 ByteString GetMultipartMessage(std::map<ByteString, ByteString> parts, ByteString boundary)
 {
-	ByteString::Stream data;
+	ByteStringBuilder data;
 
 	// loop through each part, adding it
 	for (std::map<ByteString, ByteString>::iterator iter = parts.begin(); iter != parts.end(); iter++)
@@ -1014,7 +1010,7 @@ ByteString GetMultipartMessage(std::map<ByteString, ByteString> parts, ByteStrin
 		data << "\r\n";
 	}
 	data << "--" << boundary << "--\r\n";
-	return data.str();
+	return data.Build();
 }
 
 // add the header needed to make POSTS work
diff --git a/src/client/requestbroker/APIRequest.cpp b/src/client/requestbroker/APIRequest.cpp
index dcd2e143a..084e580c9 100644
--- a/src/client/requestbroker/APIRequest.cpp
+++ b/src/client/requestbroker/APIRequest.cpp
@@ -103,7 +103,7 @@ RequestBroker::ProcessResponse APIRequest::Process(RequestBroker & rb)
 				User user = Client::Ref().GetAuthUser();
 				char userName[12];
 				char *userSession = new char[user.SessionID.length() + 1];
-				std::strcpy(userName, format::NumberToByteString<int>(user.UserID).c_str());
+				std::strcpy(userName, ByteString::Build(user.UserID).c_str());
 				std::strcpy(userSession, user.SessionID.c_str());
 				HTTPContext = http_multipart_post_async((char*)URL.c_str(), postNames, postData, postLength, userName, NULL, userSession);
 				delete[] userSession;
@@ -122,7 +122,7 @@ RequestBroker::ProcessResponse APIRequest::Process(RequestBroker & rb)
 				User user = Client::Ref().GetAuthUser();
 				char userName[12];
 				char *userSession = new char[user.SessionID.length() + 1];
-				std::strcpy(userName, format::NumberToByteString<int>(user.UserID).c_str());
+				std::strcpy(userName, ByteString::Build(user.UserID).c_str());
 				std::strcpy(userSession, user.SessionID.c_str());
 				http_auth_headers(HTTPContext, userName, NULL, userSession);
 				delete[] userSession;
diff --git a/src/client/requestbroker/RequestBroker.cpp b/src/client/requestbroker/RequestBroker.cpp
index b3395e78e..5a446a754 100644
--- a/src/client/requestbroker/RequestBroker.cpp
+++ b/src/client/requestbroker/RequestBroker.cpp
@@ -97,23 +97,22 @@ void RequestBroker::RenderThumbnail(GameSave * gameSave, bool decorations, bool
 
 void RequestBroker::RetrieveThumbnail(int saveID, int saveDate, int width, int height, RequestListener * tListener)
 {
-	ByteString::Stream urlStream;
-	urlStream << "http://" << STATICSERVER << "/" << saveID;
+	ByteStringBuilder url;
+	url << "http://" << STATICSERVER << "/" << saveID;
 	if(saveDate)
 	{
-		urlStream << "_" << saveDate;
+		url << "_" << saveDate;
 	}
-	urlStream << "_small.pti";
+	url << "_small.pti";
 
-	RetrieveImage(urlStream.str(), width, height, tListener);
+	RetrieveImage(url.Build(), width, height, tListener);
 }
 
 void RequestBroker::RetrieveAvatar(ByteString username, int width, int height, RequestListener * tListener)
 {
-	ByteString::Stream urlStream;
-	urlStream << "http://" << STATICSERVER << "/avatars/" << username << ".pti";
+	ByteString url = ByteString::Build("http://", STATICSERVER, "/avatars/", username, ".pti");
 
-	RetrieveImage(urlStream.str(), width, height, tListener);
+	RetrieveImage(url, width, height, tListener);
 }
 
 void RequestBroker::Start(Request * request, RequestListener * tListener, int identifier)
diff --git a/src/client/requestbroker/WebRequest.cpp b/src/client/requestbroker/WebRequest.cpp
index bd8b99ea9..c72b130d0 100644
--- a/src/client/requestbroker/WebRequest.cpp
+++ b/src/client/requestbroker/WebRequest.cpp
@@ -106,7 +106,7 @@ RequestBroker::ProcessResponse WebRequest::Process(RequestBroker & rb)
 				User user = Client::Ref().GetAuthUser();
 				char userName[12];
 				char *userSession = new char[user.SessionID.length() + 1];
-				std::strcpy(userName, format::NumberToByteString<int>(user.UserID).c_str());
+				std::strcpy(userName, ByteString::Build(user.UserID).c_str());
 				std::strcpy(userSession, user.SessionID.c_str());
 				HTTPContext = http_multipart_post_async((char*)URL.c_str(), postNames, postData, postLength, userName, NULL, userSession);
 				delete[] userSession;
@@ -125,7 +125,7 @@ RequestBroker::ProcessResponse WebRequest::Process(RequestBroker & rb)
 				User user = Client::Ref().GetAuthUser();
 				char userName[12];
 				char *userSession = new char[user.SessionID.length() + 1];
-				std::strcpy(userName, format::NumberToByteString<int>(user.UserID).c_str());
+				std::strcpy(userName, ByteString::Build(user.UserID).c_str());
 				std::strcpy(userSession, user.SessionID.c_str());
 				http_auth_headers(HTTPContext, userName, NULL, userSession);
 				delete[] userSession;
diff --git a/src/common/Format.h b/src/common/Format.h
index 3e76d2fab..e5afe1eae 100644
--- a/src/common/Format.h
+++ b/src/common/Format.h
@@ -25,6 +25,18 @@ namespace Format
 		inline FlagsOverride() {}
 	};
 
+	template<typename T> struct FillOverride
+	{
+		T value;
+		size_t fill;
+		inline FillOverride(T _value, size_t _fill): value(_value), fill(_fill) {}
+	};
+	template<> struct FillOverride<void>
+	{
+		String::value_type fill;
+		inline FillOverride(size_t _fill): fill(_fill) {}
+	};
+
 	template<typename T> struct WidthOverride
 	{
 		T value;
@@ -74,8 +86,10 @@ namespace Format
 	inline FlagsOverride<void, std::ios_base::scientific, std::ios_base::floatfield> Scientific() { return FlagsOverride<void, std::ios_base::scientific, std::ios_base::floatfield>(); }
 	inline FlagsOverride<void, std::ios_base::fmtflags{}, std::ios_base::floatfield> FloatDefault() { return FlagsOverride<void, std::ios_base::fmtflags{}, std::ios_base::floatfield>(); }
 
+	template<typename T> inline FillOverride<T> Fill(T value, String::value_type fill) { return FillOverride<T>(value, fill); }
 	template<typename T> inline WidthOverride<T> Width(T value, size_t width) { return WidthOverride<T>(value, width); }
 	template<typename T> inline PrecisionOverride<T> Precision(T value, size_t precision) { return PrecisionOverride<T>(value, precision); }
+	inline FillOverride<void> Fill(String::value_type fill) { return FillOverride<void>(fill); }
 	inline WidthOverride<void> Width(size_t width) { return WidthOverride<void>(width); }
 	inline PrecisionOverride<void> Precision(size_t precision) { return PrecisionOverride<void>(precision); }
 };
@@ -94,16 +108,36 @@ template<std::ios_base::fmtflags set, std::ios_base::fmtflags reset> inline Byte
 	return b;
 }
 
+template<typename T> inline ByteStringBuilder &operator<<(ByteStringBuilder &b, Format::FillOverride<T> data)
+{
+	size_t oldfill = b.fill;
+	b.fill = data.fill;
+	b << data.value;
+	b.fill = oldfill;
+	return b;
+}
+inline ByteStringBuilder &operator<<(ByteStringBuilder &b, Format::FillOverride<void> data)
+{
+	b.fill = data.fill;
+	return b;
+}
+
 template<typename T> inline ByteStringBuilder &operator<<(ByteStringBuilder &b, Format::WidthOverride<T> data)
 {
+	String::value_type oldfill = b.fill;
+	if(oldfill == ' ')
+		b.fill = '0';
 	size_t oldwidth = b.width;
 	b.width = data.width;
 	b << data.value;
 	b.width = oldwidth;
+	b.fill = oldfill;
 	return b;
 }
 inline ByteStringBuilder &operator<<(ByteStringBuilder &b, Format::WidthOverride<void> data)
 {
+	if(b.fill == ' ')
+		b.fill = '0';
 	b.width = data.width;
 	return b;
 }
@@ -142,16 +176,36 @@ template<std::ios_base::fmtflags set, std::ios_base::fmtflags reset> inline Stri
 	return b;
 }
 
+template<typename T> inline StringBuilder &operator<<(StringBuilder &b, Format::FillOverride<T> data)
+{
+	size_t oldfill = b.fill;
+	b.fill = data.fill;
+	b << data.value;
+	b.fill = oldfill;
+	return b;
+}
+inline StringBuilder &operator<<(StringBuilder &b, Format::FillOverride<void> data)
+{
+	b.fill = data.fill;
+	return b;
+}
+
 template<typename T> inline StringBuilder &operator<<(StringBuilder &b, Format::WidthOverride<T> data)
 {
+	String::value_type oldfill = b.fill;
+	if(oldfill == ' ')
+		b.fill = '0';
 	size_t oldwidth = b.width;
 	b.width = data.width;
 	b << data.value;
 	b.width = oldwidth;
+	b.fill = oldfill;
 	return b;
 }
 inline StringBuilder &operator<<(StringBuilder &b, Format::WidthOverride<void> data)
 {
+	if(b.fill == ' ')
+		b.fill = '0';
 	b.width = data.width;
 	return b;
 }
diff --git a/src/common/String.h b/src/common/String.h
index bb6be1841..4ac454a17 100644
--- a/src/common/String.h
+++ b/src/common/String.h
@@ -168,8 +168,6 @@ public:
 	String FromUtf8(bool ignoreError = true) const;
 	inline String FromAscii() const;
 	template<typename... Ts> static ByteString Build(Ts&&... args);
-
-	using Stream = std::basic_stringstream<value_type>;
 };
 
 inline ByteString operator+(ByteString const &lhs, ByteString const &rhs) { return static_cast<std::basic_string<char> const &>(lhs) + static_cast<std::basic_string<char> const &>(rhs); }
@@ -405,7 +403,7 @@ public:
 	size_t Size() const { return buffer.size(); }
 	ByteString Build() const;
 
-	template<typename T> ByteStringBuilder &operator<<(T) = delete;
+	template<typename T> ByteStringBuilder &operator<<(T) &&= delete;
 
 	template<typename T, typename... Ts> ByteStringBuilder &Add(T &&arg, Ts&&... args)
 	{
diff --git a/src/debug/ElementPopulation.cpp b/src/debug/ElementPopulation.cpp
index 3de462a11..c9739bd84 100644
--- a/src/debug/ElementPopulation.cpp
+++ b/src/debug/ElementPopulation.cpp
@@ -37,8 +37,8 @@ void ElementPopulationDebug::Draw()
 	maxAverage = (maxAverage*(1.0f-0.015f)) + (0.015f*maxVal);
 	scale = 255.0f/maxAverage;
 
-	maxValString = format::NumberToString<int>(maxAverage);
-	halfValString = format::NumberToString<int>(maxAverage/2);
+	maxValString = String::Build(maxAverage);
+	halfValString = String::Build(maxAverage/2);
 
 
 	g->fillrect(xStart-5, yBottom - 263, bars+10+Graphics::textwidth(maxValString)+10, 255 + 13, 0, 0, 0, 180);
diff --git a/src/gui/colourpicker/ColourPickerActivity.cpp b/src/gui/colourpicker/ColourPickerActivity.cpp
index a3bef8f23..93c58b378 100644
--- a/src/gui/colourpicker/ColourPickerActivity.cpp
+++ b/src/gui/colourpicker/ColourPickerActivity.cpp
@@ -28,10 +28,10 @@ ColourPickerActivity::ColourPickerActivity(ui::Colour initialColour, ColourPicke
 		void TextChangedCallback(ui::Textbox * sender)
 		{
 			int r, g, b, alpha;
-			r = format::StringToNumber<int>(a->rValue->GetText());
-			g = format::StringToNumber<int>(a->gValue->GetText());
-			b = format::StringToNumber<int>(a->bValue->GetText());
-			alpha = format::StringToNumber<int>(a->aValue->GetText());
+			r = a->rValue->GetText().ToNumber<int>(true);
+			g = a->gValue->GetText().ToNumber<int>(true);
+			b = a->bValue->GetText().ToNumber<int>(true);
+			alpha = a->aValue->GetText().ToNumber<int>(true);
 			if (r > 255)
 				r = 255;
 			if (g > 255)
@@ -82,9 +82,9 @@ ColourPickerActivity::ColourPickerActivity(ui::Colour initialColour, ColourPicke
 		void ActionCallback(ui::Button * sender)
 		{
 			int Red, Green, Blue;
-			Red = format::StringToNumber<int>(a->rValue->GetText());
-			Green = format::StringToNumber<int>(a->gValue->GetText());
-			Blue = format::StringToNumber<int>(a->bValue->GetText());
+			Red = a->rValue->GetText().ToNumber<int>(true);
+			Green = a->gValue->GetText().ToNumber<int>(true);
+			Blue = a->bValue->GetText().ToNumber<int>(true);
 			ui::Colour col(Red, Green, Blue, a->currentAlpha);
 			if(a->callback)
 				a->callback->ColourPicked(col);
@@ -104,10 +104,10 @@ ColourPickerActivity::ColourPickerActivity(ui::Colour initialColour, ColourPicke
 
 void ColourPickerActivity::UpdateTextboxes(int r, int g, int b, int a)
 {
-	rValue->SetText(format::NumberToString<int>(r));
-	gValue->SetText(format::NumberToString<int>(g));
-	bValue->SetText(format::NumberToString<int>(b));
-	aValue->SetText(format::NumberToString<int>(a));
+	rValue->SetText(String::Build(r));
+	gValue->SetText(String::Build(g));
+	bValue->SetText(String::Build(b));
+	aValue->SetText(String::Build(a));
 	hexValue->SetText(String::Build(Format::Hex(), Format::Uppercase(), Format::Width(2), a, r, g, b));
 }
 void ColourPickerActivity::OnTryExit(ExitMethod method)
diff --git a/src/gui/dialogues/SaveIDMessage.cpp b/src/gui/dialogues/SaveIDMessage.cpp
index 2969708c8..53b922f04 100644
--- a/src/gui/dialogues/SaveIDMessage.cpp
+++ b/src/gui/dialogues/SaveIDMessage.cpp
@@ -28,8 +28,8 @@ SaveIDMessage::SaveIDMessage(int id):
 	copyTextLabel->Appearance.HorizontalAlign = ui::Appearance::AlignCentre;
 	AddComponent(copyTextLabel);
 
-	textWidth = Graphics::textwidth(format::NumberToString<int>(id).c_str());
-	ui::CopyTextButton * copyTextButton = new ui::CopyTextButton(ui::Point((Size.X-textWidth-10)/2, 50), ui::Point(textWidth+10, 18), format::NumberToString<int>(id), copyTextLabel);
+	textWidth = Graphics::textwidth(String::Build(id));
+	ui::CopyTextButton * copyTextButton = new ui::CopyTextButton(ui::Point((Size.X-textWidth-10)/2, 50), ui::Point(textWidth+10, 18), String::Build(id), copyTextLabel);
 	AddComponent(copyTextButton);
 
 	class DismissAction: public ui::ButtonAction
diff --git a/src/gui/font/FontEditor.cpp b/src/gui/font/FontEditor.cpp
index 82a761f60..79d84517f 100644
--- a/src/gui/font/FontEditor.cpp
+++ b/src/gui/font/FontEditor.cpp
@@ -293,9 +293,7 @@ FontEditor::FontEditor(ByteString _header):
 		CharNumberAction(FontEditor *_v): v(_v) {}
 		void TextChangedCallback(ui::Textbox *)
 		{
-			unsigned int number;
-			ByteString::Stream ss(v->currentCharTextbox->GetText().ToUtf8());
-			ss >> std::hex >> number;
+			unsigned int number = v->currentCharTextbox->GetText().ToNumber<unsigned int>(true);
 			if(number <= 0x10FFFF)
 				v->currentChar = number;
 		}
@@ -426,14 +424,13 @@ FontEditor::FontEditor(ByteString _header):
 		ColorComponentAction(int &_color): color(_color) {}
 		void TextChangedCallback(ui::Textbox *box)
 		{
-			ByteString::Stream ss(box->GetText().ToUtf8());
-			ss >> color;
+			color = box->GetText().ToNumber<int>(true);
 		}
 	};
 	int *refs[6] = {&fgR, &fgG, &fgB, &bgR, &bgG, &bgB};
 	for(int i = 0; i < 6; i++)
 	{
-		ui::Textbox *colorComponent = new ui::Textbox(ui::Point(currentX, baseline), ui::Point(27, 17), format::NumberToString(*refs[i]));
+		ui::Textbox *colorComponent = new ui::Textbox(ui::Point(currentX, baseline), ui::Point(27, 17), String::Build(*refs[i]));
 		currentX += 28;
 		colorComponent->SetActionCallback(new ColorComponentAction(*refs[i]));
 		AddComponent(colorComponent);
@@ -489,28 +486,26 @@ FontEditor::FontEditor(ByteString _header):
 		PreviewAction(FontEditor *_v): v(_v) {}
 		void TextChangedCallback(ui::Textbox *box)
 		{
-			ByteString::Stream ss(box->GetText().ToUtf8()); // ByteString::Stream for now
-			String text;
-			while(!ss.eof())
+			String str = box->GetText();
+			size_t at = 0;
+			StringBuilder text;
+			while(at < str.size())
 			{
-				if(ss.peek() == '\n')
-				{
-					text.push_back('\n');
-					ss.get();
-				}
 				unsigned int ch;
-				ss >> std::hex >> ch;
-				if(ss.fail())
-				{
-					ss.clear();
-					String::value_type ch = ss.get();
-					if(!ss.eof())
-						text.push_back(ch);
-					continue;
-				}
-				text.push_back(ch);
+				if(str[at] != ' ')
+					if(String::Split split = str.SplitNumber(ch, Format::Hex(), at))
+					{
+						text << String::value_type(ch);
+						at = split.PositionAfter();
+					}
+					else
+					{
+						text << str[at++];
+					}
+				else
+					at++;
 			}
-			v->outputPreview->SetText(text);
+			v->outputPreview->SetText(text.Build());
 		}
 	};
 	ui::Textbox *inputPreview = new ui::Textbox(ui::Point(0, baseline), ui::Point(Size.X, (Size.Y - baseline) * 3 / 5));
@@ -611,9 +606,7 @@ void FontEditor::OnKeyPress(int key, Uint16 character, bool shift, bool ctrl, bo
 
 void FontEditor::UpdateCharNumber()
 {
-	ByteString::Stream ss;
-	ss << std::hex << currentChar;
-	currentCharTextbox->SetText(ByteString(ss.str()).FromUtf8());
+	currentCharTextbox->SetText(String::Build(Format::Hex((unsigned int)currentChar)));
 }
 
 void FontEditor::PrevChar()
diff --git a/src/gui/game/GameController.cpp b/src/gui/game/GameController.cpp
index f82dc4a5d..cdc60911d 100644
--- a/src/gui/game/GameController.cpp
+++ b/src/gui/game/GameController.cpp
@@ -679,7 +679,7 @@ bool GameController::MouseUp(int x, int y, unsigned button, char type)
 						{
 						case 'c':
 						{
-							int saveID = format::StringToNumber<int>(link);
+							int saveID = link.ToNumber<int>(true);
 							if (saveID)
 								OpenSavePreview(saveID, 0, false);
 							break;
@@ -687,9 +687,7 @@ bool GameController::MouseUp(int x, int y, unsigned button, char type)
 						case 't':
 						{
 							// buff is already confirmed to be a number by sign::splitsign
-							ByteString::Stream uri;
-							uri << "http://powdertoy.co.uk/Discussions/Thread/View.html?Thread=" << link.ToUtf8();
-							Platform::OpenURI(uri.str());
+							Platform::OpenURI(ByteString::Build("http://powdertoy.co.uk/Discussions/Thread/View.html?Thread=", link.ToUtf8()));
 							break;
 						}
 						case 's':
diff --git a/src/gui/game/GameView.cpp b/src/gui/game/GameView.cpp
index 37b95e3c9..e0a7bc58e 100644
--- a/src/gui/game/GameView.cpp
+++ b/src/gui/game/GameView.cpp
@@ -1060,10 +1060,8 @@ int GameView::Record(bool record)
 		{
 			time_t startTime = time(NULL);
 			recordingFolder = startTime;
-			ByteString::Stream recordingDir;
-			recordingDir << "recordings" << PATH_SEP << recordingFolder;
 			Client::Ref().MakeDirectory("recordings");
-			Client::Ref().MakeDirectory(recordingDir.str().c_str());
+			Client::Ref().MakeDirectory(ByteString::Build("recordings", PATH_SEP, recordingFolder).c_str());
 			recording = true;
 			recordingIndex = 0;
 		}
@@ -2211,12 +2209,9 @@ void GameView::OnDraw()
 			VideoBuffer screenshot(ren->DumpFrame());
 			std::vector<char> data = format::VideoBufferToPNG(screenshot);
 
-			ByteString::Stream filename;
-			filename << "screenshot_";
-			filename << std::setfill('0') << std::setw(6) << (screenshotIndex++);
-			filename << ".png";
+			ByteString filename = ByteString::Build("screenshot_", Format::Width(screenshotIndex++, 6), ".png");
 
-			Client::Ref().WriteFile(data, filename.str());
+			Client::Ref().WriteFile(data, filename);
 			doScreenshot = false;
 		}
 
@@ -2225,13 +2220,9 @@ void GameView::OnDraw()
 			VideoBuffer screenshot(ren->DumpFrame());
 			std::vector<char> data = format::VideoBufferToPPM(screenshot);
 
-			ByteString::Stream filename;
-			filename << "recordings" << PATH_SEP << recordingFolder << PATH_SEP;
-			filename << "frame_";
-			filename << std::setfill('0') << std::setw(6) << (recordingIndex++);
-			filename << ".ppm";
+			ByteString filename = ByteString::Build("recordings", PATH_SEP, recordingFolder, PATH_SEP, "frame_", Format::Width(screenshotIndex++, 6), ".ppm");
 
-			Client::Ref().WriteFile(data, filename.str());
+			Client::Ref().WriteFile(data, filename);
 		}
 
 		if (logEntries.size())
diff --git a/src/gui/interface/SaveButton.cpp b/src/gui/interface/SaveButton.cpp
index 8fd9aef2c..1dc93a46a 100644
--- a/src/gui/interface/SaveButton.cpp
+++ b/src/gui/interface/SaveButton.cpp
@@ -40,7 +40,7 @@ SaveButton::SaveButton(Point position, Point size, SaveInfo * save):
 
 		String votes, icon;
 
-		votes = format::NumberToString<int>(save->GetVotesUp()-save->GetVotesDown());
+		votes = String::Build(save->GetVotesUp()-save->GetVotesDown());
 		icon += 0xE03B;
 		for (size_t j = 1; j < votes.length(); j++)
 			icon += 0xE03C;
diff --git a/src/gui/localbrowser/LocalBrowserView.cpp b/src/gui/localbrowser/LocalBrowserView.cpp
index 1a87a42e1..850264d07 100644
--- a/src/gui/localbrowser/LocalBrowserView.cpp
+++ b/src/gui/localbrowser/LocalBrowserView.cpp
@@ -108,11 +108,11 @@ LocalBrowserView::LocalBrowserView():
 
 void LocalBrowserView::textChanged()
 {
-	int num = format::StringToNumber<int>(pageTextbox->GetText());
+	int num = pageTextbox->GetText().ToNumber<int>(true);
 	if (num < 0) //0 is allowed so that you can backspace the 1
 		pageTextbox->SetText("1");
 	else if (num > pageCount)
-		pageTextbox->SetText(format::NumberToString(pageCount));
+		pageTextbox->SetText(String::Build(pageCount));
 	changed = true;
 #ifdef USE_SDL
 	lastChanged = GetTicks()+600;
@@ -126,7 +126,7 @@ void LocalBrowserView::OnTick(float dt)
 	if (changed && lastChanged < GetTicks())
 	{
 		changed = false;
-		c->SetPage(std::max(format::StringToNumber<int>(pageTextbox->GetText()), 0));
+		c->SetPage(std::max(pageTextbox->GetText().ToNumber<int>(true), 0));
 	}
 #endif
 }
diff --git a/src/gui/options/OptionsView.cpp b/src/gui/options/OptionsView.cpp
index a40794023..c2881d2cd 100644
--- a/src/gui/options/OptionsView.cpp
+++ b/src/gui/options/OptionsView.cpp
@@ -158,7 +158,7 @@ OptionsView::OptionsView():
 		{
 			if (current_scale == ix_scale)
 				current_scale_valid = true;
-			scale->AddOption(std::pair<String, int>(format::NumberToString<int>(ix_scale), ix_scale));
+			scale->AddOption(std::pair<String, int>(String::Build(ix_scale), ix_scale));
 			ix_scale += 1;
 		}
 		while (ui::Engine::Ref().GetMaxWidth() >= ui::Engine::Ref().GetWidth() * ix_scale && ui::Engine::Ref().GetMaxHeight() >= ui::Engine::Ref().GetHeight() * ix_scale);
@@ -233,9 +233,9 @@ OptionsView::OptionsView():
 		OptionsView * v;
 	public:
 		DepthAction(OptionsView * v_) { v = v_; }
-		virtual void TextChangedCallback(ui::Textbox * sender) { v->c->Set3dDepth(format::StringToNumber<int>(sender->GetText())); }
+		virtual void TextChangedCallback(ui::Textbox * sender) { v->c->Set3dDepth(sender->GetText().ToNumber<int>(true)); }
 	};
-	depthTextbox = new ui::Textbox(ui::Point(8, Size.Y-58), ui::Point(25, 16), format::NumberToString<int>(ui::Engine::Ref().Get3dDepth()));
+	depthTextbox = new ui::Textbox(ui::Point(8, Size.Y-58), ui::Point(25, 16), String::Build(ui::Engine::Ref().Get3dDepth()));
 	depthTextbox->SetInputType(ui::Textbox::Numeric);
 	depthTextbox->SetActionCallback(new DepthAction(this));
 	AddComponent(depthTextbox);
diff --git a/src/gui/preview/PreviewController.cpp b/src/gui/preview/PreviewController.cpp
index 44870f9d2..ea19620c7 100644
--- a/src/gui/preview/PreviewController.cpp
+++ b/src/gui/preview/PreviewController.cpp
@@ -153,9 +153,8 @@ void PreviewController::FavouriteSave()
 
 void PreviewController::OpenInBrowser()
 {
-	ByteString::Stream uriStream;
-	uriStream << "http://" << SERVER << "/Browse/View.html?ID=" << saveId;
-	Platform::OpenURI(uriStream.str());
+	ByteString uri = ByteString::Build("http://", SERVER, "/Browse/View.html?ID=", saveId);
+	Platform::OpenURI(uri);
 }
 
 bool PreviewController::NextCommentPage()
diff --git a/src/gui/preview/PreviewModel.cpp b/src/gui/preview/PreviewModel.cpp
index 5cc503e15..cb3987c12 100644
--- a/src/gui/preview/PreviewModel.cpp
+++ b/src/gui/preview/PreviewModel.cpp
@@ -70,30 +70,28 @@ void PreviewModel::UpdateSave(int saveID, int saveDate)
 	notifySaveChanged();
 	notifySaveCommentsChanged();
 
-	ByteString::Stream urlStream;
+	ByteString url;
 	if (saveDate)
-		urlStream << "http://" << STATICSERVER << "/" << saveID << "_" << saveDate << ".cps";
+		url = ByteString::Build("http://", STATICSERVER, "/", saveID, "_", saveDate, ".cps");
 	else
-		urlStream << "http://" << STATICSERVER << "/" << saveID << ".cps";
-	saveDataDownload = new Download(urlStream.str());
+		url = ByteString::Build("http://", STATICSERVER, "/", saveID, ".cps");
+	saveDataDownload = new Download(url);
 	saveDataDownload->Start();
 
-	urlStream.str("");
-	urlStream << "http://" << SERVER  << "/Browse/View.json?ID=" << saveID;
+	url = ByteString::Build("http://", SERVER , "/Browse/View.json?ID=", saveID);
 	if (saveDate)
-		urlStream << "&Date=" << saveDate;
-	saveInfoDownload = new Download(urlStream.str());
-	saveInfoDownload->AuthHeaders(format::NumberToByteString(Client::Ref().GetAuthUser().UserID), Client::Ref().GetAuthUser().SessionID);
+		url += ByteString::Build("&Date=", saveDate);
+	saveInfoDownload = new Download(url);
+	saveInfoDownload->AuthHeaders(ByteString::Build(Client::Ref().GetAuthUser().UserID), Client::Ref().GetAuthUser().SessionID);
 	saveInfoDownload->Start();
 
 	if (!GetDoOpen())
 	{
 		commentsLoaded = false;
 
-		urlStream.str("");
-		urlStream << "http://" << SERVER << "/Browse/Comments.json?ID=" << saveID << "&Start=" << (commentsPageNumber-1)*20 << "&Count=20";
-		commentsDownload = new Download(urlStream.str());
-		commentsDownload->AuthHeaders(format::NumberToByteString(Client::Ref().GetAuthUser().UserID), Client::Ref().GetAuthUser().SessionID);
+		url = ByteString::Build("http://", SERVER, "/Browse/Comments.json?ID=", saveID, "&Start=", (commentsPageNumber-1)*20, "&Count=20");
+		commentsDownload = new Download(url);
+		commentsDownload->AuthHeaders(ByteString::Build(Client::Ref().GetAuthUser().UserID), Client::Ref().GetAuthUser().SessionID);
 		commentsDownload->Start();
 	}
 }
@@ -143,10 +141,9 @@ void PreviewModel::UpdateComments(int pageNumber)
 		commentsPageNumber = pageNumber;
 		if (!GetDoOpen())
 		{
-			ByteString::Stream urlStream;
-			urlStream << "http://" << SERVER << "/Browse/Comments.json?ID=" << saveID << "&Start=" << (commentsPageNumber-1)*20 << "&Count=20";
-			commentsDownload = new Download(urlStream.str());
-			commentsDownload->AuthHeaders(format::NumberToByteString(Client::Ref().GetAuthUser().UserID), Client::Ref().GetAuthUser().SessionID);
+			ByteString url = ByteString::Build("http://", SERVER, "/Browse/Comments.json?ID=", saveID, "&Start=", (commentsPageNumber-1)*20, "&Count=20");
+			commentsDownload = new Download(url);
+			commentsDownload->AuthHeaders(ByteString::Build(Client::Ref().GetAuthUser().UserID), Client::Ref().GetAuthUser().SessionID);
 			commentsDownload->Start();
 		}
 
@@ -242,9 +239,7 @@ bool PreviewModel::ParseSaveInfo(char * saveInfoResponse)
 				saveDataDownload->Cancel();
 			delete saveData;
 			saveData = NULL;
-			ByteString::Stream urlStream;
-			urlStream << "http://" << STATICSERVER << "/2157797.cps";
-			saveDataDownload = new Download(urlStream.str());
+			saveDataDownload = new Download(ByteString::Build("http://", STATICSERVER, "/2157797.cps"));
 			saveDataDownload->Start();
 		}
 		return true;
@@ -268,7 +263,7 @@ bool PreviewModel::ParseComments(char *commentsResponse)
 
 		for (Json::UInt j = 0; j < commentsArray.size(); j++)
 		{
-			int userID = format::ByteStringToNumber<int>(commentsArray[j]["UserID"].asString());
+			int userID = ByteString(commentsArray[j]["UserID"].asString()).ToNumber<int>();
 			ByteString username = commentsArray[j]["Username"].asString();
 			ByteString formattedUsername = commentsArray[j]["FormattedUsername"].asString();
 			if (formattedUsername == "jacobot")
diff --git a/src/gui/preview/PreviewView.cpp b/src/gui/preview/PreviewView.cpp
index d1565471b..05140c921 100644
--- a/src/gui/preview/PreviewView.cpp
+++ b/src/gui/preview/PreviewView.cpp
@@ -227,11 +227,11 @@ void PreviewView::AttachController(PreviewController * controller)
 	saveIDLabel->Appearance.HorizontalAlign = ui::Appearance::AlignCentre;
 	AddComponent(saveIDLabel);
 
-	textWidth = Graphics::textwidth(format::NumberToString<int>(c->SaveID()).c_str());
+	textWidth = Graphics::textwidth(String::Build(c->SaveID()));
 	saveIDLabel2 = new ui::Label(ui::Point((Size.X-textWidth-20)/2-37, Size.Y+22), ui::Point(40, 16), "Save ID:");
 	AddComponent(saveIDLabel2);
 
-	saveIDButton = new ui::CopyTextButton(ui::Point((Size.X-textWidth-10)/2, Size.Y+20), ui::Point(textWidth+10, 18), format::NumberToString<int>(c->SaveID()), saveIDLabel);
+	saveIDButton = new ui::CopyTextButton(ui::Point((Size.X-textWidth-10)/2, Size.Y+20), ui::Point(textWidth+10, 18), String::Build(c->SaveID()), saveIDLabel);
 	AddComponent(saveIDButton);
 }
 
@@ -514,7 +514,7 @@ void PreviewView::NotifySaveChanged(PreviewModel * sender)
 			userIsAuthor = true;
 		else
 			userIsAuthor = false;
-		viewsLabel->SetText("\bgViews:\bw " + format::NumberToString<int>(save->Views));
+		viewsLabel->SetText(String::Build("\bgViews:\bw ", save->Views));
 		saveDescriptionLabel->SetText(save->Description);
 		if(save->Favourite)
 		{
diff --git a/src/gui/profile/ProfileActivity.cpp b/src/gui/profile/ProfileActivity.cpp
index e012e833a..7e9ee0644 100644
--- a/src/gui/profile/ProfileActivity.cpp
+++ b/src/gui/profile/ProfileActivity.cpp
@@ -122,7 +122,7 @@ void ProfileActivity::setUserInfo(UserInfo newInfo)
 	scrollPanel->AddChild(ageTitle);
 
 	// can't figure out how to tell a null from a 0 in the json library we use
-	ui::Label *age = new ui::Label(ui::Point(8+ageTitle->Size.X, currentY), ui::Point(40, 15), info.age ? format::NumberToString<int>(info.age) : "\bgNot Provided");
+	ui::Label *age = new ui::Label(ui::Point(8+ageTitle->Size.X, currentY), ui::Point(40, 15), info.age ? String::Build(info.age) : "\bgNot Provided");
 	age->Appearance.HorizontalAlign = ui::Appearance::AlignLeft;
 	scrollPanel->AddChild(age);
 	currentY += 2+age->Size.Y;
@@ -165,7 +165,7 @@ void ProfileActivity::setUserInfo(UserInfo newInfo)
 		saveCountTitle->SetTextColour(ui::Colour(180, 180, 180));
 		scrollPanel->AddChild(saveCountTitle);
 
-		ui::Label *savesCount = new ui::Label(ui::Point(12+saveCountTitle->Size.X, currentY), ui::Point(Size.X-saveCountTitle->Size.X-16, 15), format::NumberToString<int>(info.saveCount));
+		ui::Label *savesCount = new ui::Label(ui::Point(12+saveCountTitle->Size.X, currentY), ui::Point(Size.X-saveCountTitle->Size.X-16, 15), String::Build(info.saveCount));
 		savesCount->Appearance.HorizontalAlign = ui::Appearance::AlignLeft;
 		scrollPanel->AddChild(savesCount);
 		currentY += savesCount->Size.Y;
@@ -176,7 +176,7 @@ void ProfileActivity::setUserInfo(UserInfo newInfo)
 		averageScoreTitle->SetTextColour(ui::Colour(180, 180, 180));
 		scrollPanel->AddChild(averageScoreTitle);
 
-		ui::Label *averageScore = new ui::Label(ui::Point(12+averageScoreTitle->Size.X, currentY), ui::Point(Size.X-averageScoreTitle->Size.X-16, 15), format::NumberToString<float>(info.averageScore));
+		ui::Label *averageScore = new ui::Label(ui::Point(12+averageScoreTitle->Size.X, currentY), ui::Point(Size.X-averageScoreTitle->Size.X-16, 15), String::Build(info.averageScore));
 		averageScore->Appearance.HorizontalAlign = ui::Appearance::AlignLeft;
 		scrollPanel->AddChild(averageScore);
 		currentY += averageScore->Size.Y;
@@ -187,7 +187,7 @@ void ProfileActivity::setUserInfo(UserInfo newInfo)
 		highestScoreTitle->SetTextColour(ui::Colour(180, 180, 180));
 		scrollPanel->AddChild(highestScoreTitle);
 
-		ui::Label *highestScore = new ui::Label(ui::Point(12+highestScoreTitle->Size.X, currentY), ui::Point(Size.X-highestScoreTitle->Size.X-16, 15), format::NumberToString<int>(info.highestScore));
+		ui::Label *highestScore = new ui::Label(ui::Point(12+highestScoreTitle->Size.X, currentY), ui::Point(Size.X-highestScoreTitle->Size.X-16, 15), String::Build(info.highestScore));
 		highestScore->Appearance.HorizontalAlign = ui::Appearance::AlignLeft;
 		scrollPanel->AddChild(highestScore);
 		currentY += 2+highestScore->Size.Y;
diff --git a/src/gui/search/SearchView.cpp b/src/gui/search/SearchView.cpp
index 14fe3798f..e37658e2f 100644
--- a/src/gui/search/SearchView.cpp
+++ b/src/gui/search/SearchView.cpp
@@ -270,11 +270,11 @@ void SearchView::clearSearch()
 
 void SearchView::textChanged()
 {
-	int num = format::StringToNumber<int>(pageTextbox->GetText());
+	int num = pageTextbox->GetText().ToNumber<int>(true);
 	if (num < 0) //0 is allowed so that you can backspace the 1
 		pageTextbox->SetText("1");
 	else if (num > pageCount)
-		pageTextbox->SetText(format::NumberToString(pageCount));
+		pageTextbox->SetText(String::Build(pageCount));
 	changed = true;
 #ifdef USE_SDL
 	lastChanged = GetTicks()+600;
@@ -763,7 +763,7 @@ void SearchView::OnTick(float dt)
 	if (changed && lastChanged < GetTicks())
 	{
 		changed = false;
-		c->SetPage(std::max(format::StringToNumber<int>(pageTextbox->GetText()), 0));
+		c->SetPage(std::max(pageTextbox->GetText().ToNumber<int>(true), 0));
 	}
 #endif
 }
diff --git a/src/gui/update/UpdateActivity.cpp b/src/gui/update/UpdateActivity.cpp
index 3f9ddcb8b..03877c07d 100644
--- a/src/gui/update/UpdateActivity.cpp
+++ b/src/gui/update/UpdateActivity.cpp
@@ -116,13 +116,13 @@ private:
 };
 
 UpdateActivity::UpdateActivity() {
-	ByteString::Stream file;
+	ByteString file;
 #ifdef UPDATESERVER
-	file << "http://" << UPDATESERVER << Client::Ref().GetUpdateInfo().File;
+	file = ByteString::Build("http://", UPDATESERVER, Client::Ref().GetUpdateInfo().File);
 #else
-	file << "http://" << SERVER << Client::Ref().GetUpdateInfo().File;
+	file = ByteString::Build("http://", SERVER, Client::Ref().GetUpdateInfo().File);
 #endif
-	updateDownloadTask = new UpdateDownloadTask(file.str(), this);
+	updateDownloadTask = new UpdateDownloadTask(file, this);
 	updateWindow = new TaskWindow("Downloading update...", updateDownloadTask, true);
 }
 
diff --git a/src/lua/LegacyLuaAPI.cpp b/src/lua/LegacyLuaAPI.cpp
index b72c5a6d5..e24e33dcd 100644
--- a/src/lua/LegacyLuaAPI.cpp
+++ b/src/lua/LegacyLuaAPI.cpp
@@ -1914,13 +1914,12 @@ int luatpt_getscript(lua_State* l)
 	int runScript = luaL_optint(l, 3, 0);
 	int confirmPrompt = luaL_optint(l, 4, 1);
 
-	ByteString::Stream url;
-	url << "http://starcatcher.us/scripts/main.lua?get=" << scriptID;
-	if (confirmPrompt && !ConfirmPrompt::Blocking("Do you want to install script?", ByteString(url.str()).FromUtf8(), "Install"))
+	ByteString url = ByteString::Build("http://starcatcher.us/scripts/main.lua?get=", scriptID);
+	if (confirmPrompt && !ConfirmPrompt::Blocking("Do you want to install script?", url.FromUtf8(), "Install"))
 		return 0;
 
 	int ret, len;
-	char *scriptData = http_simple_get(url.str().c_str(), &ret, &len);
+	char *scriptData = http_simple_get(url.c_str(), &ret, &len);
 	if (len <= 0 || !filename)
 	{
 		free(scriptData);
@@ -1968,9 +1967,7 @@ int luatpt_getscript(lua_State* l)
 	outputfile = NULL;
 	if (runScript)
 	{
-		ByteString::Stream luaCommand;
-		luaCommand << "dofile('" << filename << "')";
-		luaL_dostring(l, luaCommand.str().c_str());
+		luaL_dostring(l, ByteString::Build("dofile('", filename, "')").c_str());
 	}
 
 	return 0;
@@ -2018,18 +2015,16 @@ int luatpt_screenshot(lua_State* l)
 			data = format::VideoBufferToPNG(screenshot);
 		}
 	}
-	ByteString::Stream filename;
-	filename << "screenshot_";
-	filename << std::setfill('0') << std::setw(6) << (screenshotIndex++);
+	ByteString filename = ByteString::Build("screenshot_", Format::Width(screenshotIndex++, 6));
 	if(fileType == 1) {
-		filename << ".bmp";
+		filename += ".bmp";
 	} else if(fileType == 2) {
-		filename << ".ppm";
+		filename += ".ppm";
 	} else {
-		filename << ".png";
+		filename += ".png";
 	}
-	Client::Ref().WriteFile(data, filename.str());
-	lua_pushstring(l, filename.str().c_str());
+	Client::Ref().WriteFile(data, filename);
+	lua_pushstring(l, filename.c_str());
 	return 1;
 }