diff --git a/ext/native/net/websocket_server.cpp b/ext/native/net/websocket_server.cpp
index ce9af81fc0..2c7ec1cd54 100644
--- a/ext/native/net/websocket_server.cpp
+++ b/ext/native/net/websocket_server.cpp
@@ -130,24 +130,14 @@ void WebSocketServer::Send(const std::string &str) {
 	assert(open_);
 	assert(fragmentOpcode_ == -1);
 	SendHeader(true, (int)Opcode::TEXT, str.size());
-	// TODO: For long strings, this will block.  Possibly not ideal.
-	if (!out_->Push(str.c_str(), str.size())) {
-		assert(false);
-		open_ = false;
-		closeReason_ = WebSocketClose::ABNORMAL;
-	}
+	SendBytes(str.c_str(), str.size());
 }
 
 void WebSocketServer::Send(const std::vector<uint8_t> &payload) {
 	assert(open_);
 	assert(fragmentOpcode_ == -1);
 	SendHeader(true, (int)Opcode::BINARY, payload.size());
-	// TODO: For long strings, this will block.  Possibly not ideal.
-	if (!out_->Push((const char *)&payload[0], payload.size())) {
-		assert(false);
-		open_ = false;
-		closeReason_ = WebSocketClose::ABNORMAL;
-	}
+	SendBytes((const char *)&payload[0], payload.size());
 }
 
 void WebSocketServer::AddFragment(bool finish, const std::string &str) {
@@ -160,12 +150,7 @@ void WebSocketServer::AddFragment(bool finish, const std::string &str) {
 	} else {
 		assert(fragmentOpcode_ == (int)Opcode::TEXT || fragmentOpcode_ == -1);
 	}
-	// TODO: For long strings, this will block.  Possibly not ideal.
-	if (!out_->Push(str.c_str(), str.size())) {
-		assert(false);
-		open_ = false;
-		closeReason_ = WebSocketClose::ABNORMAL;
-	}
+	SendBytes(str.c_str(), str.size());
 	if (finish) {
 		fragmentOpcode_ = -1;
 	}
@@ -181,12 +166,7 @@ void WebSocketServer::AddFragment(bool finish, const std::vector<uint8_t> &paylo
 	} else {
 		assert(fragmentOpcode_ == (int)Opcode::BINARY || fragmentOpcode_ == -1);
 	}
-	// TODO: For long strings, this will block.  Possibly not ideal.
-	if (!out_->Push((const char *)&payload[0], payload.size())) {
-		assert(false);
-		open_ = false;
-		closeReason_ = WebSocketClose::ABNORMAL;
-	}
+	SendBytes((const char *)&payload[0], payload.size());
 	if (finish) {
 		fragmentOpcode_ = -1;
 	}
@@ -196,22 +176,14 @@ void WebSocketServer::Ping(const std::vector<uint8_t> &payload) {
 	assert(open_);
 	assert(payload.size() <= 125);
 	SendHeader(true, (int)Opcode::PING, payload.size());
-	if (!out_->Push((const char *)&payload[0], payload.size())) {
-		assert(false);
-		open_ = false;
-		closeReason_ = WebSocketClose::ABNORMAL;
-	}
+	SendBytes((const char *)&payload[0], payload.size());
 }
 
 void WebSocketServer::Pong(const std::vector<uint8_t> &payload) {
 	assert(open_);
 	assert(payload.size() <= 125);
 	SendHeader(true, (int)Opcode::PONG, payload.size());
-	if (!out_->Push((const char *)&payload[0], payload.size())) {
-		assert(false);
-		open_ = false;
-		closeReason_ = WebSocketClose::ABNORMAL;
-	}
+	SendBytes((const char *)&payload[0], payload.size());
 }
 
 void WebSocketServer::Close(WebSocketClose reason) {
@@ -223,11 +195,7 @@ void WebSocketServer::Close(WebSocketClose reason) {
 		(uint8_t)((r >> 8) & 0xFF),
 		(uint8_t)((r >> 0) & 0xFF),
 	};
-	if (!out_->Push((const char *)reasonData, sizeof(reasonData))) {
-		assert(false);
-		open_ = false;
-		closeReason_ = WebSocketClose::ABNORMAL;
-	}
+	SendBytes((const char *)reasonData, sizeof(reasonData));
 
 	sentClose_ = true;
 }
@@ -237,9 +205,9 @@ bool WebSocketServer::Process(float timeout) {
 		return false;
 	}
 
-	out_->Flush(false);
+	SendFlush();
 
-	if (out_->Empty() && sentClose_) {
+	if (outBuf_.empty() && out_->Empty() && sentClose_) {
 		// Okay, we've sent the close.  Don't wait for anything else (whether we got a close or not.)
 		open_ = false;
 		return false;
@@ -258,7 +226,7 @@ bool WebSocketServer::Process(float timeout) {
 
 	fd_set write;
 	FD_ZERO(&write);
-	if (!out_->Empty()) {
+	if (!outBuf_.empty() || !out_->Empty()) {
 		FD_SET(fd_, &write);
 	}
 
@@ -276,7 +244,7 @@ bool WebSocketServer::Process(float timeout) {
 	}
 
 	if (FD_ISSET(fd_, &write)) {
-		out_->Flush(false);
+		SendFlush();
 	}
 	if (FD_ISSET(fd_, &read)) {
 		if (in_->Empty() && !in_->TryFill()) {
@@ -462,7 +430,7 @@ bool WebSocketServer::ReadControlFrame(int opcode, size_t sz) {
 	if (opcode == (int)Opcode::PING) {
 		Pong(payload);
 		// Try to send immediately if possible, but don't block.
-		out_->Flush(false);
+		SendFlush();
 
 		if (ping_) {
 			ping_(payload);
@@ -491,19 +459,19 @@ bool WebSocketServer::ReadControlFrame(int opcode, size_t sz) {
 void WebSocketServer::SendHeader(bool fin, int opcode, size_t sz) {
 	assert((opcode & 0x0F) == opcode);
 	uint8_t frameHeader = (fin ? 0x80 : 0x00) | opcode;
-	out_->Push((const char *)&frameHeader, 1);
+	SendBytes(&frameHeader, 1);
 
 	// We never mask from the server.
 	if (sz <= 125) {
 		uint8_t frameSize = (int8_t)sz;
-		out_->Push((const char *)&frameSize, 1);
+		SendBytes(&frameSize, 1);
 	} else if (sz <= 0xFFFF) {
 		uint8_t frameSize[] = {
 			126,
 			(uint8_t)((sz >> 8) & 0xFF),
 			(uint8_t)((sz >> 0) & 0xFF),
 		};
-		out_->Push((const char *)frameSize, sizeof(frameSize));
+		SendBytes(frameSize, sizeof(frameSize));
 	} else {
 		uint64_t sz64 = sz;
 		assert((sz64 & 0x8000000000000000ULL) == 0);
@@ -518,7 +486,42 @@ void WebSocketServer::SendHeader(bool fin, int opcode, size_t sz) {
 			(uint8_t)((sz64 >> 8) & 0xFF),
 			(uint8_t)((sz64 >> 0) & 0xFF),
 		};
-		out_->Push((const char *)frameSize, sizeof(frameSize));
+		SendBytes(frameSize, sizeof(frameSize));
+	}
+}
+
+void WebSocketServer::SendBytes(const void *p, size_t sz) {
+	const char *data = (const char *)p;
+	if (outBuf_.empty()) {
+		size_t pushed = out_->PushAtMost(data, sz);
+		data += pushed;
+		sz -= pushed;
+	}
+
+	if (sz != 0) {
+		size_t pos = outBuf_.size();
+		outBuf_.resize(pos + sz);
+		memcpy(&outBuf_[pos], data, sz);
+	}
+}
+
+void WebSocketServer::SendFlush() {
+	out_->Flush(false);
+
+	// Drain out as much of our buffer as possible.
+	size_t totalPushed = 0;
+	while (!outBuf_.empty()) {
+		size_t pushed = out_->PushAtMost((const char *)&outBuf_[totalPushed], outBuf_.size() - totalPushed);
+		if (pushed == 0)
+			break;
+
+		totalPushed += pushed;
+		out_->Flush(false);
+	}
+
+	if (totalPushed != 0) {
+		// Hopefully this is usually the entire buffer.
+		outBuf_.erase(outBuf_.begin(), outBuf_.begin() + totalPushed);
 	}
 }
 
diff --git a/ext/native/net/websocket_server.h b/ext/native/net/websocket_server.h
index edd753fed6..98426f53cf 100644
--- a/ext/native/net/websocket_server.h
+++ b/ext/native/net/websocket_server.h
@@ -71,6 +71,8 @@ protected:
 	}
 
 	void SendHeader(bool fin, int opcode, size_t sz);
+	void SendBytes(const void *p, size_t sz);
+	void SendFlush();
 	bool ReadFrames();
 	bool ReadFrame();
 	bool ReadPending();
@@ -83,6 +85,7 @@ protected:
 	InputSink *in_ = nullptr;
 	OutputSink *out_ = nullptr;
 	WebSocketClose closeReason_ = WebSocketClose::NO_STATUS;
+	std::vector<uint8_t> outBuf_;
 
 	std::vector<uint8_t> pendingBuf_;
 	uint8_t pendingMask_[4]{};