diff --git a/lib/byte_queue.js b/lib/byte_queue.js
new file mode 100644
index 00000000..d71d9e31
--- /dev/null
+++ b/lib/byte_queue.js
@@ -0,0 +1,111 @@
+// Efficient scatter-gather byte-stream queue
+// Copyright (C) 2020 Tirotech Ltd
+//
+// Author: Daniel Beer <daniel.beer@tirotech.co.nz>
+//
+// Permission to use, copy, modify, and/or distribute this software for any
+// purpose with or without fee is hereby granted, provided that the above
+// copyright notice and this permission notice appear in all copies.
+//
+// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+// ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+// ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+// OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+function fill(out, arr, j) {
+    while (out.length > 0 && j < arr.length) {
+	let b = arr[j];
+
+	b.copy(out);
+
+	if (b.length <= out.length) {
+	    out = out.slice(b.length);
+	    j++;
+	} else {
+	    out = out.slice(out.length);
+	}
+    }
+
+    return out;
+}
+
+function ByteQueue() {
+    this.front = [];
+    this.back = [];
+    this.i = 0;
+    this.len = 0;
+
+    return this;
+}
+
+ByteQueue.prototype = {
+    discard: function(n) {
+	while (this.i < this.front.length &&
+	       this.front[this.i].length <= n) {
+	    n -= this.front[this.i].length;
+	    this.len -= this.front[this.i].length;
+	    this.i++;
+	}
+
+	if (this.i >= this.front.length) {
+	    this.front = this.back;
+	    this.back = [];
+	    this.i = 0;
+	}
+
+	while (this.i < this.front.length &&
+	       this.front[this.i].length <= n) {
+	    n -= this.front[this.i].length;
+	    this.len -= this.front[this.i].length;
+	    this.i++;
+	}
+
+	if (n > 0) {
+	    if (this.i >= this.front.length ||
+		this.front[this.i].length < n)
+		throw "ByteQueue underrun";
+
+	    this.front[this.i] = this.front[this.i].slice(n);
+	    this.len -= n;
+	}
+    },
+
+    size: function() {
+	return this.len;
+    },
+
+    push: function(x) {
+	this.back.push(x);
+	this.len += x.length;
+    },
+
+    peekTo: function(buf) {
+	buf = fill(buf, this.front, this.i);
+	buf = fill(buf, this.back, 0);
+
+	if (buf.length > 0)
+	    throw "ByteQueue underrun";
+    },
+
+    peek: function(n) {
+	const buf = Buffer.alloc(n);
+	this.peekTo(buf);
+	return buf;
+    },
+
+    shiftTo: function(buf) {
+	this.peekTo(buf);
+	this.discard(buf.length);
+    },
+
+    shift: function(n) {
+	const buf = this.peek(n)
+	this.discard(n)
+	return buf
+    }
+}
+
+module.exports = { ByteQueue };
diff --git a/lib/connection.js b/lib/connection.js
index 0b9c727f..738961cc 100644
--- a/lib/connection.js
+++ b/lib/connection.js
@@ -5,6 +5,7 @@ const Backend = require('./backend.js')
 const Queue = require('./queue.js')
 const { END } = require('./types.js')
 const { errors } = require('./errors.js')
+const { ByteQueue } = require('./byte_queue.js');
 
 module.exports = Connection
 
@@ -21,7 +22,7 @@ function Connection(options = {}) {
     onclose,
     parsers
   } = options
-  let buffer = Buffer.alloc(0)
+  let buffer = new ByteQueue();
   let length = 0
   let messages = []
   let timer
@@ -255,17 +256,16 @@ function Connection(options = {}) {
   }
 
   function data(x) {
-    buffer = buffer.length === 0
-      ? x
-      : Buffer.concat([buffer, x], buffer.length + x.length)
+    buffer.push(x);
 
-    while (buffer.length > 4) {
-      length = buffer.readInt32BE(1)
-      if (length >= buffer.length)
-        break
+    while (buffer.size() > 4) {
+      const header = buffer.peek(5);
 
-      backend[buffer[0]](buffer.slice(0, length + 1))
-      buffer = buffer.slice(length + 1)
+      length = header.readInt32BE(1)
+      if (length >= buffer.size())
+	break
+
+      backend[header[0]](buffer.shift(length + 1))
     }
   }