gistfile1.txt

diff --git a/lib/zlib.js b/lib/zlib.js
index 43725bf..a5821e7 100644
--- a/lib/zlib.js
+++ b/lib/zlib.js
@@ -246,6 +246,8 @@ Zlib.prototype.end = function end(chunk, cb) {
   return ret;
 };
 
+var reqCache = {};
+
 Zlib.prototype._process = function() {
   if (this._processing || this._paused) return;
 
@@ -270,6 +272,7 @@ Zlib.prototype._process = function() {
   var availOutBefore = this._chunkSize - this._offset;
 
   var inOff = 0;
+
   var req = this._binding.write(this._flush,
                                 chunk, // in
                                 inOff, // in_off
@@ -282,7 +285,12 @@ Zlib.prototype._process = function() {
   req.callback = callback;
   this._processing = req;
 
+  var reqId = req.id = Math.random();
+  reqCache[reqId] = req;
+
   function callback(availInAfter, availOutAfter, buffer) {
+    reqCache[reqId] = null;
+
     var have = availOutBefore - availOutAfter;
 
     assert(have >= 0, 'have should not go down');