diff --git a/libs/fs.js b/libs/fs.js
index 03655dc42..82fe230e3 100644
--- a/libs/fs.js
+++ b/libs/fs.js
@@ -32,12 +32,14 @@ var fs = (function() {
       window.setZeroTimeout(function() { cb(value) });
     } else {
       var transaction = this.db.transaction(Store.DBSTORENAME, "readonly");
+      if (DEBUG_FS) { console.log("get " + key + " initiated"); }
       var objectStore = transaction.objectStore(Store.DBSTORENAME);
       var req = objectStore.get(key);
       req.onerror = function() {
         console.error("Error getting " + key + ": " + req.error.name);
       };
       transaction.oncomplete = (function() {
+        if (DEBUG_FS) { console.log("get " + key + " completed"); }
         var value = req.result;
         if (value === undefined) {
           value = null;
@@ -52,33 +54,60 @@ var fs = (function() {
     this.map.set(key, value);
 
     var transaction = this.db.transaction(Store.DBSTORENAME, "readwrite");
+    if (DEBUG_FS) { console.log("put " + key + " initiated"); }
     var objectStore = transaction.objectStore(Store.DBSTORENAME);
     var req = objectStore.put(value, key);
     req.onerror = function() {
       console.error("Error putting " + key + ": " + req.error.name);
     };
+    transaction.oncomplete = function() {
+      if (DEBUG_FS) { console.log("put " + key + " completed"); }
+    };
   };
 
   Store.prototype.removeItem = function(key) {
     this.map.delete(key);
 
     var transaction = this.db.transaction(Store.DBSTORENAME, "readwrite");
+    if (DEBUG_FS) { console.log("delete " + key + " initiated"); }
     var objectStore = transaction.objectStore(Store.DBSTORENAME);
     var req = objectStore.delete(key);
     req.onerror = function() {
       console.error("Error deleting " + key + ": " + req.error.name);
     };
+    transaction.oncomplete = function() {
+      if (DEBUG_FS) { console.log("delete " + key + " completed"); }
+    };
   };
 
   Store.prototype.clear = function() {
     this.map.clear();
 
     var transaction = this.db.transaction(Store.DBSTORENAME, "readwrite");
+    if (DEBUG_FS) { console.log("clear initiated"); }
     var objectStore = transaction.objectStore(Store.DBSTORENAME);
     var req = objectStore.clear();
     req.onerror = function() {
       console.error("Error clearing store: " + req.error.name);
     };
+    transaction.oncomplete = function() {
+      if (DEBUG_FS) { console.log("clear completed"); }
+    };
+  }
+
+  Store.prototype.sync = function(cb) {
+    // Process a readwrite transaction to ensure previous writes have completed,
+    // so we leave the datastore in a consistent state.  This is a bit hacky;
+    // we should instead monitor ongoing transactions and call our callback
+    // once they've all completed.
+    var transaction = this.db.transaction(Store.DBSTORENAME, "readwrite");
+    if (DEBUG_FS) { console.log("get \"\" initiated"); }
+    var objectStore = transaction.objectStore(Store.DBSTORENAME);
+    objectStore.get("");
+    transaction.oncomplete = function() {
+      if (DEBUG_FS) { console.log("get \"\" completed"); }
+      cb();
+    };
   }
 
   var store = new Store();
@@ -560,6 +589,10 @@ var fs = (function() {
     initRootDir(cb || function() {});
   }
 
+  function storeSync(cb) {
+    store.sync(cb);
+  }
+
   return {
     dirname: dirname,
     init: init,
@@ -583,5 +616,6 @@ var fs = (function() {
     rename: rename,
     stat: stat,
     clear: clear,
+    storeSync: storeSync,
   };
 })();
diff --git a/tests/automation.js b/tests/automation.js
index 6cde78d1d..4a3de9340 100644
--- a/tests/automation.js
+++ b/tests/automation.js
@@ -102,7 +102,7 @@ casper.test.begin("unit tests", 7 + gfxTests.length, function(test) {
     casper
     .thenOpen("http://localhost:8000/tests/fstests.html")
     .waitForText("DONE", function() {
-        test.assertTextExists("DONE: 126 PASS, 0 FAIL", "run fs.js unit tests");
+        test.assertTextExists("DONE: 127 PASS, 0 FAIL", "run fs.js unit tests");
     });
 
     casper
diff --git a/tests/fstests.js b/tests/fstests.js
index 8a2aacf94..86c78c8f1 100644
--- a/tests/fstests.js
+++ b/tests/fstests.js
@@ -808,6 +808,16 @@ tests.push(function() {
   });
 });
 
+tests.push(function() {
+  fs.storeSync(function() {
+    // There's nothing we can check, since the sync status of the store
+    // is private to the fs module, but we have at least confirmed that the call
+    // resulted in the callback being called.
+    ok(true, "storeSync callback called");
+    next();
+  });
+});
+
 fs.init(function() {
   fs.clear(function() {
     next();