diff --git a/npm-shrinkwrap.json b/npm-shrinkwrap.json
index a0e0b4099..b9de79933 100644
--- a/npm-shrinkwrap.json
+++ b/npm-shrinkwrap.json
@@ -4495,9 +4495,9 @@
       "optional": true
     },
     "safetydance": {
-      "version": "0.4.0",
-      "from": "safetydance@0.4.0",
-      "resolved": "https://registry.npmjs.org/safetydance/-/safetydance-0.4.0.tgz"
+      "version": "0.6.0",
+      "from": "safetydance@0.6.0",
+      "resolved": "https://registry.npmjs.org/safetydance/-/safetydance-0.6.0.tgz"
     },
     "sass-graph": {
       "version": "2.2.4",
diff --git a/package.json b/package.json
index 2ef749baf..fc6fc3cc9 100644
--- a/package.json
+++ b/package.json
@@ -59,7 +59,7 @@
     "progress-stream": "^2.0.0",
     "proxy-middleware": "^0.13.0",
     "s3-block-read-stream": "^0.2.0",
-    "safetydance": "^0.4.0",
+    "safetydance": "^0.6.0",
     "semver": "^4.3.6",
     "showdown": "^1.6.0",
     "split": "^1.0.0",
diff --git a/src/backups.js b/src/backups.js
index 2a1a2d28d..07e3e6789 100644
--- a/src/backups.js
+++ b/src/backups.js
@@ -225,7 +225,11 @@ function sync(backupConfig, backupId, dataDir, callback) {
         } else if (task.operation === 'remove') {
             api(backupConfig.provider).remove(backupConfig, getBackupFilePath(backupConfig, backupId, task.path), iteratorCallback);
         }
-    }, callback);
+    }, function (error) {
+        if (error) return callback(new BackupsError(BackupsError.EXTERNAL_ERROR, error.message));
+
+        callback();
+    });
 }
 
 function saveEmptyDirs(appDataDir, callback) {
diff --git a/src/syncer.js b/src/syncer.js
index 359defd3b..9ab306db5 100644
--- a/src/syncer.js
+++ b/src/syncer.js
@@ -1,7 +1,7 @@
 'use strict';
 
 var assert = require('assert'),
-    fs = require('fs'),
+    debug = require('debug')('box:syncer'),
     path = require('path'),
     paths = require('./paths.js'),
     safe = require('safetydance');
@@ -15,7 +15,7 @@ function readCache(cacheFile) {
 
     var cache = safe.fs.readFileSync(cacheFile, 'utf8');
     if (!cache) return [ ];
-    var result = cache.split('\n').map(JSON.parse);
+    var result = cache.trim().split('\n').map(JSON.parse);
     return result;
 }
 
@@ -25,8 +25,7 @@ function readTree(dir) {
     var list = safe.fs.readdirSync(dir).sort();
     if (!list) return [ ];
 
-    // TODO: handle lstat errors
-    return list.map(function (e) { return { stat: fs.lstatSync(path.join(dir, e)), name: e }; });
+    return list.map(function (e) { return { stat: safe.fs.lstatSync(path.join(dir, e)), name: e }; });
 }
 
 // TODO: concurrency
@@ -42,7 +41,8 @@ function sync(dir, taskProcessor, callback) {
 
     var cache = readCache(cacheFile);
 
-    var newCacheFd = fs.openSync(newCacheFile, 'w'); // truncates any existing file
+    var newCacheFd = safe.fs.openSync(newCacheFile, 'w'); // truncates any existing file
+    if (newCacheFd === -1) return callback(new Error('Error opening new cache file: ' + safe.error.message));
 
     var dummyCallback = function() { };
 
@@ -59,6 +59,7 @@ function sync(dir, taskProcessor, callback) {
             var entryPath = path.join(relpath, entries[i].name);
             var stat = entries[i].stat;
 
+            if (!stat) continue; // some stat error
             if (!stat.isDirectory() && !stat.isFile()) continue;
             if (stat.isSymbolicLink()) continue;
 
@@ -67,7 +68,7 @@ function sync(dir, taskProcessor, callback) {
                 continue;
             }
 
-            fs.appendFileSync(newCacheFd, JSON.stringify({ path: entryPath, mtime: stat.mtime.getTime()  }) + '\n');
+            safe.fs.appendFileSync(newCacheFd, JSON.stringify({ path: entryPath, mtime: stat.mtime.getTime()  }) + '\n');
 
             advanceCache(entryPath);
 
@@ -83,12 +84,13 @@ function sync(dir, taskProcessor, callback) {
     }
 
     traverse('');
-    advanceCache('');               // remove rest of the cache entries
+    advanceCache(''); // remove rest of the cache entries
 
     // move the new cache file
-    fs.closeSync(newCacheFd);
-    fs.unlinkSync(cacheFile);
-    fs.renameSync(cacheFile, newCacheFd);
+    safe.fs.closeSync(newCacheFd);
+    safe.fs.unlinkSync(cacheFile);
+
+    if (!safe.fs.renameSync(newCacheFile, cacheFile)) debug('Unable to save new cache file');
 
     callback();
 }
\ No newline at end of file