diff --git a/index.js b/index.js
index a4ffdaa..cb7009e 100644
--- a/index.js
+++ b/index.js
@@ -2,7 +2,7 @@
 
 var gutil = require('gulp-util');
 var through = require('through2');
-var assign = require('object-assign');
+var clonedeep = require('lodash.clonedeep');
 var path = require('path');
 var applySourceMap = require('vinyl-sourcemaps-apply');
 
@@ -34,7 +34,7 @@ var gulpSass = function gulpSass(options, sync) {
     }
 
 
-    opts = assign({}, options);
+    opts = clonedeep(options || {});
     opts.data = file.contents.toString();
 
     // we set the file path here so that libsass can correctly resolve import paths
diff --git a/package.json b/package.json
index 1ae912e..ee07c5c 100644
--- a/package.json
+++ b/package.json
@@ -22,8 +22,8 @@
   },
   "dependencies": {
     "gulp-util": "^3.0",
+    "lodash.clonedeep": "^4.3.2",
     "node-sass": "^3.4.2",
-    "object-assign": "^4.0.1",
     "through2": "^2.0.0",
     "vinyl-sourcemaps-apply": "^0.2.0"
   },