diff --git a/src/s3_plugin.js b/src/s3_plugin.js
index 46f6c4cc..5c630192 100644
--- a/src/s3_plugin.js
+++ b/src/s3_plugin.js
@@ -102,22 +102,22 @@ module.exports = class S3Plugin {
         let dPath = addSeperatorToPath(this.options.directory)
 
         this.getAllFilesRecursive(dPath)
-          .then((files) => this.handleFiles(files, cb))
+          .then((files) => this.handleFiles(files, compilation))
           .then(() => cb())
           .catch(e => this.handleErrors(e, compilation, cb))
       } else {
         this.getAssetFiles(compilation)
-          .then((files) => this.handleFiles(files))
+          .then((files) => this.handleFiles(files, compilation))
           .then(() => cb())
           .catch(e => this.handleErrors(e, compilation, cb))
       }
     })
   }
 
-  handleFiles(files) {
+  handleFiles(files, compilation) {
     return this.changeUrls(files)
       .then((files) => this.filterAllowedFiles(files))
-      .then((files) => this.uploadFiles(files))
+      .then((files) => this.uploadFiles(files, compilation))
       .then(() => this.invalidateCloudfront())
   }
 
@@ -229,8 +229,8 @@ module.exports = class S3Plugin {
     this.isConnected = true
   }
 
-  transformBasePath() {
-    return Promise.resolve(this.basePathTransform(this.options.basePath))
+  transformBasePath(compilation) {
+    return Promise.resolve(this.basePathTransform(this.options.basePath, compilation))
       .then(addTrailingS3Sep)
       .then(nPath => this.options.basePath = nPath)
   }
@@ -268,8 +268,8 @@ module.exports = class S3Plugin {
     })
   }
 
-  uploadFiles(files = []) {
-    return this.transformBasePath()
+  uploadFiles(files = [], compilation) {
+    return this.transformBasePath(compilation)
       .then(() => {
         var uploadFiles = files.map(file => this.uploadFile(file.name, file.path))
 
diff --git a/test/upload_test.js b/test/upload_test.js
index eff106e5..f7d9b291 100644
--- a/test/upload_test.js
+++ b/test/upload_test.js
@@ -94,7 +94,10 @@ describe('S3 Webpack Upload', function() {
           BASE_PATH = 'test'
       var s3Config = {
         basePath: BASE_PATH,
-        basePathTransform(basePath) {
+        basePathTransform(basePath, compilation) {
+          assert.isString(basePath);
+          assert.isObject(compilation);
+
           return Promise.resolve(basePath + NAME_PREFIX)
         }
       }
@@ -117,7 +120,10 @@ describe('S3 Webpack Upload', function() {
           BASE_PATH = 'test'
       var s3Config = {
         basePath: BASE_PATH,
-        basePathTransform(basePath) {
+        basePathTransform(basePath, compilation) {
+          assert.isString(basePath);
+          assert.isObject(compilation);
+
           return basePath + NAME_PREFIX
         }
       }