diff --git a/package.json b/package.json
index 7fb91a65..56620159 100644
--- a/package.json
+++ b/package.json
@@ -25,6 +25,7 @@
     "lib": "./dist"
   },
   "files": [
+    "src",
     "dist",
     "README.md",
     "LICENSE",
@@ -40,6 +41,7 @@
     "lint": "eslint src",
     "check": "flow check",
     "build": "rm -rf dist/* && babel src --ignore __tests__ --out-dir dist",
+    "postinstall": "rm -rf dist/* && babel src --ignore __tests__ --out-dir dist",
     "watch": "babel --optional runtime resources/watch.js | node",
     "cover": "babel-node node_modules/.bin/isparta cover --root src --report html node_modules/.bin/_mocha -- $npm_package_options_mocha",
     "cover:lcov": "babel-node node_modules/.bin/isparta cover --root src --report lcovonly node_modules/.bin/_mocha -- $npm_package_options_mocha",
@@ -66,7 +68,7 @@
     "express": "4.13.3",
     "express3": "*",
     "flow-bin": "0.18.1",
-    "graphql": "0.4.8",
+    "graphql": "0.4.14",
     "isparta": "3.0.3",
     "mocha": "2.2.5",
     "multer": "1.0.3",
diff --git a/src/__tests__/http-test.js b/src/__tests__/http-test.js
index 31878dbf..97a1e149 100644
--- a/src/__tests__/http-test.js
+++ b/src/__tests__/http-test.js
@@ -793,6 +793,26 @@ describe('test harness', () => {
     });
 
     describe('Error handling functionality', () => {
+      it('call errorsCallback on errors', async done => {
+        var app = express();
+
+        app.use(urlString(), graphqlHTTP({
+          schema: TestSchema,
+          pretty: true
+        }, errors => {
+          expect(errors).to.have.length(1);
+          let error = errors[0];
+          expect(error.message).to.equal('Throws!');
+          expect(error.originalError).to.be.an('object');
+          done();
+        }));
+
+        await request(app)
+        .get(urlString({
+          query: '{thrower}',
+        }));
+      });
+
       it('handles field errors caught by GraphQL', async () => {
         var app = express();
 
diff --git a/src/index.js b/src/index.js
index 38258bc3..f7de37f0 100644
--- a/src/index.js
+++ b/src/index.js
@@ -51,7 +51,7 @@ type Middleware = (request: Request, response: Response) => void;
  * Middleware for express; takes an options object or function as input to
  * configure behavior, and returns an express middleware.
  */
-export default function graphqlHTTP(options: Options): Middleware {
+export default function graphqlHTTP(options: Options, errorsCallback: ?Function): Middleware {
   if (!options) {
     throw new Error('GraphQL middleware requires options.');
   }
@@ -169,8 +169,14 @@ export default function graphqlHTTP(options: Options): Middleware {
       response.status(error.status || 500);
       return { errors: [ error ] };
     }).then(result => {
+
       // Format any encountered errors.
       if (result && result.errors) {
+        // Call errorsCallback if errors
+        if (errorsCallback ) {
+          errorsCallback(result.errors);
+        }
+
         result.errors = result.errors.map(formatError);
       }