diff --git a/package.json b/package.json
index 44b543f4..6f0da454 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "widgetizer-widgetizer",
-  "version": "0.3.4",
+  "version": "0.3.5",
   "description": "Production-ready Node.js GraphQL server for Express, HAPI, Koa",
   "main": "dist/index.js",
   "directories": {
diff --git a/src/core/runQuery.test.ts b/src/core/runQuery.test.ts
index f87e619e..85638df1 100644
--- a/src/core/runQuery.test.ts
+++ b/src/core/runQuery.test.ts
@@ -141,20 +141,32 @@ describe('runQuery', () => {
       });
   });
 
+  it('throws a validation error if there are missing variables', () => {
+      const query = `query TestVar($base: Int!){ testArgumentValue(base: $base) }`;
+      const expected = 'Variable "$base" of required type "Int!" was not provided.';
+      return runQuery({
+          schema: Schema,
+          query: query,
+      }).then((res) => {
+          return expect(res.errors[0].message).to.deep.equal(expected);
+      });
+  });
+
+
     it('runs the correct operation when operationName is specified', () => {
-      const query = `
+        const query = `
         query Q1 {
             testString
         }
         query Q2 {
             testRootValue
         }`;
-      const expected = {
-          testString: 'it works',
+        const expected = {
+            testString: 'it works',
         };
-      return runQuery({ schema: Schema, query: query, operationName: 'Q1' })
-      .then((res) => {
-          return expect(res.data).to.deep.equal(expected);
-      });
-  });
+        return runQuery({ schema: Schema, query: query, operationName: 'Q1' })
+        .then((res) => {
+            return expect(res.data).to.deep.equal(expected);
+        });
+    });
 });
diff --git a/src/core/runQuery.ts b/src/core/runQuery.ts
index 9f710ede..d229a737 100644
--- a/src/core/runQuery.ts
+++ b/src/core/runQuery.ts
@@ -19,6 +19,8 @@ export interface GqlResponse {
     errors?: Array<string>;
 }
 
+import { Promise } from 'es6-promise';
+
 export interface QueryOptions {
  schema: GraphQLSchema;
  query: string | Document;
diff --git a/src/integrations/expressApollo.test.ts b/src/integrations/expressApollo.test.ts
index 10ba39e0..f02b9f3d 100644
--- a/src/integrations/expressApollo.test.ts
+++ b/src/integrations/expressApollo.test.ts
@@ -104,6 +104,25 @@ describe('expressApollo', () => {
         });
     });
 
+    it('can handle a request with variables as string', () => {
+        const app = express();
+        app.use('/graphql', bodyParser.json());
+        app.use('/graphql', graphqlHTTP({ schema: Schema }));
+        const expected = {
+            testArgument: 'hello world',
+        };
+        const req = request(app)
+            .post('/graphql')
+            .send({
+                query: 'query test($echo: String!){ testArgument(echo: $echo) }',
+                variables: '{ "echo": "world" }',
+            });
+        req.then((res) => {
+            expect(res.status).to.equal(200);
+            return expect(res.body.data).to.deep.equal(expected);
+        });
+    });
+
     it('can handle a request with operationName', () => {
         const app = express();
         app.use('/graphql', bodyParser.json());
diff --git a/src/integrations/expressApollo.ts b/src/integrations/expressApollo.ts
index e3a2999e..bfa2962a 100644
--- a/src/integrations/expressApollo.ts
+++ b/src/integrations/expressApollo.ts
@@ -55,7 +55,12 @@ export function graphqlHTTP(options: ExpressApolloOptions | ExpressApolloOptions
     }
 
     // TODO: some sanity checks here.
-    const { query, variables, operationName } = req.body;
+    let { query, variables, operationName } = req.body;
+
+    if (typeof variables === 'string') {
+      // TODO: catch errors
+      variables = JSON.parse(variables);
+    }
 
     // either query or operationName must be present. Return 400 otherwise
     // if only operationName is present, check if it's in store. Return 400 otherwise