diff --git a/backend/src/schema/resolvers/registration.spec.js b/backend/src/schema/resolvers/registration.spec.js
index 63dc35519..ea618b32e 100644
--- a/backend/src/schema/resolvers/registration.spec.js
+++ b/backend/src/schema/resolvers/registration.spec.js
@@ -15,7 +15,8 @@ beforeEach(async () => {
   variables = {}
 })
 
-beforeAll(() => {
+beforeAll(async () => {
+  await cleanDatabase()
   const { server } = createServer({
     context: () => {
       return {
@@ -34,8 +35,8 @@ afterEach(async () => {
 
 describe('Signup', () => {
   const mutation = gql`
-    mutation($email: String!) {
-      Signup(email: $email) {
+    mutation($email: String!, $inviteCode: String) {
+      Signup(email: $email, inviteCode: $inviteCode) {
         email
       }
     }
diff --git a/backend/src/schema/types/type/EmailAddress.gql b/backend/src/schema/types/type/EmailAddress.gql
index 3808d1937..ef9de9e47 100644
--- a/backend/src/schema/types/type/EmailAddress.gql
+++ b/backend/src/schema/types/type/EmailAddress.gql
@@ -9,7 +9,7 @@ type Query {
 }
 
 type Mutation {
-  Signup(email: String!, inviteCode: String): EmailAddress
+  Signup(email: String!, inviteCode: String = null): EmailAddress
   SignupVerification(
     nonce: String!
     email: String!