diff --git a/backend/src/middleware/filterBubble/filterBubble.spec.js b/backend/src/middleware/filterBubble/filterBubble.spec.js
index 62addeece..c71332db6 100644
--- a/backend/src/middleware/filterBubble/filterBubble.spec.js
+++ b/backend/src/middleware/filterBubble/filterBubble.spec.js
@@ -1,8 +1,10 @@
 import { GraphQLClient } from 'graphql-request'
 import { host, login } from '../../jest/helpers'
 import Factory from '../../seed/factories'
+import { neode } from '../../bootstrap/neo4j'
 
 const factory = Factory()
+const instance = neode()
 
 const currentUserParams = {
   id: 'u1',
@@ -21,6 +23,7 @@ const randomAuthorParams = {
   name: 'Someone else',
   password: 'else',
 }
+const categoryIds = ['cat9']
 
 beforeEach(async () => {
   await Promise.all([
@@ -28,14 +31,19 @@ beforeEach(async () => {
     factory.create('User', followedAuthorParams),
     factory.create('User', randomAuthorParams),
   ])
+  await instance.create('Category', {
+    id: 'cat9',
+    name: 'Democracy & Politics',
+    icon: 'university',
+  })
   const [asYourself, asFollowedUser, asSomeoneElse] = await Promise.all([
     Factory().authenticateAs(currentUserParams),
     Factory().authenticateAs(followedAuthorParams),
     Factory().authenticateAs(randomAuthorParams),
   ])
   await asYourself.follow({ id: 'u2', type: 'User' })
-  await asFollowedUser.create('Post', { title: 'This is the post of a followed user' })
-  await asSomeoneElse.create('Post', { title: 'This is some random post' })
+  await asFollowedUser.create('Post', { title: 'This is the post of a followed user', categoryIds })
+  await asSomeoneElse.create('Post', { title: 'This is some random post', categoryIds })
 })
 
 afterEach(async () => {
diff --git a/backend/src/middleware/handleHtmlContent/handleContentData.spec.js b/backend/src/middleware/handleHtmlContent/handleContentData.spec.js
index fb088e428..7f77b4589 100644
--- a/backend/src/middleware/handleHtmlContent/handleContentData.spec.js
+++ b/backend/src/middleware/handleHtmlContent/handleContentData.spec.js
@@ -4,14 +4,32 @@ import { createTestClient } from 'apollo-server-testing'
 import { neode, getDriver } from '../../bootstrap/neo4j'
 import createServer from '../../server'
 
-const factory = Factory()
-const driver = getDriver()
-const instance = neode()
 let server
 let query
 let mutate
 let user
 let authenticatedUser
+const factory = Factory()
+const driver = getDriver()
+const instance = neode()
+const categoryIds = ['cat9']
+const createPostMutation = gql`
+  mutation($id: ID, $title: String!, $content: String!, $categoryIds: [ID]!) {
+    CreatePost(id: $id, title: $title, content: $content, categoryIds: $categoryIds) {
+      id
+      title
+      content
+    }
+  }
+`
+const updatePostMutation = gql`
+  mutation($id: ID!, $title: String!, $content: String!, $categoryIds: [ID]!) {
+    UpdatePost(id: $id, content: $content, title: $title, categoryIds: $categoryIds) {
+      title
+      content
+    }
+  }
+`
 
 beforeAll(() => {
   const createServerResult = createServer({
@@ -37,6 +55,11 @@ beforeEach(async () => {
     email: 'test@example.org',
     password: '1234',
   })
+  await instance.create('Category', {
+    id: 'cat9',
+    name: 'Democracy & Politics',
+    icon: 'university',
+  })
 })
 
 afterEach(async () => {
@@ -78,19 +101,10 @@ describe('notifications', () => {
           'Hey <a class="mention" data-mention-id="you" href="/profile/you/al-capone">@al-capone</a> how do you do?'
 
         const createPostAction = async () => {
-          const createPostMutation = gql`
-            mutation($id: ID, $title: String!, $content: String!) {
-              CreatePost(id: $id, title: $title, content: $content) {
-                id
-                title
-                content
-              }
-            }
-          `
           authenticatedUser = await author.toJson()
           await mutate({
             mutation: createPostMutation,
-            variables: { id: 'p47', title, content },
+            variables: { id: 'p47', title, content, categoryIds },
           })
           authenticatedUser = await user.toJson()
         }
@@ -126,14 +140,6 @@ describe('notifications', () => {
                 @al-capone
               </a>
             `
-            const updatePostMutation = gql`
-              mutation($id: ID!, $title: String!, $content: String!) {
-                UpdatePost(id: $id, content: $content, title: $title) {
-                  title
-                  content
-                }
-              }
-            `
             authenticatedUser = await author.toJson()
             await mutate({
               mutation: updatePostMutation,
@@ -141,6 +147,7 @@ describe('notifications', () => {
                 id: 'p47',
                 title,
                 content: updatedContent,
+                categoryIds,
               },
             })
             authenticatedUser = await user.toJson()
@@ -189,9 +196,9 @@ describe('notifications', () => {
 })
 
 describe('Hashtags', () => {
-  const postId = 'p135'
-  const postTitle = 'Two Hashtags'
-  const postContent =
+  const id = 'p135'
+  const title = 'Two Hashtags'
+  const content =
     '<p>Hey Dude, <a class="hashtag" href="/search/hashtag/Democracy">#Democracy</a> should work equal for everybody!? That seems to be the only way to have equal <a class="hashtag" href="/search/hashtag/Liberty">#Liberty</a> for everyone.</p>'
   const postWithHastagsQuery = gql`
     query($id: ID) {
@@ -203,17 +210,8 @@ describe('Hashtags', () => {
     }
   `
   const postWithHastagsVariables = {
-    id: postId,
+    id,
   }
-  const createPostMutation = gql`
-    mutation($postId: ID, $postTitle: String!, $postContent: String!) {
-      CreatePost(id: $postId, title: $postTitle, content: $postContent) {
-        id
-        title
-        content
-      }
-    }
-  `
 
   describe('authenticated', () => {
     beforeEach(async () => {
@@ -225,9 +223,10 @@ describe('Hashtags', () => {
         await mutate({
           mutation: createPostMutation,
           variables: {
-            postId,
-            postTitle,
-            postContent,
+            id,
+            title,
+            content,
+            categoryIds,
           },
         })
       })
@@ -251,25 +250,17 @@ describe('Hashtags', () => {
 
       describe('afterwards update the Post by removing a Hashtag, leaving a Hashtag and add a Hashtag', () => {
         // The already existing Hashtag has no class at this point.
-        const updatedPostContent =
+        const content =
           '<p>Hey Dude, <a class="hashtag" href="/search/hashtag/Elections">#Elections</a> should work equal for everybody!? That seems to be the only way to have equal <a href="/search/hashtag/Liberty">#Liberty</a> for everyone.</p>'
-        const updatePostMutation = gql`
-          mutation($postId: ID!, $postTitle: String!, $updatedPostContent: String!) {
-            UpdatePost(id: $postId, title: $postTitle, content: $updatedPostContent) {
-              id
-              title
-              content
-            }
-          }
-        `
 
         it('only one previous Hashtag and the new Hashtag exists', async () => {
           await mutate({
             mutation: updatePostMutation,
             variables: {
-              postId,
-              postTitle,
-              updatedPostContent,
+              id,
+              title,
+              content,
+              categoryIds,
             },
           })
 
diff --git a/backend/src/middleware/slugifyMiddleware.spec.js b/backend/src/middleware/slugifyMiddleware.spec.js
index 5ee4faa3c..0f42def85 100644
--- a/backend/src/middleware/slugifyMiddleware.spec.js
+++ b/backend/src/middleware/slugifyMiddleware.spec.js
@@ -1,13 +1,25 @@
 import { GraphQLClient } from 'graphql-request'
 import Factory from '../seed/factories'
-import { host, login } from '../jest/helpers'
+import { host, login, gql } from '../jest/helpers'
 import { neode } from '../bootstrap/neo4j'
 
 let authenticatedClient
 let headers
 const factory = Factory()
 const instance = neode()
-
+const categoryIds = ['cat9']
+const createPostMutation = gql`
+  mutation($title: String!, $content: String!, $categoryIds: [ID]!, $slug: String) {
+    CreatePost(title: $title, content: $content, categoryIds: $categoryIds, slug: $slug) {
+      slug
+    }
+  }
+`
+let createPostVariables = {
+  title: 'I am a brand new post',
+  content: 'Some content',
+  categoryIds,
+}
 beforeEach(async () => {
   const adminParams = { role: 'admin', email: 'admin@example.org', password: '1234' }
   await factory.create('User', adminParams)
@@ -15,6 +27,11 @@ beforeEach(async () => {
     email: 'someone@example.org',
     password: '1234',
   })
+  await instance.create('Category', {
+    id: 'cat9',
+    name: 'Democracy & Politics',
+    icon: 'university',
+  })
   // we need to be an admin, otherwise we're not authorized to create a user
   headers = await login(adminParams)
   authenticatedClient = new GraphQLClient(host, { headers })
@@ -27,12 +44,7 @@ afterEach(async () => {
 describe('slugify', () => {
   describe('CreatePost', () => {
     it('generates a slug based on title', async () => {
-      const response = await authenticatedClient.request(`mutation {
-        CreatePost(
-          title: "I am a brand new post",
-          content: "Some content"
-        ) { slug }
-      }`)
+      const response = await authenticatedClient.request(createPostMutation, createPostVariables)
       expect(response).toEqual({
         CreatePost: { slug: 'i-am-a-brand-new-post' },
       })
@@ -47,16 +59,14 @@ describe('slugify', () => {
         await asSomeoneElse.create('Post', {
           title: 'Pre-existing post',
           slug: 'pre-existing-post',
+          content: 'as Someone else content',
+          categoryIds,
         })
       })
 
       it('chooses another slug', async () => {
-        const response = await authenticatedClient.request(`mutation {
-          CreatePost(
-            title: "Pre-existing post",
-            content: "Some content"
-          ) { slug }
-        }`)
+        createPostVariables = { title: 'Pre-existing post', content: 'Some content', categoryIds }
+        const response = await authenticatedClient.request(createPostMutation, createPostVariables)
         expect(response).toEqual({
           CreatePost: { slug: 'pre-existing-post-1' },
         })
@@ -64,14 +74,14 @@ describe('slugify', () => {
 
       describe('but if the client specifies a slug', () => {
         it('rejects CreatePost', async () => {
+          createPostVariables = {
+            title: 'Pre-existing post',
+            content: 'Some content',
+            slug: 'pre-existing-post',
+            categoryIds,
+          }
           await expect(
-            authenticatedClient.request(`mutation {
-              CreatePost(
-                title: "Pre-existing post",
-                content: "Some content",
-                slug: "pre-existing-post"
-              ) { slug }
-            }`),
+            authenticatedClient.request(createPostMutation, createPostVariables),
           ).rejects.toThrow('already exists')
         })
       })
diff --git a/backend/src/middleware/softDeleteMiddleware.spec.js b/backend/src/middleware/softDeleteMiddleware.spec.js
index 388f44a3c..03c97c020 100644
--- a/backend/src/middleware/softDeleteMiddleware.spec.js
+++ b/backend/src/middleware/softDeleteMiddleware.spec.js
@@ -1,11 +1,15 @@
 import { GraphQLClient } from 'graphql-request'
 import Factory from '../seed/factories'
 import { host, login } from '../jest/helpers'
+import { neode } from '../bootstrap/neo4j'
 
 const factory = Factory()
+const instance = neode()
+
 let client
 let query
 let action
+const categoryIds = ['cat9']
 
 beforeAll(async () => {
   // For performance reasons we do this only once
@@ -26,13 +30,23 @@ beforeAll(async () => {
       email: 'troll@example.org',
       password: '1234',
     }),
+    instance.create('Category', {
+      id: 'cat9',
+      name: 'Democracy & Politics',
+      icon: 'university',
+    }),
   ])
 
   await factory.authenticateAs({ email: 'user@example.org', password: '1234' })
   await Promise.all([
     factory.follow({ id: 'u2', type: 'User' }),
-    factory.create('Post', { id: 'p1', title: 'Deleted post', deleted: true }),
-    factory.create('Post', { id: 'p3', title: 'Publicly visible post', deleted: false }),
+    factory.create('Post', { id: 'p1', title: 'Deleted post', deleted: true, categoryIds }),
+    factory.create('Post', {
+      id: 'p3',
+      title: 'Publicly visible post',
+      deleted: false,
+      categoryIds,
+    }),
   ])
 
   await Promise.all([
@@ -53,6 +67,7 @@ beforeAll(async () => {
     content: 'This is an offensive post content',
     image: '/some/offensive/image.jpg',
     deleted: false,
+    categoryIds,
   })
   await asTroll.create('Comment', { id: 'c1', postId: 'p3', content: 'Disabled comment' })
   await Promise.all([asTroll.relate('Comment', 'Author', { from: 'u2', to: 'c1' })])
diff --git a/backend/src/models/Category.js b/backend/src/models/Category.js
new file mode 100644
index 000000000..d8f1bff6f
--- /dev/null
+++ b/backend/src/models/Category.js
@@ -0,0 +1,21 @@
+import uuid from 'uuid/v4'
+
+module.exports = {
+  id: { type: 'string', primary: true, default: uuid },
+  name: { type: 'string', required: true, default: false },
+  slug: { type: 'string' },
+  icon: { type: 'string', required: true, default: false },
+  createdAt: { type: 'string', isoDate: true, default: () => new Date().toISOString() },
+  updatedAt: {
+    type: 'string',
+    isoDate: true,
+    required: true,
+    default: () => new Date().toISOString(),
+  },
+  post: {
+    type: 'relationship',
+    relationship: 'CATEGORIZED',
+    target: 'Post',
+    direction: 'in',
+  },
+}
diff --git a/backend/src/models/index.js b/backend/src/models/index.js
index 6f6b300f8..295082de4 100644
--- a/backend/src/models/index.js
+++ b/backend/src/models/index.js
@@ -8,4 +8,5 @@ export default {
   SocialMedia: require('./SocialMedia.js'),
   Post: require('./Post.js'),
   Notification: require('./Notification.js'),
+  Category: require('./Category.js'),
 }
diff --git a/backend/src/schema/resolvers/comments.spec.js b/backend/src/schema/resolvers/comments.spec.js
index e8280bd4b..0b6d5f727 100644
--- a/backend/src/schema/resolvers/comments.spec.js
+++ b/backend/src/schema/resolvers/comments.spec.js
@@ -1,18 +1,21 @@
 import { GraphQLClient } from 'graphql-request'
 import Factory from '../../seed/factories'
 import { host, login, gql } from '../../jest/helpers'
+import { neode } from '../../bootstrap/neo4j'
 
-const factory = Factory()
 let client
 let createCommentVariables
 let createCommentVariablesSansPostId
 let createCommentVariablesWithNonExistentPost
 let userParams
 let headers
+const factory = Factory()
+const instance = neode()
+const categoryIds = ['cat9']
 
 const createPostMutation = gql`
-  mutation($id: ID!, $title: String!, $content: String!) {
-    CreatePost(id: $id, title: $title, content: $content) {
+  mutation($id: ID, $title: String!, $content: String!, $categoryIds: [ID]!) {
+    CreatePost(id: $id, title: $title, content: $content, categoryIds: $categoryIds) {
       id
     }
   }
@@ -29,6 +32,7 @@ const createPostVariables = {
   id: 'p1',
   title: 'post to comment on',
   content: 'please comment on me',
+  categoryIds,
 }
 
 beforeEach(async () => {
@@ -38,6 +42,11 @@ beforeEach(async () => {
     password: '1234',
   }
   await factory.create('User', userParams)
+  await instance.create('Category', {
+    id: 'cat9',
+    name: 'Democracy & Politics',
+    icon: 'university',
+  })
 })
 
 afterEach(async () => {
@@ -199,6 +208,7 @@ describe('ManageComments', () => {
     await asAuthor.create('Post', {
       id: 'p1',
       content: 'Post to be commented',
+      categoryIds,
     })
     await asAuthor.create('Comment', {
       id: 'c456',
diff --git a/backend/src/schema/resolvers/moderation.spec.js b/backend/src/schema/resolvers/moderation.spec.js
index db679f522..3107a5799 100644
--- a/backend/src/schema/resolvers/moderation.spec.js
+++ b/backend/src/schema/resolvers/moderation.spec.js
@@ -1,9 +1,12 @@
 import { GraphQLClient } from 'graphql-request'
 import Factory from '../../seed/factories'
-import { host, login } from '../../jest/helpers'
+import { host, login, gql } from '../../jest/helpers'
+import { neode } from '../../bootstrap/neo4j'
 
-const factory = Factory()
 let client
+const factory = Factory()
+const instance = neode()
+const categoryIds = ['cat9']
 
 const setupAuthenticateClient = params => {
   const authenticateClient = async () => {
@@ -19,11 +22,16 @@ let authenticateClient
 let createPostVariables
 let createCommentVariables
 
-beforeEach(() => {
+beforeEach(async () => {
   createResource = () => {}
   authenticateClient = () => {
     client = new GraphQLClient(host)
   }
+  await instance.create('Category', {
+    id: 'cat9',
+    name: 'Democracy & Politics',
+    icon: 'university',
+  })
 })
 
 const setup = async () => {
@@ -36,7 +44,7 @@ afterEach(async () => {
 })
 
 describe('disable', () => {
-  const mutation = `
+  const mutation = gql`
     mutation($id: ID!) {
       disable(id: $id)
     }
@@ -108,6 +116,7 @@ describe('disable', () => {
             id: 'p3',
             title: 'post to comment on',
             content: 'please comment on me',
+            categoryIds,
           }
           createCommentVariables = {
             id: 'c47',
@@ -173,6 +182,7 @@ describe('disable', () => {
             await factory.authenticateAs({ email: 'author@example.org', password: '1234' })
             await factory.create('Post', {
               id: 'p9', // that's the ID we will look for
+              categoryIds,
             })
           }
         })
@@ -214,7 +224,7 @@ describe('disable', () => {
 })
 
 describe('enable', () => {
-  const mutation = `
+  const mutation = gql`
     mutation($id: ID!) {
       enable(id: $id)
     }
@@ -286,6 +296,7 @@ describe('enable', () => {
             id: 'p9',
             title: 'post to comment on',
             content: 'please comment on me',
+            categoryIds,
           }
           createCommentVariables = {
             id: 'c456',
@@ -305,7 +316,7 @@ describe('enable', () => {
             await asAuthenticatedUser.create('Post', createPostVariables)
             await asAuthenticatedUser.create('Comment', createCommentVariables)
 
-            const disableMutation = `
+            const disableMutation = gql`
               mutation {
                 disable(id: "c456")
               }
@@ -362,9 +373,10 @@ describe('enable', () => {
             await factory.authenticateAs({ email: 'author@example.org', password: '1234' })
             await factory.create('Post', {
               id: 'p9', // that's the ID we will look for
+              categoryIds,
             })
 
-            const disableMutation = `
+            const disableMutation = gql`
               mutation {
                 disable(id: "p9")
               }
diff --git a/backend/src/schema/resolvers/notifications.spec.js b/backend/src/schema/resolvers/notifications.spec.js
index 8d51ebfbb..47bb0d515 100644
--- a/backend/src/schema/resolvers/notifications.spec.js
+++ b/backend/src/schema/resolvers/notifications.spec.js
@@ -1,17 +1,25 @@
 import { GraphQLClient } from 'graphql-request'
 import Factory from '../../seed/factories'
-import { host, login } from '../../jest/helpers'
+import { host, login, gql } from '../../jest/helpers'
+import { neode } from '../../bootstrap/neo4j'
 
-const factory = Factory()
 let client
+const factory = Factory()
+const instance = neode()
 const userParams = {
   id: 'you',
   email: 'test@example.org',
   password: '1234',
 }
+const categoryIds = ['cat9']
 
 beforeEach(async () => {
   await factory.create('User', userParams)
+  await instance.create('Category', {
+    id: 'cat9',
+    name: 'Democracy & Politics',
+    icon: 'university',
+  })
 })
 
 afterEach(async () => {
@@ -19,11 +27,13 @@ afterEach(async () => {
 })
 
 describe('Notification', () => {
-  const query = `{
-    Notification {
-      id
+  const query = gql`
+    query {
+      Notification {
+        id
+      }
     }
-  }`
+  `
 
   describe('unauthenticated', () => {
     it('throws authorization error', async () => {
@@ -57,28 +67,30 @@ describe('currentUser { notifications }', () => {
         ])
         await factory.create('Notification', { id: 'unseen' })
         await factory.authenticateAs(neighborParams)
-        await factory.create('Post', { id: 'p1' })
+        await factory.create('Post', { id: 'p1', categoryIds })
         await Promise.all([
           factory.relate('Notification', 'User', { from: 'not-for-you', to: 'neighbor' }),
-          factory.relate('Notification', 'Post', { from: 'p1', to: 'not-for-you' }),
+          factory.relate('Notification', 'Post', { from: 'p1', to: 'not-for-you', categoryIds }),
           factory.relate('Notification', 'User', { from: 'unseen', to: 'you' }),
-          factory.relate('Notification', 'Post', { from: 'p1', to: 'unseen' }),
+          factory.relate('Notification', 'Post', { from: 'p1', to: 'unseen', categoryIds }),
           factory.relate('Notification', 'User', { from: 'already-seen', to: 'you' }),
-          factory.relate('Notification', 'Post', { from: 'p1', to: 'already-seen' }),
+          factory.relate('Notification', 'Post', { from: 'p1', to: 'already-seen', categoryIds }),
         ])
       })
 
       describe('filter for read: false', () => {
-        const query = `query($read: Boolean) {
-          currentUser {
-            notifications(read: $read, orderBy: createdAt_desc) {
-              id
-              post {
+        const query = gql`
+          query($read: Boolean) {
+            currentUser {
+              notifications(read: $read, orderBy: createdAt_desc) {
                 id
+                post {
+                  id
+                }
               }
             }
           }
-        }`
+        `
         const variables = { read: false }
         it('returns only unread notifications of current user', async () => {
           const expected = {
@@ -91,16 +103,18 @@ describe('currentUser { notifications }', () => {
       })
 
       describe('no filters', () => {
-        const query = `{
-          currentUser {
-            notifications(orderBy: createdAt_desc) {
-              id
-              post {
+        const query = gql`
+          query {
+            currentUser {
+              notifications(orderBy: createdAt_desc) {
                 id
+                post {
+                  id
+                }
               }
             }
           }
-        }`
+        `
         it('returns all notifications of current user', async () => {
           const expected = {
             currentUser: {
@@ -118,11 +132,14 @@ describe('currentUser { notifications }', () => {
 })
 
 describe('UpdateNotification', () => {
-  const mutation = `mutation($id: ID!, $read: Boolean){
-    UpdateNotification(id: $id, read: $read) {
-      id read
+  const mutation = gql`
+    mutation($id: ID!, $read: Boolean) {
+      UpdateNotification(id: $id, read: $read) {
+        id
+        read
+      }
     }
-  }`
+  `
   const variables = { id: 'to-be-updated', read: true }
 
   describe('given a notifications', () => {
@@ -138,7 +155,7 @@ describe('UpdateNotification', () => {
       await factory.create('User', mentionedParams)
       await factory.create('Notification', { id: 'to-be-updated' })
       await factory.authenticateAs(userParams)
-      await factory.create('Post', { id: 'p1' })
+      await factory.create('Post', { id: 'p1', categoryIds })
       await Promise.all([
         factory.relate('Notification', 'User', { from: 'to-be-updated', to: 'mentioned-1' }),
         factory.relate('Notification', 'Post', { from: 'p1', to: 'to-be-updated' }),
diff --git a/backend/src/schema/resolvers/reports.spec.js b/backend/src/schema/resolvers/reports.spec.js
index 2a798f5ee..7287a79f4 100644
--- a/backend/src/schema/resolvers/reports.spec.js
+++ b/backend/src/schema/resolvers/reports.spec.js
@@ -1,8 +1,10 @@
 import { GraphQLClient } from 'graphql-request'
 import Factory from '../../seed/factories'
 import { host, login } from '../../jest/helpers'
+import { neode } from '../../bootstrap/neo4j'
 
 const factory = Factory()
+const instance = neode()
 
 describe('report', () => {
   let mutation
@@ -10,6 +12,7 @@ describe('report', () => {
   let returnedObject
   let variables
   let createPostVariables
+  const categoryIds = ['cat9']
 
   beforeEach(async () => {
     returnedObject = '{ description }'
@@ -28,6 +31,11 @@ describe('report', () => {
       role: 'user',
       email: 'abusive-user@example.org',
     })
+    await instance.create('Category', {
+      id: 'cat9',
+      name: 'Democracy & Politics',
+      icon: 'university',
+    })
   })
 
   afterEach(async () => {
@@ -126,6 +134,7 @@ describe('report', () => {
             await factory.create('Post', {
               id: 'p23',
               title: 'Matt and Robert having a pair-programming',
+              categoryIds,
             })
             variables = {
               id: 'p23',
@@ -171,6 +180,7 @@ describe('report', () => {
               id: 'p1',
               title: 'post to comment on',
               content: 'please comment on me',
+              categoryIds,
             }
             const asAuthenticatedUser = await factory.authenticateAs({
               email: 'test@example.org',
diff --git a/backend/src/schema/resolvers/shout.spec.js b/backend/src/schema/resolvers/shout.spec.js
index 029e6998c..718a1e169 100644
--- a/backend/src/schema/resolvers/shout.spec.js
+++ b/backend/src/schema/resolvers/shout.spec.js
@@ -1,22 +1,39 @@
 import { GraphQLClient } from 'graphql-request'
 import Factory from '../../seed/factories'
-import { host, login } from '../../jest/helpers'
+import { host, login, gql } from '../../jest/helpers'
+import { neode } from '../../bootstrap/neo4j'
 
-const factory = Factory()
 let clientUser1, clientUser2
 let headersUser1, headersUser2
+const factory = Factory()
+const instance = neode()
+const categoryIds = ['cat9']
 
-const mutationShoutPost = id => `
-  mutation {
-    shout(id: "${id}", type: Post)
+const mutationShoutPost = gql`
+  mutation($id: ID!) {
+    shout(id: $id, type: Post)
   }
 `
-const mutationUnshoutPost = id => `
-  mutation {
-    unshout(id: "${id}", type: Post)
+const mutationUnshoutPost = gql`
+  mutation($id: ID!) {
+    unshout(id: $id, type: Post)
   }
 `
-
+const createPostMutation = gql`
+  mutation($id: ID, $title: String!, $content: String!, $categoryIds: [ID]!) {
+    CreatePost(id: $id, title: $title, content: $content, categoryIds: $categoryIds) {
+      id
+      title
+      content
+    }
+  }
+`
+const createPostVariables = {
+  id: 'p1234',
+  title: 'Post Title 1234',
+  content: 'Some Post Content 1234',
+  categoryIds,
+}
 beforeEach(async () => {
   await factory.create('User', {
     id: 'u1',
@@ -28,28 +45,23 @@ beforeEach(async () => {
     email: 'test2@example.org',
     password: '1234',
   })
-
+  await instance.create('Category', {
+    id: 'cat9',
+    name: 'Democracy & Politics',
+    icon: 'university',
+  })
   headersUser1 = await login({ email: 'test@example.org', password: '1234' })
   headersUser2 = await login({ email: 'test2@example.org', password: '1234' })
   clientUser1 = new GraphQLClient(host, { headers: headersUser1 })
   clientUser2 = new GraphQLClient(host, { headers: headersUser2 })
 
-  await clientUser1.request(`
-    mutation {
-      CreatePost(id: "p1", title: "Post Title 1", content: "Some Post Content 1") {
-        id
-        title
-      }
-    }
-  `)
-  await clientUser2.request(`
-  mutation {
-      CreatePost(id: "p2", title: "Post Title 2", content: "Some Post Content 2") {
-        id
-        title
-      }
-    }
-  `)
+  await clientUser1.request(createPostMutation, createPostVariables)
+  await clientUser2.request(createPostMutation, {
+    id: 'p12345',
+    title: 'Post Title 12345',
+    content: 'Some Post Content 12345',
+    categoryIds,
+  })
 })
 
 afterEach(async () => {
@@ -61,22 +73,26 @@ describe('shout', () => {
     describe('unauthenticated shout', () => {
       it('throws authorization error', async () => {
         const client = new GraphQLClient(host)
-        await expect(client.request(mutationShoutPost('p1'))).rejects.toThrow('Not Authorised')
+        await expect(client.request(mutationShoutPost, { id: 'p1234' })).rejects.toThrow(
+          'Not Authorised',
+        )
       })
     })
 
     it('I shout a post of another user', async () => {
-      const res = await clientUser1.request(mutationShoutPost('p2'))
+      const res = await clientUser1.request(mutationShoutPost, { id: 'p12345' })
       const expected = {
         shout: true,
       }
       expect(res).toMatchObject(expected)
 
-      const { Post } = await clientUser1.request(`{
-        Post(id: "p2") {
-          shoutedByCurrentUser
+      const { Post } = await clientUser1.request(gql`
+        query {
+          Post(id: "p12345") {
+            shoutedByCurrentUser
+          }
         }
-      }`)
+      `)
       const expected2 = {
         shoutedByCurrentUser: true,
       }
@@ -84,17 +100,19 @@ describe('shout', () => {
     })
 
     it('I can`t shout my own post', async () => {
-      const res = await clientUser1.request(mutationShoutPost('p1'))
+      const res = await clientUser1.request(mutationShoutPost, { id: 'p1234' })
       const expected = {
         shout: false,
       }
       expect(res).toMatchObject(expected)
 
-      const { Post } = await clientUser1.request(`{
-        Post(id: "p1") {
-          shoutedByCurrentUser
+      const { Post } = await clientUser1.request(gql`
+        query {
+          Post(id: "p1234") {
+            shoutedByCurrentUser
+          }
         }
-      }`)
+      `)
       const expected2 = {
         shoutedByCurrentUser: false,
       }
@@ -106,28 +124,32 @@ describe('shout', () => {
     describe('unauthenticated shout', () => {
       it('throws authorization error', async () => {
         // shout
-        await clientUser1.request(mutationShoutPost('p2'))
+        await clientUser1.request(mutationShoutPost, { id: 'p12345' })
         // unshout
         const client = new GraphQLClient(host)
-        await expect(client.request(mutationUnshoutPost('p2'))).rejects.toThrow('Not Authorised')
+        await expect(client.request(mutationUnshoutPost, { id: 'p12345' })).rejects.toThrow(
+          'Not Authorised',
+        )
       })
     })
 
     it('I unshout a post of another user', async () => {
       // shout
-      await clientUser1.request(mutationShoutPost('p2'))
+      await clientUser1.request(mutationShoutPost, { id: 'p12345' })
       const expected = {
         unshout: true,
       }
       // unshout
-      const res = await clientUser1.request(mutationUnshoutPost('p2'))
+      const res = await clientUser1.request(mutationUnshoutPost, { id: 'p12345' })
       expect(res).toMatchObject(expected)
 
-      const { Post } = await clientUser1.request(`{
-        Post(id: "p2") {
-          shoutedByCurrentUser
+      const { Post } = await clientUser1.request(gql`
+        query {
+          Post(id: "p12345") {
+            shoutedByCurrentUser
+          }
         }
-      }`)
+      `)
       const expected2 = {
         shoutedByCurrentUser: false,
       }
diff --git a/backend/src/schema/resolvers/users.spec.js b/backend/src/schema/resolvers/users.spec.js
index fff6acadb..454b457e6 100644
--- a/backend/src/schema/resolvers/users.spec.js
+++ b/backend/src/schema/resolvers/users.spec.js
@@ -1,9 +1,12 @@
 import { GraphQLClient } from 'graphql-request'
 import Factory from '../../seed/factories'
 import { host, login, gql } from '../../jest/helpers'
+import { neode } from '../../bootstrap/neo4j'
 
-const factory = Factory()
 let client
+const factory = Factory()
+const instance = neode()
+const categoryIds = ['cat9']
 
 afterEach(async () => {
   await factory.cleanDatabase()
@@ -195,9 +198,15 @@ describe('users', () => {
             email: 'test@example.org',
             password: '1234',
           })
+          await instance.create('Category', {
+            id: 'cat9',
+            name: 'Democracy & Politics',
+            icon: 'university',
+          })
           await asAuthor.create('Post', {
             id: 'p139',
             content: 'Post by user u343',
+            categoryIds,
           })
           await asAuthor.create('Comment', {
             id: 'c155',