diff --git a/server/configure.js b/server/configure.js
index 0766d695..bc6a282c 100644
--- a/server/configure.js
+++ b/server/configure.js
@@ -81,9 +81,9 @@ module.exports = (port, spinner) => {
       () => {
         const semver = require('semver')
         if (!semver.satisfies(semver.clean(process.version), '>=6.9.0')) {
-          throw new Error('Node.js version is too old. Minimum is v6.6.0.')
+          throw new Error('Node.js version is too old. Minimum is v6.11.1.')
         }
-        return 'Node.js ' + process.version + ' detected. Minimum is v6.9.0.'
+        return 'Node.js ' + process.version + ' detected.'
       },
       () => {
         return Promise.try(() => {
@@ -110,10 +110,10 @@ module.exports = (port, spinner) => {
       },
       () => {
         const os = require('os')
-        if (os.totalmem() < 1000 * 1000 * 768) {
-          throw new Error('Not enough memory. Minimum is 768 MB.')
+        if (os.totalmem() < 1000 * 1000 * 512) {
+          throw new Error('Not enough memory. Minimum is 512 MB.')
         }
-        return _.round(os.totalmem() / (1024 * 1024)) + ' MB of system memory available. Minimum is 768 MB.'
+        return _.round(os.totalmem() / (1024 * 1024)) + ' MB of system memory available. Minimum is 512 MB.'
       },
       () => {
         let fs = require('fs')
diff --git a/server/modules/graphql.js b/server/modules/graphql.js
index ed6f776c..a7f073b1 100644
--- a/server/modules/graphql.js
+++ b/server/modules/graphql.js
@@ -9,12 +9,14 @@ const _ = require('lodash')
 
 const typeDefs = fs.readFileSync(path.join(wiki.SERVERPATH, 'schemas/types.graphql'), 'utf8')
 
+const DateScalar = require('../schemas/scalar-date')
 const GroupResolvers = require('../schemas/resolvers-group')
 const UserResolvers = require('../schemas/resolvers-user')
 
 const resolvers = _.merge(
   GroupResolvers,
-  UserResolvers
+  UserResolvers,
+  DateScalar
 )
 
 const Schema = gqlTools.makeExecutableSchema({
diff --git a/server/schemas/scalar-date.js b/server/schemas/scalar-date.js
new file mode 100644
index 00000000..6fa5b585
--- /dev/null
+++ b/server/schemas/scalar-date.js
@@ -0,0 +1,22 @@
+'use strict'
+
+const gql = require('graphql')
+
+module.exports = {
+  Date: new gql.GraphQLScalarType({
+    name: 'Date',
+    description: 'ISO date-time string at UTC',
+    parseValue(value) {
+      return new Date(value)
+    },
+    serialize(value) {
+      return value.toISOString()
+    },
+    parseLiteral(ast) {
+      if (ast.kind !== gql.Kind.STRING) {
+        throw new TypeError('Date value must be an string!')
+      }
+      return new Date(ast.value)
+    }
+  })
+}
diff --git a/server/schemas/types.graphql b/server/schemas/types.graphql
index a7e6e20d..95ce6ff8 100644
--- a/server/schemas/types.graphql
+++ b/server/schemas/types.graphql
@@ -25,16 +25,16 @@ enum RightRole {
 
 interface Base {
   id: Int!
-  createdOn: Date
-  updatedOn: Date
+  createdAt: Date
+  updatedAt: Date
 }
 
 # TYPES
 
 type Comment implements Base {
   id: Int!
-  createdOn: Date
-  updatedOn: Date
+  createdAt: Date
+  updatedAt: Date
   content: String
   document: Document!
   author: User!
@@ -42,8 +42,8 @@ type Comment implements Base {
 
 type Document implements Base {
   id: Int!
-  createdOn: Date
-  updatedOn: Date
+  createdAt: Date
+  updatedAt: Date
   path: String!
   title: String!
   subtitle: String
@@ -57,8 +57,8 @@ type Document implements Base {
 
 type File implements Base {
   id: Int!
-  createdOn: Date
-  updatedOn: Date
+  createdAt: Date
+  updatedAt: Date
   category: FileType!
   mime: String!
   extra: String
@@ -70,15 +70,15 @@ type File implements Base {
 
 type Folder implements Base {
   id: Int!
-  createdOn: Date
-  updatedOn: Date
+  createdAt: Date
+  updatedAt: Date
   name: String!
 }
 
 type Group implements Base {
   id: Int!
-  createdOn: Date
-  updatedOn: Date
+  createdAt: Date
+  updatedAt: Date
   name: String!
   users: [User]
   rights: [Right]
@@ -86,8 +86,8 @@ type Group implements Base {
 
 type Right implements Base {
   id: Int!
-  createdOn: Date
-  updatedOn: Date
+  createdAt: Date
+  updatedAt: Date
   path: String!
   role: RightRole!
   exact: Boolean!
@@ -96,8 +96,8 @@ type Right implements Base {
 
 type Setting implements Base {
   id: Int!
-  createdOn: Date
-  updatedOn: Date
+  createdAt: Date
+  updatedAt: Date
   key: String!
   config: String!
 }
@@ -105,16 +105,16 @@ type Setting implements Base {
 # Tags are attached to one or more documents
 type Tag implements Base {
   id: Int!
-  createdOn: Date
-  updatedOn: Date
+  createdAt: Date
+  updatedAt: Date
   key: String!
 }
 
 # A User
 type User implements Base {
   id: Int!
-  createdOn: Date
-  updatedOn: Date
+  createdAt: Date
+  updatedAt: Date
   email: String!
   provider: String!
   providerId: String