diff --git a/test/api/unit/libs/baseModel.test.js b/test/api/unit/libs/baseModel.test.js
index a9c826bfa5..28e85aea50 100644
--- a/test/api/unit/libs/baseModel.test.js
+++ b/test/api/unit/libs/baseModel.test.js
@@ -5,10 +5,17 @@ describe('Base model plugin', () => {
   let schema;
 
   beforeEach(() => {
-    schema = new mongoose.Schema();
+    schema = new mongoose.Schema({}, {
+      typeKey: '$type',
+    });
     sandbox.stub(schema, 'add');
   });
 
+  it('throws if "typeKey" is not set to $type', () => {
+    const schemaWithoutTypeKey = new mongoose.Schema();
+    expect(() => schemaWithoutTypeKey.plugin(baseModel)).to.throw;
+  });
+
   it('adds a _id field to the schema', () => {
     schema.plugin(baseModel);
 
diff --git a/website/server/libs/baseModel.js b/website/server/libs/baseModel.js
index 4ed6d0aad7..3a6e7b16a1 100644
--- a/website/server/libs/baseModel.js
+++ b/website/server/libs/baseModel.js
@@ -3,10 +3,14 @@ import validator from 'validator';
 import _ from 'lodash';
 
 module.exports = function baseModel (schema, options = {}) {
+  if (schema.options.typeKey !== '$type') {
+    throw new Error('Every schema must use $type as the typeKey, see https://mongoosejs.com/docs/guide.html#typeKey');
+  }
+
   if (options._id !== false) {
     schema.add({
       _id: {
-        type: String,
+        $type: String,
         default: uuid,
         validate: [v => validator.isUUID(v), 'Invalid uuid.'],
       },
@@ -16,11 +20,11 @@ module.exports = function baseModel (schema, options = {}) {
   if (options.timestamps) {
     schema.add({
       createdAt: {
-        type: Date,
+        $type: Date,
         default: Date.now,
       },
       updatedAt: {
-        type: Date,
+        $type: Date,
         default: Date.now,
       },
     });
diff --git a/website/server/models/challenge.js b/website/server/models/challenge.js
index d0f02c41c4..2bb773f925 100644
--- a/website/server/models/challenge.js
+++ b/website/server/models/challenge.js
@@ -20,28 +20,29 @@ const MIN_SHORTNAME_SIZE_FOR_CHALLENGES = shared.constants.MIN_SHORTNAME_SIZE_FO
 const MAX_SUMMARY_SIZE_FOR_CHALLENGES = shared.constants.MAX_SUMMARY_SIZE_FOR_CHALLENGES;
 
 let schema = new Schema({
-  name: {type: String, required: true},
-  shortName: {type: String, required: true, minlength: MIN_SHORTNAME_SIZE_FOR_CHALLENGES},
-  summary: {type: String, maxlength: MAX_SUMMARY_SIZE_FOR_CHALLENGES},
+  name: {$type: String, required: true},
+  shortName: {$type: String, required: true, minlength: MIN_SHORTNAME_SIZE_FOR_CHALLENGES},
+  summary: {$type: String, maxlength: MAX_SUMMARY_SIZE_FOR_CHALLENGES},
   description: String,
-  official: {type: Boolean, default: false},
+  official: {$type: Boolean, default: false},
   tasksOrder: {
-    habits: [{type: String, ref: 'Task'}],
-    dailys: [{type: String, ref: 'Task'}],
-    todos: [{type: String, ref: 'Task'}],
-    rewards: [{type: String, ref: 'Task'}],
+    habits: [{$type: String, ref: 'Task'}],
+    dailys: [{$type: String, ref: 'Task'}],
+    todos: [{$type: String, ref: 'Task'}],
+    rewards: [{$type: String, ref: 'Task'}],
   },
-  leader: {type: String, ref: 'User', validate: [v => validator.isUUID(v), 'Invalid uuid.'], required: true},
-  group: {type: String, ref: 'Group', validate: [v => validator.isUUID(v), 'Invalid uuid.'], required: true},
-  memberCount: {type: Number, default: 0},
-  prize: {type: Number, default: 0, min: 0},
+  leader: {$type: String, ref: 'User', validate: [v => validator.isUUID(v), 'Invalid uuid.'], required: true},
+  group: {$type: String, ref: 'Group', validate: [v => validator.isUUID(v), 'Invalid uuid.'], required: true},
+  memberCount: {$type: Number, default: 0},
+  prize: {$type: Number, default: 0, min: 0},
   categories: [{
-    slug: {type: String},
-    name: {type: String},
+    slug: {$type: String},
+    name: {$type: String},
   }],
 }, {
   strict: true,
   minimize: false, // So empty objects are returned
+  typeKey: '$type', // So that we can use fields named `type`
 });
 
 schema.plugin(baseModel, {
diff --git a/website/server/models/coupon.js b/website/server/models/coupon.js
index c973ffb76c..2d99143b68 100644
--- a/website/server/models/coupon.js
+++ b/website/server/models/coupon.js
@@ -11,12 +11,13 @@ import {
 } from '../libs/errors';
 
 export let schema = new mongoose.Schema({
-  _id: {type: String, default: couponCode.generate, required: true},
-  event: {type: String, enum: ['wondercon', 'google_6mo']},
-  user: {type: String, ref: 'User'},
+  _id: {$type: String, default: couponCode.generate, required: true},
+  event: {$type: String, enum: ['wondercon', 'google_6mo']},
+  user: {$type: String, ref: 'User'},
 }, {
   strict: true,
   minimize: false, // So empty objects are returned
+  typeKey: '$type', // So that we can use fields named `type`
 });
 
 schema.plugin(baseModel, {
diff --git a/website/server/models/emailUnsubscription.js b/website/server/models/emailUnsubscription.js
index 4df2ab530b..da21d264cb 100644
--- a/website/server/models/emailUnsubscription.js
+++ b/website/server/models/emailUnsubscription.js
@@ -5,7 +5,7 @@ import baseModel from '../libs/baseModel';
 // A collection used to store mailing list unsubscription for non registered email addresses
 export let schema = new mongoose.Schema({
   email: {
-    type: String,
+    $type: String,
     required: true,
     trim: true,
     lowercase: true,
@@ -14,6 +14,7 @@ export let schema = new mongoose.Schema({
 }, {
   strict: true,
   minimize: false, // So empty objects are returned
+  typeKey: '$type', // So that we can use fields named `type`
 });
 
 schema.plugin(baseModel, {
diff --git a/website/server/models/group.js b/website/server/models/group.js
index ee47849cee..1064213db0 100644
--- a/website/server/models/group.js
+++ b/website/server/models/group.js
@@ -69,31 +69,31 @@ export const MAX_CHAT_COUNT = 200;
 export const MAX_SUBBED_GROUP_CHAT_COUNT = 400;
 
 export let schema = new Schema({
-  name: {type: String, required: true},
-  summary: {type: String, maxlength: MAX_SUMMARY_SIZE_FOR_GUILDS},
+  name: {$type: String, required: true},
+  summary: {$type: String, maxlength: MAX_SUMMARY_SIZE_FOR_GUILDS},
   description: String,
-  leader: {type: String, ref: 'User', validate: [v => validator.isUUID(v), 'Invalid uuid.'], required: true},
-  type: {type: String, enum: ['guild', 'party'], required: true},
-  privacy: {type: String, enum: ['private', 'public'], default: 'private', required: true},
+  leader: {$type: String, ref: 'User', validate: [v => validator.isUUID(v), 'Invalid uuid.'], required: true},
+  type: {$type: String, enum: ['guild', 'party'], required: true},
+  privacy: {$type: String, enum: ['private', 'public'], default: 'private', required: true},
   chat: Array, // Used for backward compatibility, but messages aren't stored here
   leaderOnly: { // restrict group actions to leader (members can't do them)
-    challenges: {type: Boolean, default: false, required: true},
-    // invites: {type: Boolean, default: false, required: true},
+    challenges: {$type: Boolean, default: false, required: true},
+    // invites: {$type: Boolean, default: false, required: true},
     // Some group plans prevent members from getting gems
-    getGems: {type: Boolean, default: false},
+    getGems: {$type: Boolean, default: false},
   },
-  memberCount: {type: Number, default: 1},
-  challengeCount: {type: Number, default: 0},
-  balance: {type: Number, default: 0},
+  memberCount: {$type: Number, default: 1},
+  challengeCount: {$type: Number, default: 0},
+  balance: {$type: Number, default: 0},
   logo: String,
   leaderMessage: String,
   quest: {
     key: String,
-    active: {type: Boolean, default: false},
-    leader: {type: String, ref: 'User'},
+    active: {$type: Boolean, default: false},
+    leader: {$type: String, ref: 'User'},
     progress: {
       hp: Number,
-      collect: {type: Schema.Types.Mixed, default: () => {
+      collect: {$type: Schema.Types.Mixed, default: () => {
         return {};
       }}, // {feather: 5, ingot: 3}
       rage: Number, // limit break / "energy stored in shell", for explosion-attacks
@@ -102,34 +102,35 @@ export let schema = new Schema({
     // Shows boolean for each party-member who has accepted the quest. Eg {UUID: true, UUID: false}. Once all users click
     // 'Accept', the quest begins. If a false user waits too long, probably a good sign to prod them or boot them.
     // TODO when booting user, remove from .joined and check again if we can now start the quest
-    members: {type: Schema.Types.Mixed, default: () => {
+    members: {$type: Schema.Types.Mixed, default: () => {
       return {};
     }},
-    extra: {type: Schema.Types.Mixed, default: () => {
+    extra: {$type: Schema.Types.Mixed, default: () => {
       return {};
     }},
   },
   tasksOrder: {
-    habits: [{type: String, ref: 'Task'}],
-    dailys: [{type: String, ref: 'Task'}],
-    todos: [{type: String, ref: 'Task'}],
-    rewards: [{type: String, ref: 'Task'}],
+    habits: [{$type: String, ref: 'Task'}],
+    dailys: [{$type: String, ref: 'Task'}],
+    todos: [{$type: String, ref: 'Task'}],
+    rewards: [{$type: String, ref: 'Task'}],
   },
   purchased: {
-    plan: {type: SubscriptionPlanSchema, default: () => {
+    plan: {$type: SubscriptionPlanSchema, default: () => {
       return {};
     }},
   },
-  managers: {type: Schema.Types.Mixed, default: () => {
+  managers: {$type: Schema.Types.Mixed, default: () => {
     return {};
   }},
   categories: [{
-    slug: {type: String},
-    name: {type: String},
+    slug: {$type: String},
+    name: {$type: String},
   }],
 }, {
   strict: true,
   minimize: false, // So empty objects are returned
+  typeKey: '$type', // So that we can use fields named `type`
 });
 
 schema.plugin(baseModel, {
diff --git a/website/server/models/iapPurchaseReceipt.js b/website/server/models/iapPurchaseReceipt.js
index a03fa69a5e..6c2e339e47 100644
--- a/website/server/models/iapPurchaseReceipt.js
+++ b/website/server/models/iapPurchaseReceipt.js
@@ -5,12 +5,13 @@ import validator from 'validator';
 const Schema = mongoose.Schema;
 
 export let schema = new Schema({
-  _id: {type: String, required: true}, // Use a custom string as _id
-  consumed: {type: Boolean, default: false, required: true},
-  userId: {type: String, ref: 'User', required: true, validate: [v => validator.isUUID(v), 'Invalid uuid.']},
+  _id: {$type: String, required: true}, // Use a custom string as _id
+  consumed: {$type: Boolean, default: false, required: true},
+  userId: {$type: String, ref: 'User', required: true, validate: [v => validator.isUUID(v), 'Invalid uuid.']},
 }, {
   strict: true,
   minimize: false, // So empty objects are returned
+  typeKey: '$type', // So that we can use fields named `type`
 });
 
 schema.plugin(baseModel, {
diff --git a/website/server/models/message.js b/website/server/models/message.js
index 5e7089677c..eeecaef74e 100644
--- a/website/server/models/message.js
+++ b/website/server/models/message.js
@@ -10,22 +10,23 @@ const defaultSchema = () => ({
 
   // sender properties
   user: String, // profile name
-  contributor: {type: mongoose.Schema.Types.Mixed},
-  backer: {type: mongoose.Schema.Types.Mixed},
+  contributor: {$type: mongoose.Schema.Types.Mixed},
+  backer: {$type: mongoose.Schema.Types.Mixed},
   uuid: String, // sender uuid
-  userStyles: {type: mongoose.Schema.Types.Mixed},
+  userStyles: {$type: mongoose.Schema.Types.Mixed},
 
-  flags: {type: mongoose.Schema.Types.Mixed, default: {}},
-  flagCount: {type: Number, default: 0},
-  likes: {type: mongoose.Schema.Types.Mixed},
-  _meta: {type: mongoose.Schema.Types.Mixed},
+  flags: {$type: mongoose.Schema.Types.Mixed, default: {}},
+  flagCount: {$type: Number, default: 0},
+  likes: {$type: mongoose.Schema.Types.Mixed},
+  _meta: {$type: mongoose.Schema.Types.Mixed},
 });
 
 const chatSchema = new mongoose.Schema({
   ...defaultSchema(),
-  groupId: {type: String, ref: 'Group'},
+  groupId: {$type: String, ref: 'Group'},
 }, {
   minimize: false, // Allow for empty flags to be saved
+  typeKey: '$type', // So that we can use fields named `type`
 });
 
 chatSchema.plugin(baseModel, {
@@ -33,14 +34,15 @@ chatSchema.plugin(baseModel, {
 });
 
 const inboxSchema = new mongoose.Schema({
-  sent: {type: Boolean, default: false}, // if the owner sent this message
+  sent: {$type: Boolean, default: false}, // if the owner sent this message
   // the uuid of the user where the message is stored,
   // we store two copies of each inbox messages:
   // one for the sender and one for the receiver
-  ownerId: {type: String, ref: 'User'},
+  ownerId: {$type: String, ref: 'User'},
   ...defaultSchema(),
 }, {
   minimize: false, // Allow for empty flags to be saved
+  typeKey: '$type', // So that we can use fields named `type`
 });
 
 inboxSchema.plugin(baseModel, {
diff --git a/website/server/models/pushDevice.js b/website/server/models/pushDevice.js
index 2467f6e963..d9e7d29a55 100644
--- a/website/server/models/pushDevice.js
+++ b/website/server/models/pushDevice.js
@@ -4,12 +4,13 @@ import baseModel from '../libs/baseModel';
 const Schema = mongoose.Schema;
 
 export let schema = new Schema({
-  regId: {type: String, required: true},
-  type: {type: String, required: true, enum: ['ios', 'android']},
+  regId: {$type: String, required: true},
+  type: {$type: String, required: true, enum: ['ios', 'android']},
 }, {
   strict: true,
   minimize: false, // So empty objects are returned
   _id: false,
+  typeKey: '$type', // So that we can use a field named `type`
 });
 
 schema.plugin(baseModel, {
diff --git a/website/server/models/subscriptionPlan.js b/website/server/models/subscriptionPlan.js
index 86609cfa44..c26f03bd6a 100644
--- a/website/server/models/subscriptionPlan.js
+++ b/website/server/models/subscriptionPlan.js
@@ -5,30 +5,31 @@ import validator from 'validator';
 export let schema = new mongoose.Schema({
   planId: String,
   subscriptionId: String,
-  owner: {type: String, ref: 'User', validate: [v => validator.isUUID(v), 'Invalid uuid.']},
-  quantity: {type: Number, default: 1},
+  owner: {$type: String, ref: 'User', validate: [v => validator.isUUID(v), 'Invalid uuid.']},
+  quantity: {$type: Number, default: 1},
   paymentMethod: String, // enum: ['Paypal', 'Stripe', 'Gift', 'Amazon Payments', 'Google', '']}
   customerId: String, // Billing Agreement Id in case of Amazon Payments
   dateCreated: Date,
   dateTerminated: Date,
   dateUpdated: Date,
-  extraMonths: {type: Number, default: 0},
-  gemsBought: {type: Number, default: 0},
-  mysteryItems: {type: Array, default: () => []},
+  extraMonths: {$type: Number, default: 0},
+  gemsBought: {$type: Number, default: 0},
+  mysteryItems: {$type: Array, default: () => []},
   lastBillingDate: Date, // Used only for Amazon Payments to keep track of billing date
   additionalData: mongoose.Schema.Types.Mixed, // Example for Google: {'receipt': 'serialized receipt json', 'signature': 'signature string'}
   nextPaymentProcessing: Date, // indicates when the queue server should process this subscription again.
   nextBillingDate: Date, // Next time google will bill this user.
   consecutive: {
-    count: {type: Number, default: 0},
-    offset: {type: Number, default: 0}, // when gifted subs, offset++ for each month. offset-- each new-month (cron). count doesn't ++ until offset==0
-    gemCapExtra: {type: Number, default: 0},
-    trinkets: {type: Number, default: 0},
+    count: {$type: Number, default: 0},
+    offset: {$type: Number, default: 0}, // when gifted subs, offset++ for each month. offset-- each new-month (cron). count doesn't ++ until offset==0
+    gemCapExtra: {$type: Number, default: 0},
+    trinkets: {$type: Number, default: 0},
   },
 }, {
   strict: true,
   minimize: false, // So empty objects are returned
   _id: false,
+  typeKey: '$type', // So that we can use fields named `type`
 });
 
 schema.plugin(baseModel, {
diff --git a/website/server/models/tag.js b/website/server/models/tag.js
index 659b50f1d7..5e96037656 100644
--- a/website/server/models/tag.js
+++ b/website/server/models/tag.js
@@ -7,18 +7,19 @@ const Schema = mongoose.Schema;
 
 export let schema = new Schema({
   id: {
-    type: String,
+    $type: String,
     default: uuid,
     validate: [v => validator.isUUID(v), 'Invalid uuid.'],
     required: true,
   },
-  name: {type: String, required: true},
-  challenge: {type: String},
-  group: {type: String},
+  name: {$type: String, required: true},
+  challenge: {$type: String},
+  group: {$type: String},
 }, {
   strict: true,
   minimize: false, // So empty objects are returned
   _id: false, // use id instead of _id
+  typeKey: '$type', // So that we can use fields named `type`
 });
 
 schema.plugin(baseModel, {
diff --git a/website/server/models/task.js b/website/server/models/task.js
index 55dcf72499..d1fbe17970 100644
--- a/website/server/models/task.js
+++ b/website/server/models/task.js
@@ -16,6 +16,7 @@ let discriminatorOptions = {
 let subDiscriminatorOptions = _.defaults(_.cloneDeep(discriminatorOptions), {
   _id: false,
   minimize: false, // So empty objects are returned
+  typeKey: '$type', // So that we can use fields named `type`
 });
 
 export let tasksTypes = ['habit', 'daily', 'todo', 'reward'];
@@ -39,11 +40,11 @@ export const taskIsGroupOrChallengeQuery = {
 // Important
 // When something changes here remember to update the client side model at common/script/libs/taskDefaults
 export let TaskSchema = new Schema({
-  type: {type: String, enum: tasksTypes, required: true, default: tasksTypes[0]},
-  text: {type: String, required: true},
-  notes: {type: String, default: ''},
+  type: {$type: String, enum: tasksTypes, required: true, default: tasksTypes[0]},
+  text: {$type: String, required: true},
+  notes: {$type: String, default: ''},
   alias: {
-    type: String,
+    $type: String,
     match: [/^[a-zA-Z0-9-_]+$/, 'Task short names can only contain alphanumeric characters, underscores and dashes.'],
     validate: [{
       validator () {
@@ -75,12 +76,12 @@ export let TaskSchema = new Schema({
     }],
   },
   tags: [{
-    type: String,
+    $type: String,
     validate: [v => validator.isUUID(v), 'Invalid uuid.'],
   }],
-  value: {type: Number, default: 0, required: true}, // redness or cost for rewards Required because it must be settable (for rewards)
+  value: {$type: Number, default: 0, required: true}, // redness or cost for rewards Required because it must be settable (for rewards)
   priority: {
-    type: Number,
+    $type: Number,
     default: 1,
     required: true,
     validate: [
@@ -88,42 +89,43 @@ export let TaskSchema = new Schema({
       'Valid priority values are 0.1, 1, 1.5, 2.',
     ],
   },
-  attribute: {type: String, default: 'str', enum: ['str', 'con', 'int', 'per']},
-  userId: {type: String, ref: 'User', validate: [v => validator.isUUID(v), 'Invalid uuid.']}, // When not set it belongs to a challenge
+  attribute: {$type: String, default: 'str', enum: ['str', 'con', 'int', 'per']},
+  userId: {$type: String, ref: 'User', validate: [v => validator.isUUID(v), 'Invalid uuid.']}, // When not set it belongs to a challenge
 
   challenge: {
-    shortName: {type: String},
-    id: {type: String, ref: 'Challenge', validate: [v => validator.isUUID(v), 'Invalid uuid.']}, // When set (and userId not set) it's the original task
-    taskId: {type: String, ref: 'Task', validate: [v => validator.isUUID(v), 'Invalid uuid.']}, // When not set but challenge.id defined it's the original task
-    broken: {type: String, enum: ['CHALLENGE_DELETED', 'TASK_DELETED', 'UNSUBSCRIBED', 'CHALLENGE_CLOSED', 'CHALLENGE_TASK_NOT_FOUND']}, // CHALLENGE_TASK_NOT_FOUND comes from v3 migration
+    shortName: {$type: String},
+    id: {$type: String, ref: 'Challenge', validate: [v => validator.isUUID(v), 'Invalid uuid.']}, // When set (and userId not set) it's the original task
+    taskId: {$type: String, ref: 'Task', validate: [v => validator.isUUID(v), 'Invalid uuid.']}, // When not set but challenge.id defined it's the original task
+    broken: {$type: String, enum: ['CHALLENGE_DELETED', 'TASK_DELETED', 'UNSUBSCRIBED', 'CHALLENGE_CLOSED', 'CHALLENGE_TASK_NOT_FOUND']}, // CHALLENGE_TASK_NOT_FOUND comes from v3 migration
     winner: String, // user.profile.name of the winner
   },
 
   group: {
-    id: {type: String, ref: 'Group', validate: [v => validator.isUUID(v), 'Invalid uuid.']},
-    broken: {type: String, enum: ['GROUP_DELETED', 'TASK_DELETED', 'UNSUBSCRIBED']},
-    assignedUsers: [{type: String, ref: 'User', validate: [v => validator.isUUID(v), 'Invalid uuid.']}],
-    taskId: {type: String, ref: 'Task', validate: [v => validator.isUUID(v), 'Invalid uuid.']},
+    id: {$type: String, ref: 'Group', validate: [v => validator.isUUID(v), 'Invalid uuid.']},
+    broken: {$type: String, enum: ['GROUP_DELETED', 'TASK_DELETED', 'UNSUBSCRIBED']},
+    assignedUsers: [{$type: String, ref: 'User', validate: [v => validator.isUUID(v), 'Invalid uuid.']}],
+    taskId: {$type: String, ref: 'Task', validate: [v => validator.isUUID(v), 'Invalid uuid.']},
     approval: {
-      required: {type: Boolean, default: false},
-      approved: {type: Boolean, default: false},
-      dateApproved: {type: Date},
-      approvingUser: {type: String, ref: 'User', validate: [v => validator.isUUID(v), 'Invalid uuid.']},
-      requested: {type: Boolean, default: false},
-      requestedDate: {type: Date},
+      required: {$type: Boolean, default: false},
+      approved: {$type: Boolean, default: false},
+      dateApproved: {$type: Date},
+      approvingUser: {$type: String, ref: 'User', validate: [v => validator.isUUID(v), 'Invalid uuid.']},
+      requested: {$type: Boolean, default: false},
+      requestedDate: {$type: Date},
     },
-    sharedCompletion: {type: String, enum: _.values(SHARED_COMPLETION), default: SHARED_COMPLETION.default},
+    sharedCompletion: {$type: String, enum: _.values(SHARED_COMPLETION), default: SHARED_COMPLETION.default},
   },
 
   reminders: [{
     _id: false,
-    id: {type: String, validate: [v => validator.isUUID(v), 'Invalid uuid.'], default: shared.uuid, required: true},
-    startDate: {type: Date},
-    time: {type: Date, required: true},
+    id: {$type: String, validate: [v => validator.isUUID(v), 'Invalid uuid.'], default: shared.uuid, required: true},
+    startDate: {$type: Date},
+    time: {$type: Date, required: true},
   }],
 }, _.defaults({
   minimize: false, // So empty objects are returned
   strict: true,
+  typeKey: '$type', // So that we can use fields named `type`
 }, discriminatorOptions));
 
 TaskSchema.plugin(baseModel, {
@@ -258,32 +260,32 @@ let habitDailySchema = () => {
 // dailys and todos shared fields
 let dailyTodoSchema = () => {
   return {
-    completed: {type: Boolean, default: false},
+    completed: {$type: Boolean, default: false},
     // Checklist fields (dailies and todos)
-    collapseChecklist: {type: Boolean, default: false},
+    collapseChecklist: {$type: Boolean, default: false},
     checklist: [{
-      completed: {type: Boolean, default: false},
-      text: {type: String, required: false, default: ''}, // required:false because it can be empty on creation
+      completed: {$type: Boolean, default: false},
+      text: {$type: String, required: false, default: ''}, // required:false because it can be empty on creation
       _id: false,
-      id: {type: String, default: shared.uuid, required: true, validate: [v => validator.isUUID(v), 'Invalid uuid.']},
-      linkId: {type: String},
+      id: {$type: String, default: shared.uuid, required: true, validate: [v => validator.isUUID(v), 'Invalid uuid.']},
+      linkId: {$type: String},
     }],
   };
 };
 
 export let HabitSchema = new Schema(_.defaults({
-  up: {type: Boolean, default: true},
-  down: {type: Boolean, default: true},
-  counterUp: {type: Number, default: 0},
-  counterDown: {type: Number, default: 0},
-  frequency: {type: String, default: 'daily', enum: ['daily', 'weekly', 'monthly']},
+  up: {$type: Boolean, default: true},
+  down: {$type: Boolean, default: true},
+  counterUp: {$type: Number, default: 0},
+  counterDown: {$type: Number, default: 0},
+  frequency: {$type: String, default: 'daily', enum: ['daily', 'weekly', 'monthly']},
 }, habitDailySchema()), subDiscriminatorOptions);
 export let habit = Task.discriminator('habit', HabitSchema);
 
 export let DailySchema = new Schema(_.defaults({
-  frequency: {type: String, default: 'weekly', enum: ['daily', 'weekly', 'monthly', 'yearly']},
+  frequency: {$type: String, default: 'weekly', enum: ['daily', 'weekly', 'monthly', 'yearly']},
   everyX: {
-    type: Number,
+    $type: Number,
     default: 1,
     validate: [
       (val) => val % 1 === 0 && val >= 0 && val <= 9999,
@@ -291,33 +293,33 @@ export let DailySchema = new Schema(_.defaults({
     ],
   },
   startDate: {
-    type: Date,
+    $type: Date,
     default () {
       return moment().startOf('day').toDate();
     },
     required: true,
   },
   repeat: { // used only for 'weekly' frequency,
-    m: {type: Boolean, default: true},
-    t: {type: Boolean, default: true},
-    w: {type: Boolean, default: true},
-    th: {type: Boolean, default: true},
-    f: {type: Boolean, default: true},
-    s: {type: Boolean, default: true},
-    su: {type: Boolean, default: true},
+    m: {$type: Boolean, default: true},
+    t: {$type: Boolean, default: true},
+    w: {$type: Boolean, default: true},
+    th: {$type: Boolean, default: true},
+    f: {$type: Boolean, default: true},
+    s: {$type: Boolean, default: true},
+    su: {$type: Boolean, default: true},
   },
-  streak: {type: Number, default: 0},
-  daysOfMonth: {type: [Number], default: []}, // Days of the month that the daily should repeat on
-  weeksOfMonth: {type: [Number], default: []}, // Weeks of the month that the daily should repeat on
-  isDue: {type: Boolean},
-  nextDue: [{type: String}],
-  yesterDaily: {type: Boolean, default: true, required: true},
+  streak: {$type: Number, default: 0},
+  daysOfMonth: {$type: [Number], default: []}, // Days of the month that the daily should repeat on
+  weeksOfMonth: {$type: [Number], default: []}, // Weeks of the month that the daily should repeat on
+  isDue: {$type: Boolean},
+  nextDue: [{$type: String}],
+  yesterDaily: {$type: Boolean, default: true, required: true},
 }, habitDailySchema(), dailyTodoSchema()), subDiscriminatorOptions);
 export let daily = Task.discriminator('daily', DailySchema);
 
 export let TodoSchema = new Schema(_.defaults({
   dateCompleted: Date,
-  // TODO we're getting parse errors, people have stored as "today" and "3/13". Need to run a migration & put this back to type: Date see http://stackoverflow.com/questions/1353684/detecting-an-invalid-date-date-instance-in-javascript
+  // TODO we're getting parse errors, people have stored as "today" and "3/13". Need to run a migration & put this back to $type: Date see http://stackoverflow.com/questions/1353684/detecting-an-invalid-date-date-instance-in-javascript
   date: String, // due date for todos
 }, dailyTodoSchema()), subDiscriminatorOptions);
 export let todo = Task.discriminator('todo', TodoSchema);
diff --git a/website/server/models/user/schema.js b/website/server/models/user/schema.js
index 4ce701ecbe..3909c0dd53 100644
--- a/website/server/models/user/schema.js
+++ b/website/server/models/user/schema.js
@@ -19,21 +19,21 @@ const RESTRICTED_EMAIL_DOMAINS = Object.freeze(['habitica.com', 'habitrpg.com'])
 // User schema definition
 let schema = new Schema({
   apiToken: {
-    type: String,
+    $type: String,
     default: shared.uuid,
   },
 
   auth: {
     blocked: Boolean,
-    facebook: {type: Schema.Types.Mixed, default: () => {
+    facebook: {$type: Schema.Types.Mixed, default: () => {
       return {};
     }},
-    google: {type: Schema.Types.Mixed, default: () => {
+    google: {$type: Schema.Types.Mixed, default: () => {
       return {};
     }},
     local: {
       email: {
-        type: String,
+        $type: String,
         validate: [{
           validator: (v) => validator.isEmail(v),
           message: shared.i18n.t('invalidEmail'),
@@ -49,14 +49,14 @@ let schema = new Schema({
         }],
       },
       username: {
-        type: String,
+        $type: String,
       },
       // Store a lowercase version of username to check for duplicates
       lowerCaseUsername: String,
       hashed_password: String, // eslint-disable-line camelcase
       // Legacy password are hashed with SHA1, new ones with bcrypt
       passwordHashMethod: {
-        type: String,
+        $type: String,
         enum: ['bcrypt', 'sha1'],
       },
       salt: String, // Salt for SHA1 encrypted passwords, not stored for bcrypt,
@@ -64,22 +64,22 @@ let schema = new Schema({
       passwordResetCode: String,
     },
     timestamps: {
-      created: {type: Date, default: Date.now},
-      loggedin: {type: Date, default: Date.now},
+      created: {$type: Date, default: Date.now},
+      loggedin: {$type: Date, default: Date.now},
     },
   },
   // We want to know *every* time an object updates. Mongoose uses __v to designate when an object contains arrays which
   // have been updated (http://goo.gl/gQLz41), but we want *every* update
-  _v: { type: Number, default: 0 },
+  _v: { $type: Number, default: 0 },
   migration: String,
   achievements: {
     originalUser: Boolean,
     habitSurveys: Number,
     ultimateGearSets: {
-      healer: {type: Boolean, default: false},
-      wizard: {type: Boolean, default: false},
-      rogue: {type: Boolean, default: false},
-      warrior: {type: Boolean, default: false},
+      healer: {$type: Boolean, default: false},
+      wizard: {$type: Boolean, default: false},
+      rogue: {$type: Boolean, default: false},
+      warrior: {$type: Boolean, default: false},
     },
     beastMaster: Boolean,
     beastMasterCount: Number,
@@ -94,12 +94,12 @@ let schema = new Schema({
     seafoam: Number,
     streak: Number,
     challenges: Array,
-    quests: {type: Schema.Types.Mixed, default: () => {
+    quests: {$type: Schema.Types.Mixed, default: () => {
       return {};
     }},
     rebirths: Number,
     rebirthLevel: Number,
-    perfect: {type: Number, default: 0},
+    perfect: {$type: Number, default: 0},
     habitBirthdays: Number,
     valentine: Number,
     nye: Number,
@@ -129,7 +129,7 @@ let schema = new Schema({
   contributor: {
     // 1-9, see https://trello.com/c/wkFzONhE/277-contributor-gear https://github.com/HabitRPG/habitica/issues/3801
     level: {
-      type: Number,
+      $type: Number,
       min: 0,
       max: 9,
     },
@@ -142,106 +142,106 @@ let schema = new Schema({
     critical: String,
   },
 
-  balance: {type: Number, default: 0},
+  balance: {$type: Number, default: 0},
 
   purchased: {
-    ads: {type: Boolean, default: false},
+    ads: {$type: Boolean, default: false},
     // eg, {skeleton: true, pumpkin: true, eb052b: true}
-    skin: {type: Schema.Types.Mixed, default: () => {
+    skin: {$type: Schema.Types.Mixed, default: () => {
       return {};
     }},
-    hair: {type: Schema.Types.Mixed, default: () => {
+    hair: {$type: Schema.Types.Mixed, default: () => {
       return {};
     }},
-    shirt: {type: Schema.Types.Mixed, default: () => {
+    shirt: {$type: Schema.Types.Mixed, default: () => {
       return {};
     }},
-    background: {type: Schema.Types.Mixed, default: () => {
+    background: {$type: Schema.Types.Mixed, default: () => {
       return {};
     }},
-    txnCount: {type: Number, default: 0},
+    txnCount: {$type: Number, default: 0},
     mobileChat: Boolean,
-    plan: {type: SubscriptionPlanSchema, default: () => {
+    plan: {$type: SubscriptionPlanSchema, default: () => {
       return {};
     }},
   },
 
   flags: {
-    customizationsNotification: {type: Boolean, default: false},
-    showTour: {type: Boolean, default: true},
+    customizationsNotification: {$type: Boolean, default: false},
+    showTour: {$type: Boolean, default: true},
     tour: {
       // -1 indicates "uninitiated", -2 means "complete", any other number is the current tour step (0-index)
-      intro: {type: Number, default: -1},
-      classes: {type: Number, default: -1},
-      stats: {type: Number, default: -1},
-      tavern: {type: Number, default: -1},
-      party: {type: Number, default: -1},
-      guilds: {type: Number, default: -1},
-      challenges: {type: Number, default: -1},
-      market: {type: Number, default: -1},
-      pets: {type: Number, default: -1},
-      mounts: {type: Number, default: -1},
-      hall: {type: Number, default: -1},
-      equipment: {type: Number, default: -1},
+      intro: {$type: Number, default: -1},
+      classes: {$type: Number, default: -1},
+      stats: {$type: Number, default: -1},
+      tavern: {$type: Number, default: -1},
+      party: {$type: Number, default: -1},
+      guilds: {$type: Number, default: -1},
+      challenges: {$type: Number, default: -1},
+      market: {$type: Number, default: -1},
+      pets: {$type: Number, default: -1},
+      mounts: {$type: Number, default: -1},
+      hall: {$type: Number, default: -1},
+      equipment: {$type: Number, default: -1},
     },
     tutorial: {
       common: {
-        habits: {type: Boolean, default: false},
-        dailies: {type: Boolean, default: false},
-        todos: {type: Boolean, default: false},
-        rewards: {type: Boolean, default: false},
-        party: {type: Boolean, default: false},
-        pets: {type: Boolean, default: false},
-        gems: {type: Boolean, default: false},
-        skills: {type: Boolean, default: false},
-        classes: {type: Boolean, default: false},
-        tavern: {type: Boolean, default: false},
-        equipment: {type: Boolean, default: false},
-        items: {type: Boolean, default: false},
-        mounts: {type: Boolean, default: false},
-        inbox: {type: Boolean, default: false},
-        stats: {type: Boolean, default: false},
+        habits: {$type: Boolean, default: false},
+        dailies: {$type: Boolean, default: false},
+        todos: {$type: Boolean, default: false},
+        rewards: {$type: Boolean, default: false},
+        party: {$type: Boolean, default: false},
+        pets: {$type: Boolean, default: false},
+        gems: {$type: Boolean, default: false},
+        skills: {$type: Boolean, default: false},
+        classes: {$type: Boolean, default: false},
+        tavern: {$type: Boolean, default: false},
+        equipment: {$type: Boolean, default: false},
+        items: {$type: Boolean, default: false},
+        mounts: {$type: Boolean, default: false},
+        inbox: {$type: Boolean, default: false},
+        stats: {$type: Boolean, default: false},
       },
       ios: {
-        addTask: {type: Boolean, default: false},
-        editTask: {type: Boolean, default: false},
-        deleteTask: {type: Boolean, default: false},
-        filterTask: {type: Boolean, default: false},
-        groupPets: {type: Boolean, default: false},
-        inviteParty: {type: Boolean, default: false},
-        reorderTask: {type: Boolean, default: false},
+        addTask: {$type: Boolean, default: false},
+        editTask: {$type: Boolean, default: false},
+        deleteTask: {$type: Boolean, default: false},
+        filterTask: {$type: Boolean, default: false},
+        groupPets: {$type: Boolean, default: false},
+        inviteParty: {$type: Boolean, default: false},
+        reorderTask: {$type: Boolean, default: false},
       },
     },
-    dropsEnabled: {type: Boolean, default: false},
-    itemsEnabled: {type: Boolean, default: false},
-    newStuff: {type: Boolean, default: false},
-    rewrite: {type: Boolean, default: true},
-    classSelected: {type: Boolean, default: false},
+    dropsEnabled: {$type: Boolean, default: false},
+    itemsEnabled: {$type: Boolean, default: false},
+    newStuff: {$type: Boolean, default: false},
+    rewrite: {$type: Boolean, default: true},
+    classSelected: {$type: Boolean, default: false},
     mathUpdates: Boolean,
-    rebirthEnabled: {type: Boolean, default: false},
-    levelDrops: {type: Schema.Types.Mixed, default: () => {
+    rebirthEnabled: {$type: Boolean, default: false},
+    levelDrops: {$type: Schema.Types.Mixed, default: () => {
       return {};
     }},
     chatRevoked: Boolean,
     // Used to track the status of recapture emails sent to each user,
     // can be 0 - no email sent - 1, 2, 3 or 4 - 4 means no more email will be sent to the user
-    recaptureEmailsPhase: {type: Number, default: 0},
+    recaptureEmailsPhase: {$type: Number, default: 0},
     // Needed to track the tip to send inside the email
-    weeklyRecapEmailsPhase: {type: Number, default: 0},
+    weeklyRecapEmailsPhase: {$type: Number, default: 0},
     // Used to track when the next weekly recap should be sent
-    lastWeeklyRecap: {type: Date, default: Date.now},
+    lastWeeklyRecap: {$type: Date, default: Date.now},
     // Used to enable weekly recap emails as users login
     lastWeeklyRecapDiscriminator: Boolean,
     onboardingEmailsPhase: String, // Keep track of the latest onboarding email sent
-    communityGuidelinesAccepted: {type: Boolean, default: false},
-    cronCount: {type: Number, default: 0},
-    welcomed: {type: Boolean, default: false},
-    armoireEnabled: {type: Boolean, default: true},
-    armoireOpened: {type: Boolean, default: false},
-    armoireEmpty: {type: Boolean, default: false},
-    cardReceived: {type: Boolean, default: false},
-    warnedLowHealth: {type: Boolean, default: false},
-    verifiedUsername: {type: Boolean, default: false},
+    communityGuidelinesAccepted: {$type: Boolean, default: false},
+    cronCount: {$type: Number, default: 0},
+    welcomed: {$type: Boolean, default: false},
+    armoireEnabled: {$type: Boolean, default: true},
+    armoireOpened: {$type: Boolean, default: false},
+    armoireEmpty: {$type: Boolean, default: false},
+    cardReceived: {$type: Boolean, default: false},
+    warnedLowHealth: {$type: Boolean, default: false},
+    verifiedUsername: {$type: Boolean, default: false},
   },
 
   history: {
@@ -252,7 +252,7 @@ let schema = new Schema({
   items: {
     gear: {
       owned: _.transform(shared.content.gear.flat, (m, v) => {
-        m[v.key] = {type: Boolean};
+        m[v.key] = {$type: Boolean};
         if (v.key.match(/(armor|head|shield)_warrior_0/) || v.gearSet === 'glasses' || v.gearSet === 'headband') {
           m[v.key].default = true;
         }
@@ -260,9 +260,9 @@ let schema = new Schema({
 
       equipped: {
         weapon: String,
-        armor: {type: String, default: 'armor_base_0'},
-        head: {type: String, default: 'head_base_0'},
-        shield: {type: String, default: 'shield_base_0'},
+        armor: {$type: String, default: 'armor_base_0'},
+        head: {$type: String, default: 'head_base_0'},
+        shield: {$type: String, default: 'shield_base_0'},
         back: String,
         headAccessory: String,
         eyewear: String,
@@ -270,9 +270,9 @@ let schema = new Schema({
       },
       costume: {
         weapon: String,
-        armor: {type: String, default: 'armor_base_0'},
-        head: {type: String, default: 'head_base_0'},
-        shield: {type: String, default: 'shield_base_0'},
+        armor: {$type: String, default: 'armor_base_0'},
+        head: {$type: String, default: 'head_base_0'},
+        shield: {$type: String, default: 'shield_base_0'},
         back: String,
         headAccessory: String,
         eyewear: String,
@@ -281,25 +281,25 @@ let schema = new Schema({
     },
 
     special: {
-      snowball: {type: Number, default: 0},
-      spookySparkles: {type: Number, default: 0},
-      shinySeed: {type: Number, default: 0},
-      seafoam: {type: Number, default: 0},
-      valentine: {type: Number, default: 0},
+      snowball: {$type: Number, default: 0},
+      spookySparkles: {$type: Number, default: 0},
+      shinySeed: {$type: Number, default: 0},
+      seafoam: {$type: Number, default: 0},
+      valentine: {$type: Number, default: 0},
       valentineReceived: Array, // array of strings, by sender name
-      nye: {type: Number, default: 0},
+      nye: {$type: Number, default: 0},
       nyeReceived: Array,
-      greeting: {type: Number, default: 0},
+      greeting: {$type: Number, default: 0},
       greetingReceived: Array,
-      thankyou: {type: Number, default: 0},
+      thankyou: {$type: Number, default: 0},
       thankyouReceived: Array,
-      birthday: {type: Number, default: 0},
+      birthday: {$type: Number, default: 0},
       birthdayReceived: Array,
-      congrats: {type: Number, default: 0},
+      congrats: {$type: Number, default: 0},
       congratsReceived: Array,
-      getwell: {type: Number, default: 0},
+      getwell: {$type: Number, default: 0},
       getwellReceived: Array,
-      goodluck: {type: Number, default: 0},
+      goodluck: {$type: Number, default: 0},
       goodluckReceived: Array,
     },
 
@@ -361,44 +361,44 @@ let schema = new Schema({
     quests: _.transform(shared.content.quests, (m, v, k) => m[k] = Number),
 
     lastDrop: {
-      date: {type: Date, default: Date.now},
-      count: {type: Number, default: 0},
+      date: {$type: Date, default: Date.now},
+      count: {$type: Number, default: 0},
     },
   },
 
-  lastCron: {type: Date, default: Date.now},
-  _cronSignature: {type: String, default: 'NOT_RUNNING'}, // Private property used to avoid double cron
+  lastCron: {$type: Date, default: Date.now},
+  _cronSignature: {$type: String, default: 'NOT_RUNNING'}, // Private property used to avoid double cron
 
   // {GROUP_ID: Boolean}, represents whether they have unseen chat messages
-  newMessages: {type: Schema.Types.Mixed, default: () => {
+  newMessages: {$type: Schema.Types.Mixed, default: () => {
     return {};
   }},
 
-  challenges: [{type: String, ref: 'Challenge', validate: [v => validator.isUUID(v), 'Invalid uuid.']}],
+  challenges: [{$type: String, ref: 'Challenge', validate: [v => validator.isUUID(v), 'Invalid uuid.']}],
 
   invitations: {
     // Using an array without validation because otherwise mongoose treat this as a subdocument and applies _id by default
     // Schema is (id, name, inviter, publicGuild)
     // TODO one way to fix is http://mongoosejs.com/docs/guide.html#_id
-    guilds: {type: Array, default: () => []},
+    guilds: {$type: Array, default: () => []},
     // Using a Mixed type because otherwise user.invitations.party = {} // to reset invitation, causes validation to fail TODO
     // schema is the same as for guild invitations (id, name, inviter)
-    party: {type: Schema.Types.Mixed, default: () => {
+    party: {$type: Schema.Types.Mixed, default: () => {
       return {};
     }},
     parties: [{
       id: {
-        type: String,
+        $type: String,
         ref: 'Group',
         required: true,
         validate: [v => validator.isUUID(v), 'Invalid uuid.'],
       },
       name: {
-        type: String,
+        $type: String,
         required: true,
       },
       inviter: {
-        type: String,
+        $type: String,
         ref: 'User',
         required: true,
         validate: [v => validator.isUUID(v), 'Invalid uuid.'],
@@ -406,105 +406,105 @@ let schema = new Schema({
     }],
   },
 
-  guilds: [{type: String, ref: 'Group', validate: [v => validator.isUUID(v), 'Invalid uuid.']}],
+  guilds: [{$type: String, ref: 'Group', validate: [v => validator.isUUID(v), 'Invalid uuid.']}],
 
   party: {
-    _id: {type: String, validate: [v => validator.isUUID(v), 'Invalid uuid.'], ref: 'Group'},
-    order: {type: String, default: 'level'},
-    orderAscending: {type: String, default: 'ascending'},
+    _id: {$type: String, validate: [v => validator.isUUID(v), 'Invalid uuid.'], ref: 'Group'},
+    order: {$type: String, default: 'level'},
+    orderAscending: {$type: String, default: 'ascending'},
     quest: {
       key: String,
       progress: {
-        up: {type: Number, default: 0},
-        down: {type: Number, default: 0},
-        collect: {type: Schema.Types.Mixed, default: () => {
+        up: {$type: Number, default: 0},
+        down: {$type: Number, default: 0},
+        collect: {$type: Schema.Types.Mixed, default: () => {
           return {};
         }},
-        collectedItems: {type: Number, default: 0},
+        collectedItems: {$type: Number, default: 0},
       },
       completed: String, // When quest is done, we move it from key => completed, and it's a one-time flag (for modal) that they unset by clicking "ok" in browser
-      RSVPNeeded: {type: Boolean, default: false}, // Set to true when invite is pending, set to false when quest invite is accepted or rejected, quest starts, or quest is cancelled
+      RSVPNeeded: {$type: Boolean, default: false}, // Set to true when invite is pending, set to false when quest invite is accepted or rejected, quest starts, or quest is cancelled
     },
   },
   preferences: {
-    dayStart: {type: Number, default: 0, min: 0, max: 23},
-    size: {type: String, enum: ['broad', 'slim'], default: 'slim'},
+    dayStart: {$type: Number, default: 0, min: 0, max: 23},
+    size: {$type: String, enum: ['broad', 'slim'], default: 'slim'},
     hair: {
-      color: {type: String, default: 'red'},
-      base: {type: Number, default: 3},
-      bangs: {type: Number, default: 1},
-      beard: {type: Number, default: 0},
-      mustache: {type: Number, default: 0},
-      flower: {type: Number, default: 1},
+      color: {$type: String, default: 'red'},
+      base: {$type: Number, default: 3},
+      bangs: {$type: Number, default: 1},
+      beard: {$type: Number, default: 0},
+      mustache: {$type: Number, default: 0},
+      flower: {$type: Number, default: 1},
     },
-    hideHeader: {type: Boolean, default: false},
-    skin: {type: String, default: '915533'},
-    shirt: {type: String, default: 'blue'},
-    timezoneOffset: {type: Number, default: 0},
-    sound: {type: String, default: 'rosstavoTheme', enum: ['off', ...shared.content.audioThemes]},
-    chair: {type: String, default: 'none'},
+    hideHeader: {$type: Boolean, default: false},
+    skin: {$type: String, default: '915533'},
+    shirt: {$type: String, default: 'blue'},
+    timezoneOffset: {$type: Number, default: 0},
+    sound: {$type: String, default: 'rosstavoTheme', enum: ['off', ...shared.content.audioThemes]},
+    chair: {$type: String, default: 'none'},
     timezoneOffsetAtLastCron: Number,
     language: String,
     automaticAllocation: Boolean,
-    allocationMode: {type: String, enum: ['flat', 'classbased', 'taskbased'], default: 'flat'},
-    autoEquip: {type: Boolean, default: true},
+    allocationMode: {$type: String, enum: ['flat', 'classbased', 'taskbased'], default: 'flat'},
+    autoEquip: {$type: Boolean, default: true},
     costume: Boolean,
-    dateFormat: {type: String, enum: ['MM/dd/yyyy', 'dd/MM/yyyy', 'yyyy/MM/dd'], default: 'MM/dd/yyyy'},
-    sleep: {type: Boolean, default: false},
-    stickyHeader: {type: Boolean, default: true},
-    disableClasses: {type: Boolean, default: false},
-    newTaskEdit: {type: Boolean, default: false},
-    dailyDueDefaultView: {type: Boolean, default: false},
-    advancedCollapsed: {type: Boolean, default: false},
-    toolbarCollapsed: {type: Boolean, default: false},
-    reverseChatOrder: {type: Boolean, default: false},
+    dateFormat: {$type: String, enum: ['MM/dd/yyyy', 'dd/MM/yyyy', 'yyyy/MM/dd'], default: 'MM/dd/yyyy'},
+    sleep: {$type: Boolean, default: false},
+    stickyHeader: {$type: Boolean, default: true},
+    disableClasses: {$type: Boolean, default: false},
+    newTaskEdit: {$type: Boolean, default: false},
+    dailyDueDefaultView: {$type: Boolean, default: false},
+    advancedCollapsed: {$type: Boolean, default: false},
+    toolbarCollapsed: {$type: Boolean, default: false},
+    reverseChatOrder: {$type: Boolean, default: false},
     background: String,
-    displayInviteToPartyWhenPartyIs1: {type: Boolean, default: true},
-    webhooks: {type: Schema.Types.Mixed, default: () => {
+    displayInviteToPartyWhenPartyIs1: {$type: Boolean, default: true},
+    webhooks: {$type: Schema.Types.Mixed, default: () => {
       return {};
     }},
     // For the following fields make sure to use strict comparison when searching for falsey values (=== false)
     // As users who didn't login after these were introduced may have them undefined/null
     emailNotifications: {
-      unsubscribeFromAll: {type: Boolean, default: false},
-      newPM: {type: Boolean, default: true},
-      kickedGroup: {type: Boolean, default: true},
-      wonChallenge: {type: Boolean, default: true},
-      giftedGems: {type: Boolean, default: true},
-      giftedSubscription: {type: Boolean, default: true},
-      invitedParty: {type: Boolean, default: true},
-      invitedGuild: {type: Boolean, default: true},
-      questStarted: {type: Boolean, default: true},
-      invitedQuest: {type: Boolean, default: true},
-      // remindersToLogin: {type: Boolean, default: true},
+      unsubscribeFromAll: {$type: Boolean, default: false},
+      newPM: {$type: Boolean, default: true},
+      kickedGroup: {$type: Boolean, default: true},
+      wonChallenge: {$type: Boolean, default: true},
+      giftedGems: {$type: Boolean, default: true},
+      giftedSubscription: {$type: Boolean, default: true},
+      invitedParty: {$type: Boolean, default: true},
+      invitedGuild: {$type: Boolean, default: true},
+      questStarted: {$type: Boolean, default: true},
+      invitedQuest: {$type: Boolean, default: true},
+      // remindersToLogin: {$type: Boolean, default: true},
       // importantAnnouncements are in fact the recapture emails
-      importantAnnouncements: {type: Boolean, default: true},
-      weeklyRecaps: {type: Boolean, default: true},
-      onboarding: {type: Boolean, default: true},
+      importantAnnouncements: {$type: Boolean, default: true},
+      weeklyRecaps: {$type: Boolean, default: true},
+      onboarding: {$type: Boolean, default: true},
     },
     pushNotifications: {
-      unsubscribeFromAll: {type: Boolean, default: false},
-      newPM: {type: Boolean, default: true},
-      wonChallenge: {type: Boolean, default: true},
-      giftedGems: {type: Boolean, default: true},
-      giftedSubscription: {type: Boolean, default: true},
-      invitedParty: {type: Boolean, default: true},
-      invitedGuild: {type: Boolean, default: true},
-      questStarted: {type: Boolean, default: true},
-      invitedQuest: {type: Boolean, default: true},
+      unsubscribeFromAll: {$type: Boolean, default: false},
+      newPM: {$type: Boolean, default: true},
+      wonChallenge: {$type: Boolean, default: true},
+      giftedGems: {$type: Boolean, default: true},
+      giftedSubscription: {$type: Boolean, default: true},
+      invitedParty: {$type: Boolean, default: true},
+      invitedGuild: {$type: Boolean, default: true},
+      questStarted: {$type: Boolean, default: true},
+      invitedQuest: {$type: Boolean, default: true},
     },
     suppressModals: {
-      levelUp: {type: Boolean, default: false},
-      hatchPet: {type: Boolean, default: false},
-      raisePet: {type: Boolean, default: false},
-      streak: {type: Boolean, default: false},
+      levelUp: {$type: Boolean, default: false},
+      hatchPet: {$type: Boolean, default: false},
+      raisePet: {$type: Boolean, default: false},
+      streak: {$type: Boolean, default: false},
     },
     tasks: {
-      groupByChallenge: {type: Boolean, default: false}, // @TODO remove? not used
-      confirmScoreNotes: {type: Boolean, default: false}, // @TODO remove? not used
+      groupByChallenge: {$type: Boolean, default: false}, // @TODO remove? not used
+      confirmScoreNotes: {$type: Boolean, default: false}, // @TODO remove? not used
     },
     improvementCategories: {
-      type: Array,
+      $type: Array,
       validate: (categories) => {
         const validCategories = ['work', 'exercise', 'healthWellness', 'school', 'teams', 'chores', 'creativity'];
         let isValidCategory = categories.every(category => validCategories.indexOf(category) !== -1);
@@ -516,42 +516,42 @@ let schema = new Schema({
     blurb: String,
     imageUrl: String,
     name: {
-      type: String,
+      $type: String,
       required: true,
       trim: true,
     },
   },
   stats: {
-    hp: {type: Number, default: shared.maxHealth},
-    mp: {type: Number, default: 10},
-    exp: {type: Number, default: 0},
-    gp: {type: Number, default: 0},
-    lvl: {type: Number, default: 1, min: 1},
+    hp: {$type: Number, default: shared.maxHealth},
+    mp: {$type: Number, default: 10},
+    exp: {$type: Number, default: 0},
+    gp: {$type: Number, default: 0},
+    lvl: {$type: Number, default: 1, min: 1},
 
     // Class System
-    class: {type: String, enum: ['warrior', 'rogue', 'wizard', 'healer'], default: 'warrior', required: true},
-    points: {type: Number, default: 0},
-    str: {type: Number, default: 0},
-    con: {type: Number, default: 0},
-    int: {type: Number, default: 0},
-    per: {type: Number, default: 0},
+    class: {$type: String, enum: ['warrior', 'rogue', 'wizard', 'healer'], default: 'warrior', required: true},
+    points: {$type: Number, default: 0},
+    str: {$type: Number, default: 0},
+    con: {$type: Number, default: 0},
+    int: {$type: Number, default: 0},
+    per: {$type: Number, default: 0},
     buffs: {
-      str: {type: Number, default: 0},
-      int: {type: Number, default: 0},
-      per: {type: Number, default: 0},
-      con: {type: Number, default: 0},
-      stealth: {type: Number, default: 0},
-      streaks: {type: Boolean, default: false},
-      snowball: {type: Boolean, default: false},
-      spookySparkles: {type: Boolean, default: false},
-      shinySeed: {type: Boolean, default: false},
-      seafoam: {type: Boolean, default: false},
+      str: {$type: Number, default: 0},
+      int: {$type: Number, default: 0},
+      per: {$type: Number, default: 0},
+      con: {$type: Number, default: 0},
+      stealth: {$type: Number, default: 0},
+      streaks: {$type: Boolean, default: false},
+      snowball: {$type: Boolean, default: false},
+      spookySparkles: {$type: Boolean, default: false},
+      shinySeed: {$type: Boolean, default: false},
+      seafoam: {$type: Boolean, default: false},
     },
     training: {
-      int: {type: Number, default: 0},
-      per: {type: Number, default: 0},
-      str: {type: Number, default: 0},
-      con: {type: Number, default: 0},
+      int: {$type: Number, default: 0},
+      per: {$type: Number, default: 0},
+      str: {$type: Number, default: 0},
+      con: {$type: Number, default: 0},
     },
   },
 
@@ -560,45 +560,46 @@ let schema = new Schema({
 
   inbox: {
     // messages are stored in the Inbox collection
-    newMessages: {type: Number, default: 0},
-    blocks: {type: Array, default: () => []},
-    optOut: {type: Boolean, default: false},
+    newMessages: {$type: Number, default: 0},
+    blocks: {$type: Array, default: () => []},
+    optOut: {$type: Boolean, default: false},
   },
   tasksOrder: {
-    habits: [{type: String, ref: 'Task'}],
-    dailys: [{type: String, ref: 'Task'}],
-    todos: [{type: String, ref: 'Task'}],
-    rewards: [{type: String, ref: 'Task'}],
+    habits: [{$type: String, ref: 'Task'}],
+    dailys: [{$type: String, ref: 'Task'}],
+    todos: [{$type: String, ref: 'Task'}],
+    rewards: [{$type: String, ref: 'Task'}],
   },
-  extra: {type: Schema.Types.Mixed, default: () => {
+  extra: {$type: Schema.Types.Mixed, default: () => {
     return {};
   }},
   pushDevices: [PushDeviceSchema],
-  _ABtests: {type: Schema.Types.Mixed, default: () => {
+  _ABtests: {$type: Schema.Types.Mixed, default: () => {
     return {};
   }},
   webhooks: [WebhookSchema],
-  loginIncentives: {type: Number, default: 0},
-  invitesSent: {type: Number, default: 0},
+  loginIncentives: {$type: Number, default: 0},
+  invitesSent: {$type: Number, default: 0},
 
   // Items manually pinned by the user
   pinnedItems: [{
     _id: false,
-    path: {type: String},
-    type: {type: String},
+    path: {$type: String},
+    type: {$type: String},
   }],
   // Ordered array of shown pinned items, necessary for sorting because seasonal items are not stored in pinnedItems
-  pinnedItemsOrder: [{type: String}],
+  pinnedItemsOrder: [{$type: String}],
   // Items the user manually unpinned from the ones suggested by Habitica
   unpinnedItems: [{
     _id: false,
-    path: {type: String},
-    type: {type: String},
+    path: {$type: String},
+    type: {$type: String},
   }],
 }, {
   skipVersioning: { notifications: true },
   strict: true,
   minimize: false, // So empty objects are returned
+  typeKey: '$type', // So that we can use fields named `type`
 });
 
 module.exports = schema;
diff --git a/website/server/models/userNotification.js b/website/server/models/userNotification.js
index 6ca205b03c..acb280b16a 100644
--- a/website/server/models/userNotification.js
+++ b/website/server/models/userNotification.js
@@ -37,7 +37,7 @@ const Schema = mongoose.Schema;
 
 export let schema = new Schema({
   id: {
-    type: String,
+    $type: String,
     default: uuid,
     validate: [v => validator.isUUID(v), 'Invalid uuid.'],
     // @TODO: Add these back once we figure out the issue with notifications
@@ -45,25 +45,26 @@ export let schema = new Schema({
     // required: true,
   },
   type: {
-    type: String,
+    $type: String,
     // @TODO: Add these back once we figure out the issue with notifications
     // See Fix for https://github.com/HabitRPG/habitica/issues/9923
     // required: true,
     enum: NOTIFICATION_TYPES,
   },
-  data: {type: Schema.Types.Mixed, default: () => {
+  data: {$type: Schema.Types.Mixed, default: () => {
     return {};
   }},
   // A field to mark the notification as seen without deleting it, optional use
   seen: {
-    type: Boolean,
+    $type: Boolean,
     // required: true,
     default: () => false,
   },
 }, {
   strict: true,
   minimize: false, // So empty objects are returned
-  _id: false, // use id instead of _id
+  _id: false, // use id instead of _id,
+  typeKey: '$type', // So that we can use fields named `type`
 });
 
 /**
diff --git a/website/server/models/webhook.js b/website/server/models/webhook.js
index 3761166619..f4075faf38 100644
--- a/website/server/models/webhook.js
+++ b/website/server/models/webhook.js
@@ -32,13 +32,13 @@ const QUEST_ACTIVITY_DEFAULT_OPTIONS = Object.freeze({
 
 export let schema = new Schema({
   id: {
-    type: String,
+    $type: String,
     required: true,
     validate: [v => validator.isUUID(v), shared.i18n.t('invalidWebhookId')],
     default: uuid,
   },
   type: {
-    type: String,
+    $type: String,
     required: true,
     enum: [
       'globalActivity', // global webhooks send a request for every type of event
@@ -48,12 +48,12 @@ export let schema = new Schema({
     default: 'taskActivity',
   },
   label: {
-    type: String,
+    $type: String,
     required: false,
     default: '',
   },
   url: {
-    type: String,
+    $type: String,
     required: true,
     validate: [(v) => {
       return validator.isURL(v, {
@@ -61,9 +61,9 @@ export let schema = new Schema({
       });
     }, shared.i18n.t('invalidUrl')],
   },
-  enabled: { type: Boolean, required: true, default: true },
+  enabled: { $type: Boolean, required: true, default: true },
   options: {
-    type: Schema.Types.Mixed,
+    $type: Schema.Types.Mixed,
     required: true,
     default () {
       return {};
@@ -73,6 +73,7 @@ export let schema = new Schema({
   strict: true,
   minimize: false, // So empty objects are returned
   _id: false,
+  typeKey: '$type', // So that we can use fields named `type`
 });
 
 schema.plugin(baseModel, {