diff --git a/ts/components/conversation/media-gallery/groupMessagesByDate.ts b/ts/components/conversation/media-gallery/groupMessagesByDate.ts
index fac79dcb3d..8f280d22f3 100644
--- a/ts/components/conversation/media-gallery/groupMessagesByDate.ts
+++ b/ts/components/conversation/media-gallery/groupMessagesByDate.ts
@@ -76,7 +76,7 @@ const toSection = (
     case 'thisMonth':
       return {
         type: firstMessageWithSection.type,
-        messages: messages,
+        messages,
       };
     case 'yearMonth':
       return {
@@ -94,11 +94,11 @@ const toSection = (
   }
 };
 
-type GenericMessageWithSection<T> = {
+interface GenericMessageWithSection<T> {
   order: number;
   type: T;
   message: Message;
-};
+}
 type MessageWithStaticSection = GenericMessageWithSection<StaticSectionType>;
 type MessageWithYearMonthSection = GenericMessageWithSection<
   YearMonthSectionType
diff --git a/ts/test/html/index_test.ts b/ts/test/html/index_test.ts
index f2c4602a5c..87ffc84a94 100644
--- a/ts/test/html/index_test.ts
+++ b/ts/test/html/index_test.ts
@@ -57,7 +57,7 @@ describe('HTML', () => {
       },
     ];
 
-    TESTS.forEach((test) => {
+    TESTS.forEach(test => {
       (test.skipped ? it.skip : it)(`should handle ${test.name}`, () => {
         const preText = test.preText || 'Hello ';
         const postText = test.postText || ' World!';
diff --git a/ts/types/Message.ts b/ts/types/Message.ts
index bb01ef089b..0be2060251 100644
--- a/ts/types/Message.ts
+++ b/ts/types/Message.ts
@@ -66,16 +66,20 @@ type SharedMessageProperties = Readonly<{
   timestamp: number;
 }>;
 
-type ExpirationTimerUpdate = Readonly<{
-  expirationTimerUpdate?: Readonly<{
-    expireTimer: number;
-    fromSync: boolean;
-    source: string; // PhoneNumber
-  }>;
-}>;
+type ExpirationTimerUpdate = Partial<
+  Readonly<{
+    expirationTimerUpdate: Readonly<{
+      expireTimer: number;
+      fromSync: boolean;
+      source: string; // PhoneNumber
+    }>;
+  }>
+>;
 
-type Message4 = Partial<Readonly<{
-  hasAttachments: IndexableBoolean;
-  hasVisualMediaAttachments: IndexableBoolean;
-  hasFileAttachments: IndexableBoolean;
-}>>;
+type Message4 = Partial<
+  Readonly<{
+    hasAttachments: IndexableBoolean;
+    hasVisualMediaAttachments: IndexableBoolean;
+    hasFileAttachments: IndexableBoolean;
+  }>
+>;
diff --git a/ts/types/backbone/Collection.ts b/ts/types/backbone/Collection.ts
index e3ffe8139a..c67b2051f6 100644
--- a/ts/types/backbone/Collection.ts
+++ b/ts/types/backbone/Collection.ts
@@ -6,6 +6,6 @@ import { Model } from './Model';
 export interface Collection<T> {
   models: Array<Model<T>>;
   // tslint:disable-next-line no-misused-new
-  new(): Collection<T>;
+  new (): Collection<T>;
   fetch(options: object): JQuery.Deferred<any, any, any>;
 }
diff --git a/ts/types/message/initializeAttachmentMetadata.ts b/ts/types/message/initializeAttachmentMetadata.ts
index 697390f3b3..251529695c 100644
--- a/ts/types/message/initializeAttachmentMetadata.ts
+++ b/ts/types/message/initializeAttachmentMetadata.ts
@@ -8,18 +8,20 @@ import * as IndexedDB from '../IndexedDB';
 import { Message } from '../Message';
 
 export const initializeAttachmentMetadata = async (
-  message: Message,
+  message: Message
 ): Promise<Message> => {
   if (message.type === 'verified-change') {
     return message;
   }
 
-  const hasAttachments = IndexedDB.toIndexableBoolean(message.attachments.length > 0);
+  const hasAttachments = IndexedDB.toIndexableBoolean(
+    message.attachments.length > 0
+  );
   const [hasVisualMediaAttachments, hasFileAttachments] = partition(
     message.attachments,
-    Attachment.isVisualMedia,
+    Attachment.isVisualMedia
   )
-    .map((attachments) => attachments.length > 0)
+    .map(attachments => attachments.length > 0)
     .map(IndexedDB.toIndexableBoolean);
 
   return {