diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1014e94..f6b9785 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,6 +9,26 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 
+- **New Feature**: `contacts.deleteByEmail()` method for deleting contacts by email address
+  - Added `deleteByEmail(email: string)` method to Contacts API
+  - Properly handles URL encoding of email addresses with special characters
+  - Returns same response format as existing `delete()` method: `{ isDeleted: boolean, contact: Contact }`
+  - Added comprehensive tests and example usage
+  - Integrates with new SMASHSEND backend endpoint `/v1/contacts/by-email/{email}`
+
+## [1.16.0] - 2025-01-21
+
+### Changed
+
+- **BREAKING**: Simplified transactional email response format to match backend API changes
+  - `RawEmailSendResponse` now returns: `{ messageId, status, to, warning?, groupBy? }`
+  - `TemplatedEmailSendResponse` now returns: `{ messageId, status, to, warning? }`
+  - Removed deprecated fields: `from`, `subject`, `type`, `template`, `created`, `statusCode`, `message`
+  - Updated all tests to use the new response format
+  - This change aligns the Node.js SDK with the simplified backend response schema
+
+### Added
+
 - **Dynamic Reply-To Addresses**: Added support for custom reply-to addresses in both raw and templated emails
   - 📧 **Multiple addresses**: Support for up to 5 reply-to addresses per email
   - 🔄 **Flexible input**: Accept single email string or array of email strings
diff --git a/package.json b/package.json
index afaaa96..e54e314 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@smashsend/node",
-  "version": "1.15.0",
+  "version": "1.16.0",
   "description": "SMASHSEND Node.js SDK - Official Node.js client for SMASHSEND API",
   "main": "dist/index.js",
   "module": "dist/index.mjs",
diff --git a/src/interfaces/events.ts b/src/interfaces/events.ts
index 6f84873..5904dd7 100644
--- a/src/interfaces/events.ts
+++ b/src/interfaces/events.ts
@@ -1,20 +1,49 @@
 // Events API types for SMASHSEND
 
+/**
+ * User traits/attributes to sync with contact record
+ */
+export interface EventTraits {
+  [key: string]: any;
+}
+
+/**
+ * User identification information
+ */
+export interface EventIdentify {
+  /** User email address (required) */
+  email: string;
+  /**
+   * User traits/attributes to sync with contact record
+   * This is optional, and will be ignored if not provided.
+   **/
+  traits?: EventTraits;
+}
+
 /**
  * Event tracking payload for single event
  */
 export interface EventPayload {
-  /** Event name (alphanumeric, underscores, hyphens, dots, colons only) */
+  /**
+   * Event name (alphanumeric, underscores, hyphens, dots, colons only)
+   **/
   event: string;
-  /** Event properties - key-value pairs with any data */
+
+  /**
+   * Event properties - key-value pairs with any data
+   **/
   properties?: Record<string, any>;
-  /** User identification information */
-  identify: {
-    /** User email address (required) */
-    email: string;
-  };
-  /** Event timestamp (ISO string or Unix timestamp) */
+
+  /**
+   * User identification information
+   **/
+  identify: EventIdentify;
+
+  /**
+   * Event timestamp (ISO string or Unix timestamp)
+   **/
   timestamp?: string | number;
+
   /**
    * Optional message ID for deduplication.
    * If not provided, SMASHSEND will generate one automatically.
diff --git a/src/interfaces/types.ts b/src/interfaces/types.ts
index 33f62e5..2b35722 100644
--- a/src/interfaces/types.ts
+++ b/src/interfaces/types.ts
@@ -126,12 +126,6 @@ export interface RawEmailSendResponse {
   status: TransactionalEmailStatus;
   /** Recipient address. */
   to: string;
-  /** Sender address. */
-  from: string;
-  /** Subject line. */
-  subject: string;
-  /** Discriminator – always `raw`. */
-  type: 'raw';
   /** Warning returned by backend when the email is accepted with caveats. */
   warning?: string;
   /** Custom analytics group identifier if provided. */
@@ -145,10 +139,6 @@ export interface TemplatedEmailSendResponse {
   status: TransactionalEmailStatus;
   /** Recipient address. */
   to: string;
-  /** Template identifier sent in the request. */
-  template: string;
-  /** Discriminator – always `templated`. */
-  type: 'templated';
   /** Warning returned by backend when the email is accepted with caveats. */
   warning?: string;
 }