diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 98113990..d18e31b6 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        rubyversion: ['2.6', '2.7', '3.0', '3.1', '3.2', '3.3']
+        rubyversion: ['2.6', '2.7', '3.0', '3.1', '3.2', '3.3', '3.4']
     steps:
       - uses: actions/checkout@v4
       - uses: ruby/setup-ruby@v1
@@ -35,7 +35,7 @@ jobs:
       - uses: actions/checkout@v4
       - uses: ruby/setup-ruby@v1
         with:
-          ruby-version: '3.3'
+          ruby-version: '3.4'
           rubygems: '3.3.0'
           bundler-cache: true
       - name: Install Dependencies
@@ -51,7 +51,7 @@ jobs:
       - uses: actions/checkout@v4
       - uses: ruby/setup-ruby@v1
         with:
-          ruby-version: '3.3'
+          ruby-version: '3.4'
           rubygems: '3.3.0'
           bundler-cache: true
       - name: Install Dependencies
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index e96e1a4c..0a27f705 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -12,7 +12,7 @@ jobs:
       - uses: actions/checkout@v4
       - uses: ruby/setup-ruby@v1
         with:
-          ruby-version: '3.3'
+          ruby-version: '3.4'
           rubygems: '3.3.0'
           bundler-cache: true
       - name: Build Package
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 105020f2..7bbf4b5c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,7 +1,9 @@
 # CHANGELOG
 
-## Next Release
+## Next Release (minor)
 
+- Adds Ruby 3.4 support
+- Corrects the HTTP verb for updating a brand from `GET` to `PATCH`
 - Removes the deprecated `create_list` tracker endpoint function as it is no longer available via API
 
 ## v6.4.1 (2024-08-09)
diff --git a/easypost.gemspec b/easypost.gemspec
index 55593c25..8397a057 100644
--- a/easypost.gemspec
+++ b/easypost.gemspec
@@ -21,8 +21,13 @@ Gem::Specification.new do |spec|
   spec.require_paths = ['lib']
   spec.required_ruby_version = '>= 2.6'
 
+  spec.add_development_dependency 'abbrev', '~> 0.1'
+  spec.add_development_dependency 'benchmark', '~> 0.4'
+  spec.add_development_dependency 'bigdecimal', '~> 3'
   spec.add_development_dependency 'brakeman', '~> 5.4'
   spec.add_development_dependency 'faraday', '~> 2.7.5' # used for integration tests
+  spec.add_development_dependency 'logger', '~> 1'
+  spec.add_development_dependency 'ostruct', '~> 0.6'
   spec.add_development_dependency 'pry', '~> 0.14'
   spec.add_development_dependency 'rake', '~> 13.0'
   spec.add_development_dependency 'rdoc', '~> 6.9'
diff --git a/examples b/examples
index 0492e408..7669825f 160000
--- a/examples
+++ b/examples
@@ -1 +1 @@
-Subproject commit 0492e408e1b37b2ec18bcb4a4d228ab0f458f59d
+Subproject commit 7669825fb53be074d7f585c78c4f38ad4fefe0d0
diff --git a/lib/easypost/services/user.rb b/lib/easypost/services/user.rb
index 1703ec94..063643cc 100644
--- a/lib/easypost/services/user.rb
+++ b/lib/easypost/services/user.rb
@@ -74,7 +74,7 @@ def api_keys(id)
   # Update the Brand of a User.
   def update_brand(id, params = {})
     wrapped_params = { brand: params }
-    response = @client.make_request(:get, "users/#{id}/brand", wrapped_params)
+    response = @client.make_request(:patch, "users/#{id}/brand", wrapped_params)
 
     EasyPost::InternalUtilities::Json.convert_json_to_object(response, EasyPost::Models::Brand)
   end
diff --git a/spec/cassettes/user/EasyPost_Services_User_update_brand_updates_the_authenticated_user_s_brand.yml b/spec/cassettes/user/EasyPost_Services_User_update_brand_updates_the_authenticated_user_s_brand.yml
index bac5e30e..15fcc4a4 100644
--- a/spec/cassettes/user/EasyPost_Services_User_update_brand_updates_the_authenticated_user_s_brand.yml
+++ b/spec/cassettes/user/EasyPost_Services_User_update_brand_updates_the_authenticated_user_s_brand.yml
@@ -35,7 +35,7 @@ http_interactions:
       Referrer-Policy:
       - strict-origin-when-cross-origin
       X-Ep-Request-Uuid:
-      - d044fa7b66a7db36e799e564005a6356
+      - 16a5647b67af85a2e787377a0053832a
       Cache-Control:
       - private, no-cache, no-store
       Pragma:
@@ -45,18 +45,18 @@ http_interactions:
       Content-Type:
       - application/json; charset=utf-8
       X-Runtime:
-      - '0.140684'
+      - '0.229489'
       Transfer-Encoding:
       - chunked
       X-Node:
-      - bigweb39nuq
+      - bigweb33nuq
       X-Version-Label:
-      - easypost-202407291746-57ea285141-master
+      - easypost-202502132348-e5a3dc472b-master
       X-Backend:
       - easypost
       X-Proxied:
-      - extlb1nuq fa152d4755
-      - intlb3nuq c0f5e722d1
+      - extlb2nuq 99aac35317
+      - intlb3nuq 51d74985a2
       Strict-Transport-Security:
       - max-age=31536000; includeSubDomains; preload
     body:
@@ -71,14 +71,20 @@ http_interactions:
         User","phone_number":"8005550100","verified":true,"created_at":"2024-07-26T19:08:21Z","default_carbon_offset":false,"has_elevate_access":false,"children":[]},{"id":"user_acfa6f7268d14e449edd1fe6f4ab64cc","object":"User","parent_id":"user_0f6b83e3530b401cb1e8aeaa6a250d4d","name":"Test
         User","phone_number":"8005550100","verified":true,"created_at":"2024-07-29T17:41:32Z","default_carbon_offset":false,"has_elevate_access":false,"children":[]},{"id":"user_4b066506d76940aeb28943506eb76941","object":"User","parent_id":"user_0f6b83e3530b401cb1e8aeaa6a250d4d","name":"Test
         User","phone_number":"8005550100","verified":true,"created_at":"2024-07-29T17:46:31Z","default_carbon_offset":false,"has_elevate_access":false,"children":[]},{"id":"user_48b7c8e5981647a8aee52aa1cb910280","object":"User","parent_id":"user_0f6b83e3530b401cb1e8aeaa6a250d4d","name":"Test
-        User","phone_number":"8005550100","verified":true,"created_at":"2024-07-29T18:07:19Z","default_carbon_offset":false,"has_elevate_access":false,"children":[]}]}'
-  recorded_at: Mon, 29 Jul 2024 18:11:02 GMT
+        User","phone_number":"8005550100","verified":true,"created_at":"2024-07-29T18:07:19Z","default_carbon_offset":false,"has_elevate_access":false,"children":[]},{"id":"user_dc18fb938f184bfd8f345d7fb1469130","object":"User","parent_id":"user_0f6b83e3530b401cb1e8aeaa6a250d4d","name":"Test
+        User","phone_number":"8005550100","verified":true,"created_at":"2024-07-29T21:45:16Z","default_carbon_offset":false,"has_elevate_access":false,"children":[]},{"id":"user_06004d67f8294a73b2a21b62d5a2e3d6","object":"User","parent_id":"user_0f6b83e3530b401cb1e8aeaa6a250d4d","name":"Test
+        User","phone_number":"8005550100","verified":true,"created_at":"2024-07-29T21:50:35Z","default_carbon_offset":false,"has_elevate_access":false,"children":[]},{"id":"user_b760795a35e24bfc803b51b29cca0d7e","object":"User","parent_id":"user_0f6b83e3530b401cb1e8aeaa6a250d4d","name":"Test
+        User","phone_number":"8005550100","verified":true,"created_at":"2024-07-29T21:59:34Z","default_carbon_offset":false,"has_elevate_access":false,"children":[]},{"id":"user_a2e569dd62f14b75b2f8c84aa62ded62","object":"User","parent_id":"user_0f6b83e3530b401cb1e8aeaa6a250d4d","name":"Test
+        User","phone_number":"8005550100","verified":true,"created_at":"2024-07-29T22:03:04Z","default_carbon_offset":false,"has_elevate_access":false,"children":[]},{"id":"user_85480046d6514ea3863eb950fbea392e","object":"User","parent_id":"user_0f6b83e3530b401cb1e8aeaa6a250d4d","name":"Test
+        User","phone_number":"8005550100","verified":true,"created_at":"2024-07-29T22:04:22Z","default_carbon_offset":false,"has_elevate_access":false,"children":[]},{"id":"user_89583592d7914082b3b61fdf9230db38","object":"User","parent_id":"user_0f6b83e3530b401cb1e8aeaa6a250d4d","name":"Test
+        User","phone_number":"8005550100","verified":true,"created_at":"2024-08-01T17:06:15Z","default_carbon_offset":false,"has_elevate_access":false,"children":[]}]}'
+  recorded_at: Fri, 14 Feb 2025 18:04:18 GMT
 - request:
-    method: get
-    uri: https://api.easypost.com/v2/users/user_0f6b83e3530b401cb1e8aeaa6a250d4d/brand?brand=%7B:color=%3E%22%23123456%22%7D
+    method: patch
+    uri: https://api.easypost.com/v2/users/user_0f6b83e3530b401cb1e8aeaa6a250d4d/brand
     body:
-      encoding: US-ASCII
-      string: ''
+      encoding: UTF-8
+      string: '{"brand":{"color":"#123456"}}'
     headers:
       Accept-Encoding:
       - gzip;q=1.0,deflate;q=0.6,identity;q=0.3
@@ -108,7 +114,7 @@ http_interactions:
       Referrer-Policy:
       - strict-origin-when-cross-origin
       X-Ep-Request-Uuid:
-      - d044fa7466a7db37e799e566005a63f6
+      - 16a5647e67af85a2e787377d005383ac
       Cache-Control:
       - private, no-cache, no-store
       Pragma:
@@ -118,22 +124,22 @@ http_interactions:
       Content-Type:
       - application/json; charset=utf-8
       X-Runtime:
-      - '0.090249'
+      - '0.101178'
       Transfer-Encoding:
       - chunked
       X-Node:
-      - bigweb33nuq
+      - bigweb54nuq
       X-Version-Label:
-      - easypost-202407291746-57ea285141-master
+      - easypost-202502132348-e5a3dc472b-master
       X-Backend:
       - easypost
       X-Proxied:
-      - extlb1nuq fa152d4755
-      - intlb4nuq c0f5e722d1
+      - extlb2nuq 99aac35317
+      - intlb4nuq 51d74985a2
       Strict-Transport-Security:
       - max-age=31536000; includeSubDomains; preload
     body:
       encoding: UTF-8
       string: '{"ad":null,"ad_href":null,"background_color":null,"color":"#123456","id":"brd_136abcc3c9de49fcb1a0e963f26fdcac","logo":"https://assets.easypost.com/assets/images/branding/easypost-primary-logo.7324aa54b64b34d6cd70ca5ba4d1842d.svg","logo_href":"https://www.easypost.com","name":"EasyPost","object":"Brand","theme":"theme1","user_id":"user_0f6b83e3530b401cb1e8aeaa6a250d4d"}'
-  recorded_at: Mon, 29 Jul 2024 18:11:03 GMT
-recorded_with: VCR 6.1.0
+  recorded_at: Fri, 14 Feb 2025 18:04:18 GMT
+recorded_with: VCR 6.2.0
diff --git a/spec/cassettes/webhook/EasyPost_Services_Webhook_create_creates_a_webhook.yml b/spec/cassettes/webhook/EasyPost_Services_Webhook_create_creates_a_webhook.yml
index 93eb70ac..75e0e41b 100644
--- a/spec/cassettes/webhook/EasyPost_Services_Webhook_create_creates_a_webhook.yml
+++ b/spec/cassettes/webhook/EasyPost_Services_Webhook_create_creates_a_webhook.yml
@@ -5,7 +5,7 @@ http_interactions:
     uri: https://api.easypost.com/v2/webhooks
     body:
       encoding: UTF-8
-      string: '{"webhook":{"url":"http://example.com"}}'
+      string: '{"webhook":{"url":"http://example.com","webhook_secret":"sécret","custom_headers":[{"name":"test","value":"header"}]}}'
     headers:
       Accept-Encoding:
       - gzip;q=1.0,deflate;q=0.6,identity;q=0.3
@@ -35,7 +35,7 @@ http_interactions:
       Referrer-Policy:
       - strict-origin-when-cross-origin
       X-Ep-Request-Uuid:
-      - d044fa7866a7db38e799e581005a65cd
+      - 4b64bb4d67b62818e2b8ff700009ab69
       Cache-Control:
       - private, no-cache, no-store
       Pragma:
@@ -45,27 +45,27 @@ http_interactions:
       Content-Type:
       - application/json; charset=utf-8
       X-Runtime:
-      - '0.195541'
+      - '0.426072'
       Transfer-Encoding:
       - chunked
       X-Node:
-      - bigweb38nuq
+      - bigweb36nuq
       X-Version-Label:
-      - easypost-202407291746-57ea285141-master
+      - easypost-202502191732-9cdc8ea15b-master
       X-Backend:
       - easypost
       X-Proxied:
-      - extlb1nuq fa152d4755
-      - intlb4nuq c0f5e722d1
+      - extlb1nuq 99aac35317
+      - intlb3nuq 51d74985a2
       Strict-Transport-Security:
       - max-age=31536000; includeSubDomains; preload
     body:
       encoding: UTF-8
-      string: '{"id":"hook_eba4eaf24dd511efa52d5d09a9f2573c","object":"Webhook","mode":"test","url":"http://example.com","created_at":"2024-07-29T18:11:05Z","disabled_at":null}'
-  recorded_at: Mon, 29 Jul 2024 18:11:04 GMT
+      string: '{"id":"hook_78e7a450eef211ef927d05e2cbdc7978","object":"Webhook","mode":"test","url":"http://example.com","created_at":"2025-02-19T18:51:05Z","disabled_at":null,"custom_headers":[{"name":"test","value":"header"}]}'
+  recorded_at: Wed, 19 Feb 2025 18:51:05 GMT
 - request:
     method: delete
-    uri: https://api.easypost.com/v2/webhooks/hook_eba4eaf24dd511efa52d5d09a9f2573c
+    uri: https://api.easypost.com/v2/webhooks/hook_78e7a450eef211ef927d05e2cbdc7978
     body:
       encoding: US-ASCII
       string: ''
@@ -98,7 +98,7 @@ http_interactions:
       Referrer-Policy:
       - strict-origin-when-cross-origin
       X-Ep-Request-Uuid:
-      - d044fa7966a7db39e799e582005a6689
+      - 3c3ed33267b62819e2b8ff720008eb31
       Cache-Control:
       - private, no-cache, no-store
       Pragma:
@@ -108,22 +108,22 @@ http_interactions:
       Content-Type:
       - application/json; charset=utf-8
       X-Runtime:
-      - '0.370557'
+      - '0.241701'
       Transfer-Encoding:
       - chunked
       X-Node:
-      - bigweb35nuq
+      - bigweb33nuq
       X-Version-Label:
-      - easypost-202407291746-57ea285141-master
+      - easypost-202502191732-9cdc8ea15b-master
       X-Backend:
       - easypost
       X-Proxied:
-      - extlb1nuq fa152d4755
-      - intlb4nuq c0f5e722d1
+      - extlb2nuq 99aac35317
+      - intlb3nuq 51d74985a2
       Strict-Transport-Security:
       - max-age=31536000; includeSubDomains; preload
     body:
       encoding: UTF-8
       string: "{}"
-  recorded_at: Mon, 29 Jul 2024 18:11:05 GMT
-recorded_with: VCR 6.1.0
+  recorded_at: Wed, 19 Feb 2025 18:51:05 GMT
+recorded_with: VCR 6.2.0
diff --git a/spec/cassettes/webhook/EasyPost_Services_Webhook_update_updates_a_webhook.yml b/spec/cassettes/webhook/EasyPost_Services_Webhook_update_updates_a_webhook.yml
index 1cb8ce6a..7c1b2df7 100644
--- a/spec/cassettes/webhook/EasyPost_Services_Webhook_update_updates_a_webhook.yml
+++ b/spec/cassettes/webhook/EasyPost_Services_Webhook_update_updates_a_webhook.yml
@@ -35,7 +35,7 @@ http_interactions:
       Referrer-Policy:
       - strict-origin-when-cross-origin
       X-Ep-Request-Uuid:
-      - d044fa7666a7db3ce799e587005a69a5
+      - 4b64bb5067b6283ae2b8ffd60009d020
       Cache-Control:
       - private, no-cache, no-store
       Pragma:
@@ -45,30 +45,30 @@ http_interactions:
       Content-Type:
       - application/json; charset=utf-8
       X-Runtime:
-      - '0.180870'
+      - '0.109819'
       Transfer-Encoding:
       - chunked
       X-Node:
-      - bigweb36nuq
+      - bigweb35nuq
       X-Version-Label:
-      - easypost-202407291746-57ea285141-master
+      - easypost-202502191732-9cdc8ea15b-master
       X-Backend:
       - easypost
       X-Proxied:
-      - extlb1nuq fa152d4755
-      - intlb3nuq c0f5e722d1
+      - extlb1nuq 99aac35317
+      - intlb3nuq 51d74985a2
       Strict-Transport-Security:
       - max-age=31536000; includeSubDomains; preload
     body:
       encoding: UTF-8
-      string: '{"id":"hook_edd8938c4dd511ef8af45962431e1651","object":"Webhook","mode":"test","url":"http://example.com","created_at":"2024-07-29T18:11:09Z","disabled_at":null}'
-  recorded_at: Mon, 29 Jul 2024 18:11:08 GMT
+      string: '{"id":"hook_8cbab03aeef211efabe53931f5ecc7b8","object":"Webhook","mode":"test","url":"http://example.com","created_at":"2025-02-19T18:51:38Z","disabled_at":null,"custom_headers":[]}'
+  recorded_at: Wed, 19 Feb 2025 18:51:38 GMT
 - request:
     method: patch
-    uri: https://api.easypost.com/v2/webhooks/hook_edd8938c4dd511ef8af45962431e1651
+    uri: https://api.easypost.com/v2/webhooks/hook_8cbab03aeef211efabe53931f5ecc7b8
     body:
       encoding: UTF-8
-      string: "{}"
+      string: '{"webhook_secret":"sécret","custom_headers":[{"name":"test","value":"header"}]}'
     headers:
       Accept-Encoding:
       - gzip;q=1.0,deflate;q=0.6,identity;q=0.3
@@ -98,7 +98,7 @@ http_interactions:
       Referrer-Policy:
       - strict-origin-when-cross-origin
       X-Ep-Request-Uuid:
-      - d044fa7666a7db3de799e59f005a6a43
+      - 4b64bb5067b6283ae2b8ffd90009d056
       Cache-Control:
       - private, no-cache, no-store
       Pragma:
@@ -108,27 +108,27 @@ http_interactions:
       Content-Type:
       - application/json; charset=utf-8
       X-Runtime:
-      - '0.489107'
+      - '0.609185'
       Transfer-Encoding:
       - chunked
       X-Node:
-      - bigweb53nuq
+      - bigweb58nuq
       X-Version-Label:
-      - easypost-202407291746-57ea285141-master
+      - easypost-202502191732-9cdc8ea15b-master
       X-Backend:
       - easypost
       X-Proxied:
-      - extlb1nuq fa152d4755
-      - intlb3nuq c0f5e722d1
+      - extlb1nuq 99aac35317
+      - intlb4nuq 51d74985a2
       Strict-Transport-Security:
       - max-age=31536000; includeSubDomains; preload
     body:
       encoding: UTF-8
-      string: '{"id":"hook_edd8938c4dd511ef8af45962431e1651","object":"Webhook","mode":"test","url":"http://example.com","created_at":"2024-07-29T18:11:09Z","disabled_at":null}'
-  recorded_at: Mon, 29 Jul 2024 18:11:09 GMT
+      string: '{"id":"hook_8cbab03aeef211efabe53931f5ecc7b8","object":"Webhook","mode":"test","url":"http://example.com","created_at":"2025-02-19T18:51:38Z","disabled_at":null,"custom_headers":[{"name":"test","value":"header"}]}'
+  recorded_at: Wed, 19 Feb 2025 18:51:38 GMT
 - request:
     method: delete
-    uri: https://api.easypost.com/v2/webhooks/hook_edd8938c4dd511ef8af45962431e1651
+    uri: https://api.easypost.com/v2/webhooks/hook_8cbab03aeef211efabe53931f5ecc7b8
     body:
       encoding: US-ASCII
       string: ''
@@ -161,7 +161,7 @@ http_interactions:
       Referrer-Policy:
       - strict-origin-when-cross-origin
       X-Ep-Request-Uuid:
-      - d044fa7966a7db3de799e5a1005a6b23
+      - 4b64bb4e67b6283be2b8ffdc0009d11a
       Cache-Control:
       - private, no-cache, no-store
       Pragma:
@@ -171,22 +171,22 @@ http_interactions:
       Content-Type:
       - application/json; charset=utf-8
       X-Runtime:
-      - '0.338752'
+      - '0.304757'
       Transfer-Encoding:
       - chunked
       X-Node:
-      - bigweb38nuq
+      - bigweb33nuq
       X-Version-Label:
-      - easypost-202407291746-57ea285141-master
+      - easypost-202502191732-9cdc8ea15b-master
       X-Backend:
       - easypost
       X-Proxied:
-      - extlb1nuq fa152d4755
-      - intlb4nuq c0f5e722d1
+      - extlb1nuq 99aac35317
+      - intlb3nuq 51d74985a2
       Strict-Transport-Security:
       - max-age=31536000; includeSubDomains; preload
     body:
       encoding: UTF-8
       string: "{}"
-  recorded_at: Mon, 29 Jul 2024 18:11:10 GMT
-recorded_with: VCR 6.1.0
+  recorded_at: Wed, 19 Feb 2025 18:51:39 GMT
+recorded_with: VCR 6.2.0
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index 9101fdb8..04f27e0c 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -61,7 +61,7 @@ def create_and_insure_shipment(client, amount)
 def check_expired_cassette(cassette_path)
   full_cassette_path = "#{"spec/cassettes/#{cassette_path}".gsub('::', '_').gsub(' ', '_').gsub('.', '_')}.yml"
   seconds_in_day = 86_400
-  expiration_days = 180
+  expiration_days = 365
   expiration_seconds = seconds_in_day * expiration_days
 
   return unless File.exist?(full_cassette_path)
diff --git a/spec/support/fixture.rb b/spec/support/fixture.rb
index e081ce06..7edbe4ff 100644
--- a/spec/support/fixture.rb
+++ b/spec/support/fixture.rb
@@ -129,15 +129,19 @@ def self.event_bytes
   end
 
   def self.webhook_hmac_signature
-    read_fixture_data['webhook_hmac_signature']
+    read_fixture_data['webhooks']['hmac_signature']
   end
 
   def self.webhook_secret
-    read_fixture_data['webhook_secret']
+    read_fixture_data['webhooks']['secret']
   end
 
   def self.webhook_url
-    read_fixture_data['webhook_url']
+    read_fixture_data['webhooks']['url']
+  end
+
+  def self.webhook_custom_headers
+    read_fixture_data['webhooks']['custom_headers']
   end
 
   # The credit card details below are for a valid proxy card usable
diff --git a/spec/user_spec.rb b/spec/user_spec.rb
index 999f4bb3..193073b5 100644
--- a/spec/user_spec.rb
+++ b/spec/user_spec.rb
@@ -71,7 +71,7 @@
 
       brand = client.user.update_brand(
         user.id,
-        color: color,
+        { color: color },
       )
 
       expect(brand).to be_an_instance_of(EasyPost::Models::Brand)
diff --git a/spec/webhook_spec.rb b/spec/webhook_spec.rb
index b77c2c81..3cfef98e 100644
--- a/spec/webhook_spec.rb
+++ b/spec/webhook_spec.rb
@@ -9,11 +9,15 @@
     it 'creates a webhook' do
       webhook = client.webhook.create(
         url: Fixture.webhook_url,
+        webhook_secret: Fixture.webhook_secret,
+        custom_headers: Fixture.webhook_custom_headers,
       )
 
       expect(webhook).to be_an_instance_of(EasyPost::Models::Webhook)
       expect(webhook.id).to match('hook_')
       expect(webhook.url).to eq(Fixture.webhook_url)
+      expect(webhook.custom_headers[0].name).to eq('test')
+      expect(webhook.custom_headers[0].value).to eq('header')
 
       # Remove the webhook once we have tested it so we don't pollute the account with test webhooks
       client.webhook.delete(webhook.id)
@@ -55,9 +59,16 @@
         url: Fixture.webhook_url,
       )
 
-      updated_webhook = client.webhook.update(webhook.id)
+      updated_webhook = client.webhook.update(
+        webhook.id, {
+          webhook_secret: Fixture.webhook_secret,
+          custom_headers: Fixture.webhook_custom_headers,
+        },
+      )
 
       expect(updated_webhook).to be_an_instance_of(EasyPost::Models::Webhook)
+      expect(updated_webhook.custom_headers[0].name).to eq('test')
+      expect(updated_webhook.custom_headers[0].value).to eq('header')
 
       client.webhook.delete(webhook.id) # Remove the webhook once we have tested it so we don't pollute the account with test webhooks
     end