diff --git a/Gemfile b/Gemfile
index 9db1cc92..d7057efa 100644
--- a/Gemfile
+++ b/Gemfile
@@ -73,7 +73,7 @@ gem 'http'
 gem 'cancancan'
 gem 'dalli'
 gem 'retries'
-gem 'zipline', '~> 2.0'
+gem 'zip_kit', '~> 6.3'
 gem 'jwt'
 gem 'redis'
 
diff --git a/Gemfile.lock b/Gemfile.lock
index f839fe0a..29aa3185 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -124,7 +124,6 @@ GEM
       deep_merge (~> 1.2, >= 1.2.1)
       ostruct
     connection_pool (2.4.1)
-    content_disposition (1.0.0)
     crack (1.0.0)
       bigdecimal
       rexml
@@ -397,10 +396,6 @@ GEM
       nokogiri (~> 1.8)
     zeitwerk (2.7.1)
     zip_kit (6.3.1)
-    zipline (2.0.0)
-      actionpack (>= 6.0, < 8.0)
-      content_disposition (~> 1.0)
-      zip_kit (~> 6, >= 6.2.0, < 7)
 
 PLATFORMS
   arm64-darwin-23
@@ -449,7 +444,7 @@ DEPENDENCIES
   web-console (>= 4.1.0)
   webdrivers
   webmock (~> 3.0)
-  zipline (~> 2.0)
+  zip_kit (~> 6.3)
 
 BUNDLED WITH
    2.5.14
diff --git a/app/controllers/object_controller.rb b/app/controllers/object_controller.rb
index 515dd91e..2c20d48d 100644
--- a/app/controllers/object_controller.rb
+++ b/app/controllers/object_controller.rb
@@ -3,8 +3,6 @@
 ##
 # API for delivering whole objects from stacks
 class ObjectController < ApplicationController
-  include Zipline
-
   # Return a zip of all the files if they have access to all the files.
   # This will force a login if any of the files is not access=world
   def show
@@ -15,25 +13,28 @@ def show
     files.each do |file|
       authorize! :download, file
     end
-    zip_contents = files.map do |file|
-      [
-        file,
-        file.file_name,
-        modification_time: file.mtime
-      ]
+
+    track_download
+
+    zip_kit_stream(filename: "#{druid}.zip") do |zip|
+      files.each do |stacks_file|
+        zip.write_file(stacks_file.file_name, modification_time: stacks_file.mtime) do |sink|
+          File.open(stacks_file.path, "rb") { |file_input| IO.copy_stream(file_input, sink) }
+        end
+      end
     end
+  end
 
+  private
+
+  def track_download
     TrackDownloadJob.perform_later(
       druid:,
       user_agent: request.user_agent,
       ip: request.remote_ip
     )
-
-    zipline(zip_contents, "#{druid}.zip")
   end
 
-  private
-
   def druid
     params[:id]
   end
diff --git a/app/models/cocina.rb b/app/models/cocina.rb
index e56c49bb..54597fd7 100644
--- a/app/models/cocina.rb
+++ b/app/models/cocina.rb
@@ -6,6 +6,7 @@ class Cocina
 
   THUMBNAIL_MIME_TYPE = 'image/jp2'
 
+  # @return [Cocina] Returns the cocina object for the given druid and version
   def self.find(druid, version = :head)
     data = Rails.cache.fetch(metadata_cache_key(druid, version), expires_in: 10.minutes) do
       benchmark "Fetching public json for #{druid} version #{version}" do
@@ -73,6 +74,7 @@ def embargo_release_date
     data.dig('access', 'embargo', 'releaseDate')
   end
 
+  # @return [Enumerator<StacksFile>] when no block is passed
   def files(&)
     return to_enum(:files) unless block_given?