diff --git a/async-cable.gemspec b/async-cable.gemspec
index da95f60..78a3209 100644
--- a/async-cable.gemspec
+++ b/async-cable.gemspec
@@ -24,7 +24,9 @@ Gem::Specification.new do |spec|
 	
 	spec.required_ruby_version = ">= 3.3"
 	
-	spec.add_dependency "actioncable-next"
+	# Requires the `ActionCable::Server::Socket` abstraction introduced by
+	# https://github.com/rails/rails/pull/50979 (Rails 8.1+).
+	spec.add_dependency "actioncable", ">= 8.1.0.alpha"
 	spec.add_dependency "async", "~> 2.9"
 	spec.add_dependency "async-websocket"
 end
diff --git a/gems.rb b/gems.rb
index 3585cc0..06f869e 100644
--- a/gems.rb
+++ b/gems.rb
@@ -7,8 +7,10 @@
 
 gemspec
 
-# Use the fix branch until https://github.com/anycable/actioncable-next/pull/17 is merged and released.
-gem "actioncable-next", github: "ioquatix/actioncable-next", branch: "fix/close-ensure-socket"
+# The `next` branch targets Rails main, which now includes the
+# `ActionCable::Server::Socket` abstraction (rails/rails#50979) that
+# previously required actioncable-next.
+gem "rails", github: "rails/rails", branch: "main"
 
 gem "async"
 
diff --git a/readme.md b/readme.md
index 49ad304..a5c8884 100644
--- a/readme.md
+++ b/readme.md
@@ -1,6 +1,8 @@
 # Async::Cable
 
-This is a proof-of-concept adapter for Rails 7.2+. It depends on `actioncable-next` which completely replaces the internal implementation of Action Cable with a pluggable one.
+This is a proof-of-concept adapter for Action Cable.
+
+The `next` branch tracks Rails `main` and relies on the `ActionCable::Server::Socket` abstraction introduced by [rails/rails#50979](https://github.com/rails/rails/pull/50979) (Rails 8.1+). For stable Rails (≤ 8.0), use the `main` branch, which depends on [`actioncable-next`](https://github.com/anycable/actioncable-next).
 
 [![Development Status](https://github.com/socketry/async-cable/workflows/Test/badge.svg)](https://github.com/socketry/async-cable/actions?workflow=Test)
 
diff --git a/test/async/cable/middleware.rb b/test/async/cable/middleware.rb
index 87f491e..54d6a9d 100644
--- a/test/async/cable/middleware.rb
+++ b/test/async/cable/middleware.rb
@@ -72,6 +72,81 @@ def url
 		end
 	end
 	
+	with "non-websocket requests" do
+		let(:inner_app) do
+			lambda do |env|
+				[200, {"content-type" => "text/plain"}, ["hello"]]
+			end
+		end
+		
+		let(:app) do
+			Protocol::Rack::Adapter.new(subject.new(inner_app, server: cable_server))
+		end
+		
+		it "forwards non-websocket requests on the cable path to the inner app" do
+			response = client.get("/cable")
+			expect(response.read).to be == "hello"
+		ensure
+			response&.close
+		end
+		
+		it "forwards requests on other paths to the inner app" do
+			response = client.get("/other")
+			expect(response.read).to be == "hello"
+		ensure
+			response&.close
+		end
+	end
+	
+	with "#allow_request_origin?" do
+		let(:middleware) {subject.new(nil, server: cable_server)}
+		
+		before do
+			cable_server.config.disable_request_forgery_protection = false
+		end
+		
+		it "allows requests matching the configured origin host" do
+			cable_server.config.allow_same_origin_as_host = true
+			env = {"HTTP_ORIGIN" => "http://example.com", "HTTP_HOST" => "example.com", "rack.url_scheme" => "http"}
+			expect(middleware.__send__(:allow_request_origin?, env)).to be == true
+		end
+		
+		it "allows requests from explicitly allowed origins" do
+			cable_server.config.allowed_request_origins = ["http://allowed.example"]
+			env = {"HTTP_ORIGIN" => "http://allowed.example", "HTTP_HOST" => "example.com", "rack.url_scheme" => "http"}
+			expect(middleware.__send__(:allow_request_origin?, env)).to be == true
+		end
+		
+		it "rejects requests from disallowed origins" do
+			cable_server.config.allowed_request_origins = ["http://allowed.example"]
+			env = {"HTTP_ORIGIN" => "http://evil.example", "HTTP_HOST" => "example.com", "rack.url_scheme" => "http"}
+			expect(middleware.__send__(:allow_request_origin?, env)).to be == false
+		end
+	end
+	
+	with "#handle_incoming_websocket" do
+		include Sus::Fixtures::Async::ReactorContext
+		
+		let(:middleware) {subject.new(nil, server: cable_server)}
+		
+		# Minimal websocket double whose `read` raises an unexpected error,
+		# exercising the abnormal-failure rescue branch.
+		let(:failing_websocket) do
+			Class.new do
+				def read; raise "unexpected"; end
+				def send_text(_); end
+				def flush; end
+				def closed?; true; end
+				def close_write(_ = nil); end
+			end.new
+		end
+		
+		it "logs unexpected errors and cleans up the connection" do
+			env = {"PATH_INFO" => "/cable", "HTTP_HOST" => "example.com", "rack.url_scheme" => "http"}
+			middleware.__send__(:handle_incoming_websocket, env, failing_websocket)
+		end
+	end
+	
 	it "can connect and receive welcome messages" do
 		welcome_message = connection.read.parse
 		
diff --git a/test/async/cable/socket.rb b/test/async/cable/socket.rb
index 19bf180..b896264 100644
--- a/test/async/cable/socket.rb
+++ b/test/async/cable/socket.rb
@@ -1,10 +1,17 @@
 # frozen_string_literal: true
 
+# Released under the MIT License.
+# Copyright, 2024-2026, by Samuel Williams.
+
 require "async/cable/socket"
 require "action_cable"
+require "action_dispatch"
+require "action_dispatch/http/request"
+require "sus/fixtures/async"
 
 describe Async::Cable::Socket do
-	let(:socket) {subject.new({}, nil, ::ActionCable::Server::Base.new)}
+	let(:server) {::ActionCable::Server::Base.new}
+	let(:socket) {subject.new({}, nil, server)}
 	
 	it "cannot transmit after close" do
 		socket.close
@@ -18,4 +25,57 @@
 		socket.close
 		socket.close
 	end
+	
+	with "#request" do
+		it "builds an ActionDispatch::Request from the Rack environment" do
+			request = socket.request
+			expect(request).to be_a(ActionDispatch::Request)
+		end
+		
+		it "memoizes the request" do
+			expect(socket.request).to be_equal(socket.request)
+		end
+		
+		it "merges Rails.application env_config when available" do
+			fake_application = Object.new
+			def fake_application.env_config; {"rails.test" => true}; end
+			
+			rails_was_defined = defined?(Rails)
+			Object.const_set(:Rails, Module.new) unless rails_was_defined
+			previous = Rails.respond_to?(:application) ? Rails.application : nil
+			Rails.define_singleton_method(:application){fake_application}
+			
+			request = socket.request
+			expect(request.env["rails.test"]).to be == true
+		ensure
+			if rails_was_defined
+				Rails.define_singleton_method(:application){previous}
+			else
+				Object.send(:remove_const, :Rails)
+			end
+		end
+	end
+	
+	with "#run" do
+		include Sus::Fixtures::Async::ReactorContext
+		
+		# Minimal websocket double that raises on send_text, exercising the rescue
+		# branch in Socket#run.
+		let(:failing_websocket) do
+			Class.new do
+				def send_text(_buffer); raise "boom"; end
+				def flush; end
+				def closed?; true; end
+			end.new
+		end
+		
+		let(:socket) {subject.new({}, failing_websocket, server)}
+		
+		it "logs errors raised while draining the output queue" do
+			task = socket.run
+			socket.transmit({type: "ping"})
+			socket.close
+			task.wait
+		end
+	end
 end