diff --git a/falcon.gemspec b/falcon.gemspec
index 7ce5b8c9..c769837d 100644
--- a/falcon.gemspec
+++ b/falcon.gemspec
@@ -21,7 +21,7 @@ Gem::Specification.new do |spec|
 		
 	spec.add_dependency "async", "~> 1.13"
 	spec.add_dependency "async-io", "~> 1.22"
-	spec.add_dependency "async-http", "~> 0.48.0"
+	spec.add_dependency "async-http"
 	spec.add_dependency "async-container", "~> 0.14.0"
 	
 	spec.add_dependency "rack", ">= 1.0"
diff --git a/lib/falcon/adapters/rack.rb b/lib/falcon/adapters/rack.rb
index f803808a..12ce4356 100644
--- a/lib/falcon/adapters/rack.rb
+++ b/lib/falcon/adapters/rack.rb
@@ -105,6 +105,7 @@ def unwrap_request(request, env)
 				# https://tools.ietf.org/html/rfc7239#section-5.4
 				# https://github.com/rack/rack/issues/1310
 				env[HTTP_X_FORWARDED_PROTO] ||= request.scheme
+				env[RACK_URL_SCHEME] = env[HTTP_X_FORWARDED_PROTO]
 				
 				if remote_address = request.remote_address
 					env[REMOTE_ADDR] = remote_address.ip_address if remote_address.ip?
@@ -157,7 +158,7 @@ def call(request)
 				}
 				
 				self.unwrap_request(request, env)
-				
+
 				if request.push?
 					env[RACK_EARLY_HINTS] = EarlyHints.new(request)
 				end
diff --git a/spec/falcon/adapters/rack_spec.rb b/spec/falcon/adapters/rack_spec.rb
index f2a45e5f..8b467006 100644
--- a/spec/falcon/adapters/rack_spec.rb
+++ b/spec/falcon/adapters/rack_spec.rb
@@ -91,6 +91,28 @@
 		end
 	end
 
+	context "rack.url_scheme" do
+		include_context Falcon::Server
+		let(:protocol) {Async::HTTP::Protocol::HTTP1}
+
+		let(:app) do
+			lambda do |env|
+				[200, {}, ["Scheme: #{env['rack.url_scheme'].inspect}"]]
+			end
+		end
+
+		it 'defaults to http' do
+			response = client.get('/')
+
+			expect(response.read).to be == 'Scheme: "http"'
+		end
+
+		it 'responses X-Forwarded-Proto headers' do
+			response = client.get('/', [["X-Forwarded-Proto", "https"]])
+
+			expect(response.read).to be == 'Scheme: "https"'
+		end
+	end
 	context "early hints" do
 		it_behaves_like Falcon::Adapters::EarlyHints
 	end