diff --git a/CHANGELOG.md b/CHANGELOG.md
index e49bece..cf64012 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,6 +11,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - Replace mimemagic with marcel.
 
+### Fixed
+
+- Fix error on activesupport 7.
+
 ## 0.9.2 - 2020-12-03
 
 ### Fixed
diff --git a/lib/weneedfeed/faraday_response_middleware.rb b/lib/weneedfeed/faraday_response_middleware.rb
index a3c7637..a14fe33 100644
--- a/lib/weneedfeed/faraday_response_middleware.rb
+++ b/lib/weneedfeed/faraday_response_middleware.rb
@@ -1,5 +1,12 @@
 # frozen_string_literal: true
 
+# For faraday_middleware/response_middleware.
+# https://github.com/r7kamura/weneedfeed/issues/19
+require 'active_support'
+if ActiveSupport.gem_version > Gem::Version.new('7')
+  require 'active_support/isolated_execution_state'
+end
+
 require 'active_support/core_ext/array/conversions'
 require 'active_support/core_ext/hash/conversions'
 require 'faraday'