diff --git a/ffi/Gemfile b/ffi/Gemfile
index f80e899..0bbe487 100644
--- a/ffi/Gemfile
+++ b/ffi/Gemfile
@@ -12,5 +12,9 @@ end
 group :test do
   gem "async"
   gem "io-endpoint"
+  # io-event 1.9.0 broke the compat with our "fork based test"
+  # See discussion in https://github.com/bryanp/llhttp/pull/34
+  #               and https://github.com/socketry/io-event/issues/36
+  gem "io-event", "~> 1.8.0"
   gem "rspec"
 end
diff --git a/ffi/lib/llhttp.rb b/ffi/lib/llhttp.rb
index 236c81e..329b06c 100644
--- a/ffi/lib/llhttp.rb
+++ b/ffi/lib/llhttp.rb
@@ -10,6 +10,7 @@ module LLHttp
   require_relative "llhttp/version"
 
   extend FFI::Library
+
   ffi_lib(FFI::Compiler::Loader.find("llhttp-ext"))
 
   callback :llhttp_data_cb, [:pointer, :size_t], :void
diff --git a/mri/Gemfile b/mri/Gemfile
index f80e899..0bbe487 100644
--- a/mri/Gemfile
+++ b/mri/Gemfile
@@ -12,5 +12,9 @@ end
 group :test do
   gem "async"
   gem "io-endpoint"
+  # io-event 1.9.0 broke the compat with our "fork based test"
+  # See discussion in https://github.com/bryanp/llhttp/pull/34
+  #               and https://github.com/socketry/io-event/issues/36
+  gem "io-event", "~> 1.8.0"
   gem "rspec"
 end
diff --git a/mri/lib/llhttp/parser.rb b/mri/lib/llhttp/parser.rb
index 949e4e2..95f82aa 100644
--- a/mri/lib/llhttp/parser.rb
+++ b/mri/lib/llhttp/parser.rb
@@ -49,4 +49,4 @@ def initialize(delegate, type: :both)
   end
 end
 
-require_relative "../llhttp_ext"
+require "llhttp_ext"