Use native llhttp gem on MRI (#800)

All other rubies continue to use `llhttp-ffi`

Author: sebyx07

CHANGELOG.md

@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Changed
+
+- Use native llhttp gem for MRI Ruby and llhttp-ffi for other interpreters for better performance
+
 ### Removed
 
 - **BREAKING** Drop Ruby 2.x support

http.gemspec

@@ -30,7 +30,13 @@ Gem::Specification.new do |gem|
   gem.add_runtime_dependency "addressable",    "~> 2.8"
   gem.add_runtime_dependency "http-cookie",    "~> 1.0"
   gem.add_runtime_dependency "http-form_data", "~> 2.2"
-  gem.add_runtime_dependency "llhttp-ffi",     "~> 0.5.0"
+
+  # Use native llhttp for MRI (more performant) and llhttp-ffi for other interpreters (better compatibility)
+  if RUBY_ENGINE == "ruby"
+    gem.add_runtime_dependency "llhttp",     "~> 0.5.0"
+  else
+    gem.add_runtime_dependency "llhttp-ffi", "~> 0.5.0"
+  end
 
   gem.metadata = {
     "source_code_uri"       => "https://github.com/httprb/http",