diff --git a/CHANGELOG.md b/CHANGELOG.md
index ccb43dc..dbd0558 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,9 @@
 ## [Unreleased]
 
+## [0.1.2] - 2023-03-22
+
+- Fixed Apigatewayv2Rack.handler_from_rack_config_file didn't work well with Rack 3.
+
 ## [0.1.1] - 2022-10-17
 
 - `#to_ary` on response body is no longer called to support Rack::CommonLogger and keep compatibility with Rack 2 specification.
diff --git a/Gemfile.lock b/Gemfile.lock
index 80121b6..e8084be 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -1,14 +1,14 @@
 PATH
   remote: .
   specs:
-    apigatewayv2_rack (0.1.1)
+    apigatewayv2_rack (0.1.2)
       rack
 
 GEM
   remote: https://rubygems.org/
   specs:
     diff-lcs (1.5.0)
-    rack (3.0.0)
+    rack (3.0.7)
     rake (13.0.6)
     rspec (3.11.0)
       rspec-core (~> 3.11.0)
diff --git a/lib/apigatewayv2_rack.rb b/lib/apigatewayv2_rack.rb
index 3b7c628..7bde958 100644
--- a/lib/apigatewayv2_rack.rb
+++ b/lib/apigatewayv2_rack.rb
@@ -31,6 +31,11 @@ def self.generate_handler(app)
   def self.handler_from_rack_config_file(path = './config.ru')
     require 'rack'
     require 'rack/builder'
-    generate_handler(Rack::Builder.load_file(path, {})[0])
+    app = if Rack.release[0] == '2'
+      Rack::Builder.load_file(path, {})[0]
+    else
+      Rack::Builder.load_file(path)
+    end
+    generate_handler(app)
   end
 end
diff --git a/lib/apigatewayv2_rack/version.rb b/lib/apigatewayv2_rack/version.rb
index 17fdaa1..179575f 100644
--- a/lib/apigatewayv2_rack/version.rb
+++ b/lib/apigatewayv2_rack/version.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 
 module Apigatewayv2Rack
-  VERSION = "0.1.1"
+  VERSION = "0.1.2"
 end