diff --git a/lib/lamby/rack_alb.rb b/lib/lamby/rack_alb.rb
index 0ca172e..2511ec0 100644
--- a/lib/lamby/rack_alb.rb
+++ b/lib/lamby/rack_alb.rb
@@ -47,9 +47,6 @@ def env_base
         ::Rack::RACK_URL_SCHEME => headers['x-forwarded-proto'],
         ::Rack::RACK_INPUT => StringIO.new(body || ''),
         ::Rack::RACK_ERRORS => $stderr,
-        ::Rack::RACK_MULTITHREAD => false,
-        ::Rack::RACK_MULTIPROCESS => false,
-        ::Rack::RACK_RUNONCE => false,
         LAMBDA_EVENT => event,
         LAMBDA_CONTEXT => context
       }.tap do |env|
diff --git a/lib/lamby/rack_http.rb b/lib/lamby/rack_http.rb
index 48417e9..2c803b3 100644
--- a/lib/lamby/rack_http.rb
+++ b/lib/lamby/rack_http.rb
@@ -42,9 +42,6 @@ def env_base
         ::Rack::RACK_URL_SCHEME => 'https',
         ::Rack::RACK_INPUT => StringIO.new(body || ''),
         ::Rack::RACK_ERRORS => $stderr,
-        ::Rack::RACK_MULTITHREAD => false,
-        ::Rack::RACK_MULTIPROCESS => false,
-        ::Rack::RACK_RUNONCE => false,
         LAMBDA_EVENT => event,
         LAMBDA_CONTEXT => context
       }.tap do |env|
diff --git a/lib/lamby/rack_rest.rb b/lib/lamby/rack_rest.rb
index f16adb6..da13481 100644
--- a/lib/lamby/rack_rest.rb
+++ b/lib/lamby/rack_rest.rb
@@ -36,9 +36,6 @@ def env_base
         ::Rack::RACK_URL_SCHEME => 'https',
         ::Rack::RACK_INPUT => StringIO.new(body || ''),
         ::Rack::RACK_ERRORS => $stderr,
-        ::Rack::RACK_MULTITHREAD => false,
-        ::Rack::RACK_MULTIPROCESS => false,
-        ::Rack::RACK_RUNONCE => false,
         LAMBDA_EVENT => event,
         LAMBDA_CONTEXT => context
       }.tap do |env|