diff --git a/grape-msgpack.gemspec b/grape-msgpack.gemspec
index e2acf7f..ae3e1cc 100644
--- a/grape-msgpack.gemspec
+++ b/grape-msgpack.gemspec
@@ -8,8 +8,8 @@ Gem::Specification.new do |spec|
   spec.version       = Grape::Msgpack::VERSION
   spec.authors       = ["Sho Kusano"]
   spec.email         = ["rosylilly@aduca.org"]
-  spec.summary       = %q{msgpack formatter for grape}
-  spec.description   = %q{msgpack formatter for grape}
+  spec.summary       = %q{Messagepack formatter for grape}
+  spec.description   = %q{Messagepack formatter for grape}
   spec.homepage      = ""
   spec.license       = "MIT"
 
@@ -20,10 +20,10 @@ Gem::Specification.new do |spec|
 
   spec.add_development_dependency 'bundler'
   spec.add_development_dependency 'rake'
-  spec.add_development_dependency 'rspec', '~> 2.14.1'
+  spec.add_development_dependency 'rspec', '~> 3.4'
   spec.add_development_dependency 'rack-test', '~> 0.6.2'
-  spec.add_development_dependency 'grape-entity', '~> 0.3.0'
+  spec.add_development_dependency 'grape-entity', '~> 0.5.0'
 
-  spec.add_dependency 'grape', '>= 0.6.0'
-  spec.add_dependency 'msgpack', '~> 0.5.6'
+  spec.add_dependency 'grape'
+  spec.add_dependency 'msgpack', '>= 0.7.4'
 end
diff --git a/lib/grape/msgpack.rb b/lib/grape/msgpack.rb
index c6c2ca7..a17d591 100644
--- a/lib/grape/msgpack.rb
+++ b/lib/grape/msgpack.rb
@@ -36,17 +36,9 @@ def call(object, env)
   end
 end
 
-class << Grape::Formatter::Base
-  FORMATTERS[:msgpack] = Grape::Msgpack::Formatter
-end
-
-class << Grape::ErrorFormatter::Base
-  FORMATTERS[:msgpack] = Grape::Msgpack::ErrorFormatter
-end
-
-class << Grape::Parser::Base
-  PARSERS[:msgpack] = Grape::Msgpack::Parser
-end
+Grape::Formatter.register(:msgpack, Grape::Msgpack::Formatter)
+Grape::ErrorFormatter.register(:msgpack, Grape::Msgpack::ErrorFormatter)
+Grape::Parser.register(:msgpack, Grape::Msgpack::Parser)
 
 Grape::ContentTypes::CONTENT_TYPES[:msgpack] = 'application/x-msgpack'
 
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index ae4e437..96e9ebb 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -2,7 +2,6 @@
 Coveralls.wear!
 
 RSpec.configure do |config|
-  config.treat_symbols_as_metadata_keys_with_true_values = true
   config.run_all_when_everything_filtered = true
   config.filter_run :focus
 end