diff --git a/.gitignore b/.gitignore
index 2260ce0..d6be509 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,5 @@
-# See https://help.github.com/articles/ignoring-files for more about ignoring files.
+# See https://help.github.com/articles/ignoring-files
+# for more about ignoring files.
 #
 # If you find yourself ignoring temporary files generated by your text editor
 # or operating system, you probably want to add a global ignore instead:
diff --git a/digest-keccak.gemspec b/digest-keccak.gemspec
index 5b1181b..be16608 100644
--- a/digest-keccak.gemspec
+++ b/digest-keccak.gemspec
@@ -11,6 +11,7 @@ Gem::Specification.new do |spec|
   spec.license  = 'MIT'
   spec.homepage = 'https://github.com/kotovalexarian/digest-keccak.rb'
   spec.summary  = 'The Keccak cryptographic hash function.'
+  spec.platform = Gem::Platform::RUBY
 
   spec.required_ruby_version = '~> 2.2'