Gemfile in groupify-0.6.2 vs Gemfile in groupify-0.6.3

@@ -9,7 +9,17 @@
 end
 
 # Specify your gem's dependencies in groupify.gemspec
 gemspec
 
-gem "jdbc-sqlite3", platform: :jruby
-gem "activerecord-jdbcsqlite3-adapter", platform: :jruby
+platforms :jruby do
+  gem "activerecord-jdbcsqlite3-adapter"
+  gem "activerecord-jdbcmysql-adapter"
+  gem "jdbc-mysql"
+  gem "activerecord-jdbcpostgresql-adapter"
+end
+
+platforms :ruby do
+  gem "sqlite3"
+  gem "mysql2"
+  gem "pg"
+end