diff --git a/build_tests/ruby.rb b/build_tests/ruby.rb
new file mode 100644
index 0000000..12af7fe
--- /dev/null
+++ b/build_tests/ruby.rb
@@ -0,0 +1,18 @@
+# ruby_check.sh runs this and verifies the output matches.
+# The first argument is the absolute path to the runfiles directory to use for
+# testing require with an absolute path.
+
+$loaded = false
+raise unless require_relative 'ruby_to_require.rb'
+raise unless $loaded
+
+# We already loaded this above, so it won't happen again.
+raise if require 'build_tests/ruby_to_require'
+
+$loaded = false
+raise unless require ARGV[0] + '/build_tests/ruby_to_require'
+raise unless $loaded
+
+raise unless ''.encoding == Encoding::UTF_8
+
+puts 'Hi from ruby'