diff --git a/README.md b/README.md
index 2edd6e7..fd8be44 100644
--- a/README.md
+++ b/README.md
@@ -25,6 +25,10 @@ Or install it yourself as:
 gem install berns
 ```
 
+*Note:* Berns is only tested on Ruby's MRI/CRuby interpreter version 2.7 and
+greater. Berns version 3.x and below support Ruby 2.5. Contributions are welcome
+to get JRuby or TruffleRuby working.
+
 ## Usage
 
 Note that all return string values will be UTF-8 encoded.
diff --git a/berns.gemspec b/berns.gemspec
index 27c7493..8eca8fb 100644
--- a/berns.gemspec
+++ b/berns.gemspec
@@ -11,7 +11,7 @@ Gem::Specification.new do |spec|
   spec.description = spec.summary
   spec.homepage = 'https://github.com/evanleck/berns'
   spec.license = 'MIT'
-  spec.required_ruby_version = '>= 2.5.0'
+  spec.required_ruby_version = '>= 2.7.0'
   spec.required_rubygems_version = '>= 2.0'
 
   spec.files = Dir['ext/**/*', 'lib/**/*', 'README.md', 'LICENSE.txt']