diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index f475deb..1c88477 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -20,10 +20,10 @@ jobs:
       fail-fast: false
       matrix:
         ruby:
-          - 2.5
           - 2.6
           - 2.7
           - 3.0
+          - 3.1
           - ruby-head
           - jruby
     steps:
diff --git a/README.md b/README.md
index 578064f..8c0ce2e 100644
--- a/README.md
+++ b/README.md
@@ -14,7 +14,7 @@ This version is based on [rack-linkeddata][] without the hard dependency on the
 ## Features
 
 * Implements [HTTP content negotiation][conneg] for RDF content types using
-  the [`Rack::RDF`][Rack::RDF] middleware.
+  the `[Rack::RDF][Rack::RDF]` middleware.
 * Supports all [RDF.rb][] -compatible serialization formats.
 * Supports both classic and modular Sinatra applications.
 
@@ -92,7 +92,7 @@ run My::Application
 ## Description
 
 `Sinatra::RDF` is a thin Sinatra-specific wrapper around the
-[`Rack::RDF`][Rack::RDF] middleware, which implements Linked
+`[Rack::RDF][Rack::RDF]` middleware, which implements Linked
 Data content negotiation for Rack applications.
 
 At the moment the Sinatra extension simply corresponds
@@ -119,8 +119,8 @@ operation and details of the content negotiation.
 
 ## Dependencies
 
-* [Sinatra](https://rubygems.org/gems/sinatra) (~> 2.0)
-* [Rack::RDF](https://rubygems.org/gems/rack-rdf) (~> 3.1)
+* [Sinatra](https://rubygems.org/gems/sinatra) (~> 2.1)
+* [Rack::RDF](https://rubygems.org/gems/rack-rdf) (~> 3.2)
 
 ## Installation
 
diff --git a/VERSION b/VERSION
index ef538c2..944880f 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-3.1.2
+3.2.0
diff --git a/sinatra-rdf.gemspec b/sinatra-rdf.gemspec
index 5274ef7..8c5a428 100755
--- a/sinatra-rdf.gemspec
+++ b/sinatra-rdf.gemspec
@@ -20,9 +20,9 @@ Gem::Specification.new do |gem|
   gem.executables        = %w()
   gem.require_paths      = %w(lib)
 
-  gem.required_ruby_version      = '>= 2.4'
+  gem.required_ruby_version      = '>= 2.6'
   gem.requirements               = []
-  gem.add_runtime_dependency     'rack-rdf',        '~> 3.1', '>= 3.1.2'
+  gem.add_runtime_dependency     'rack-rdf',        '~> 3.2'
   gem.add_runtime_dependency     'sinatra',         '~> 2.1'
 
   gem.add_development_dependency 'yard' ,           '~> 0.9'