diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 19740af..5e2510b 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -19,7 +19,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ruby: [2.6, 2.7, '3.0', 3.1, 3.2, ruby-head, jruby]
+        ruby: ['3.0', 3.1, 3.2, ruby-head, jruby]
     steps:
       - name: Clone repository
         uses: actions/checkout@v3
@@ -33,6 +33,6 @@ jobs:
         run: ruby --version; bundle exec rspec spec || $ALLOW_FAILURES
       - name: Coveralls GitHub Action
         uses: coverallsapp/github-action@master
-        if: "matrix.ruby == '3.0'"
+        if: "matrix.ruby == '3.2'"
         with:
           github-token: ${{ secrets.GITHUB_TOKEN }}
diff --git a/Gemfile b/Gemfile
index da9c0df..f131e6c 100644
--- a/Gemfile
+++ b/Gemfile
@@ -2,7 +2,7 @@ source "https://rubygems.org"
 gemspec
 
 group :development, :test do
-  gem 'simplecov', '~> 0.21',  platforms: :mri
+  gem 'simplecov', '~> 0.22',  platforms: :mri
   gem 'simplecov-lcov', '~> 0.8',  platforms: :mri
   gem 'benchmark-ips'
   gem 'rake'
diff --git a/README.md b/README.md
index ddbf512..be3e793 100644
--- a/README.md
+++ b/README.md
@@ -3,7 +3,7 @@ An implementation of the JSON Canonicalization Scheme for Ruby
 
 Implements [RFC8785](https://datatracker.ietf.org/doc/html/rfc8785) (JSON Canonicalization Scheme) in Ruby.
 
-[![Gem Version](https://badge.fury.io/rb/json-canonicalization.png)](http://badge.fury.io/rb/json-canonicalization)
+[![Gem Version](https://badge.fury.io/rb/json-canonicalization.svg)](http://badge.fury.io/rb/json-canonicalization)
 [![Build Status](https://github.com/dryruby/json-canonicalization/workflows/CI/badge.svg?branch=develop)](https://github.com/dryruby/json-canonicalization/actions?query=workflow%3ACI)
 [![Coverage Status](https://coveralls.io/repos/dryruby/json-canonicalization/badge.svg)](https://coveralls.io/r/dryruby/json-canonicalization)
 
@@ -66,7 +66,7 @@ Full documentation available on [GitHub](https://dryruby.github.io/json-canonica
 * {JSON::Canonicalization}
 
 ## Dependencies
-* [Ruby](http://ruby-lang.org/) (>= 2.6)
+* [Ruby](http://ruby-lang.org/) (>= 3.0)
 * [JSON](https://rubygems.org/gems/json) (>= 2.6)
 
 ## Author
diff --git a/VERSION b/VERSION
index d15723f..3eefcb9 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-0.3.2
+1.0.0
diff --git a/json-canonicalization.gemspec b/json-canonicalization.gemspec
index b27f811..c09b2d0 100755
--- a/json-canonicalization.gemspec
+++ b/json-canonicalization.gemspec
@@ -23,9 +23,9 @@ Gem::Specification.new do |gem|
   gem.files                 = %w(AUTHORS README.md LICENSE VERSION) + Dir.glob('lib/**/*.rb')
   gem.test_files            = Dir.glob('spec/**/*.rb') + Dir.glob('spec/**/*.json')
 
-  gem.required_ruby_version = '>= 2.6'
+  gem.required_ruby_version = '>= 3.0'
   gem.requirements          = []
-  gem.add_development_dependency 'rspec',           '~> 3.10'
+  gem.add_development_dependency 'rspec',           '~> 3.12'
   gem.add_development_dependency 'yard' ,           '~> 0.9'
 
   gem.post_install_message  = nil