diff --git a/.fixtures.yml b/.fixtures.yml
new file mode 100644
index 0000000..2cf24e8
--- /dev/null
+++ b/.fixtures.yml
@@ -0,0 +1,11 @@
+---
+fixtures:
+  repositories:
+    stdlib:
+      repo: https://github.com/puppetlabs/puppetlabs-stdlib.git
+      ref: v9.7.0
+    concat:
+      repo: https://github.com/puppetlabs/puppetlabs-concat.git
+      ref: v9.0.2
+  symlinks:
+    sysfs: "#{source_dir}"
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
new file mode 100644
index 0000000..d591d35
--- /dev/null
+++ b/.github/workflows/ci.yml
@@ -0,0 +1,54 @@
+name: CI
+
+on:
+  pull_request:
+    branches: [master, main]
+  push:
+    branches: [master, main]
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        ruby: ["3.1", "3.2", "3.3"]
+        puppet: ["~> 7.0", "~> 8.0"]
+        exclude:
+          - ruby: "3.3"
+            puppet: "~> 7.0"
+
+    env:
+      PUPPET_VERSION: ${{ matrix.puppet }}
+
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Set up Ruby ${{ matrix.ruby }}
+        uses: ruby/setup-ruby@v1
+        with:
+          ruby-version: ${{ matrix.ruby }}
+          bundler-cache: true
+
+      - name: Run tests
+        run: bundle exec rake spec
+
+  lint:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Set up Ruby
+        uses: ruby/setup-ruby@v1
+        with:
+          ruby-version: "3.2"
+          bundler-cache: true
+
+      - name: Run puppet-lint
+        run: bundle exec rake lint
+
+      - name: Validate metadata.json
+        run: bundle exec rake metadata_lint
+
+      - name: Validate manifests
+        run: bundle exec rake validate
diff --git a/.gitignore b/.gitignore
index 5fff1d9..9851e1c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1,11 @@
-pkg
+pkg/
+vendor/
+.bundle/
+Gemfile.lock
+spec/fixtures/
+.vagrant/
+*.swp
+*.swo
+.idea/
+.vscode/
+coverage/
diff --git a/.rspec b/.rspec
new file mode 100644
index 0000000..16f9cdb
--- /dev/null
+++ b/.rspec
@@ -0,0 +1,2 @@
+--color
+--format documentation
diff --git a/.rubocop.yml b/.rubocop.yml
new file mode 100644
index 0000000..89027d2
--- /dev/null
+++ b/.rubocop.yml
@@ -0,0 +1,24 @@
+---
+AllCops:
+  TargetRubyVersion: 2.6
+  NewCops: enable
+  Exclude:
+    - spec/fixtures/**/*
+    - pkg/**/*
+    - vendor/**/*
+
+Style/Documentation:
+  Enabled: false
+
+Metrics/BlockLength:
+  Exclude:
+    - spec/**/*
+
+Layout/LineLength:
+  Max: 140
+
+Style/HashSyntax:
+  EnforcedStyle: ruby19
+
+Style/StringLiterals:
+  EnforcedStyle: single_quotes
diff --git a/.ruby-version b/.ruby-version
new file mode 100644
index 0000000..15a2799
--- /dev/null
+++ b/.ruby-version
@@ -0,0 +1 @@
+3.3.0
diff --git a/Gemfile b/Gemfile
index 7bd34cd..f8216cc 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,7 +1,24 @@
 source 'https://rubygems.org'
 
-puppetversion = ENV.key?('PUPPET_VERSION') ? "= #{ENV['PUPPET_VERSION']}" : ['>= 3.3']
-gem 'puppet', puppetversion
-gem 'puppetlabs_spec_helper', '>= 0.1.0'
-gem 'puppet-lint', '>= 0.3.2'
-gem 'facter', '>= 1.7.0'
+puppet_version = ENV['PUPPET_VERSION']
+if puppet_version
+  gem 'puppet', puppet_version
+else
+  gem 'puppet', '>= 7.0'
+end
+gem 'facter', '>= 2.5'
+
+# Required for newer Ruby versions (removed from stdlib)
+gem 'logger'
+gem 'ostruct'
+gem 'bigdecimal'
+gem 'racc'
+gem 'base64'
+
+group :development, :test do
+  gem 'rake'
+  gem 'rspec-puppet', '~> 2.12'
+  gem 'puppetlabs_spec_helper', '~> 5.0'
+  gem 'puppet-lint', '~> 3.0'
+  gem 'metadata-json-lint'
+end
diff --git a/Rakefile b/Rakefile
index d1e11f7..8d637ab 100644
--- a/Rakefile
+++ b/Rakefile
@@ -1,18 +1,32 @@
 require 'rubygems'
 require 'puppetlabs_spec_helper/rake_tasks'
 require 'puppet-lint/tasks/puppet-lint'
+require 'metadata-json-lint/rake_task'
+
+# Puppet-lint configuration
 PuppetLint.configuration.send('disable_80chars')
-PuppetLint.configuration.ignore_paths = ["spec/**/*.pp", "pkg/**/*.pp"]
+PuppetLint.configuration.send('disable_140chars')
+PuppetLint.configuration.ignore_paths = ['spec/**/*.pp', 'pkg/**/*.pp', 'vendor/**/*.pp']
+PuppetLint.configuration.relative = true
 
-desc "Validate manifests, templates, and ruby files"
+desc 'Validate manifests, templates, and ruby files'
 task :validate do
   Dir['manifests/**/*.pp'].each do |manifest|
     sh "puppet parser validate --noop #{manifest}"
   end
-  Dir['spec/**/*.rb','lib/**/*.rb'].each do |ruby_file|
-    sh "ruby -c #{ruby_file}" unless ruby_file =~ /spec\/fixtures/
+  Dir['spec/**/*.rb', 'lib/**/*.rb'].each do |ruby_file|
+    sh "ruby -c #{ruby_file}" unless ruby_file =~ %r{spec/fixtures}
   end
   Dir['templates/**/*.erb'].each do |template|
     sh "erb -P -x -T '-' #{template} | ruby -c"
   end
 end
+
+desc 'Run all linting tasks'
+task lint_all: [:lint, :metadata_lint]
+
+desc 'Run all tests'
+task test: [:validate, :lint_all, :spec]
+
+# Default task
+task default: :test
diff --git a/metadata.json b/metadata.json
index 684c097..640d151 100644
--- a/metadata.json
+++ b/metadata.json
@@ -3,13 +3,50 @@
   "version": "0.2.0",
   "author": "danfoster",
   "summary": "A module for managing sysfs settings",
-  "license": "Apache 2.0",
+  "license": "Apache-2.0",
   "source": "https://github.com/danfoster/puppet-sysfs",
   "project_page": "https://github.com/danfoster/puppet-sysfs",
   "issues_url": "https://github.com/danfoster/puppet-sysfs/issues",
   "dependencies": [
-    {"name":"puppetlabs-stdlib","version_requirement":">= 1.0.0"},
-    {"name":"puppetlabs-concat"}
+    {
+      "name": "puppetlabs-stdlib",
+      "version_requirement": ">= 4.0.0 < 10.0.0"
+    },
+    {
+      "name": "puppetlabs-concat",
+      "version_requirement": ">= 4.0.0 < 10.0.0"
+    }
+  ],
+  "operatingsystem_support": [
+    {
+      "operatingsystem": "RedHat",
+      "operatingsystemrelease": ["7", "8", "9"]
+    },
+    {
+      "operatingsystem": "CentOS",
+      "operatingsystemrelease": ["7", "8"]
+    },
+    {
+      "operatingsystem": "AlmaLinux",
+      "operatingsystemrelease": ["8", "9"]
+    },
+    {
+      "operatingsystem": "Rocky",
+      "operatingsystemrelease": ["8", "9"]
+    },
+    {
+      "operatingsystem": "Debian",
+      "operatingsystemrelease": ["10", "11", "12"]
+    },
+    {
+      "operatingsystem": "Ubuntu",
+      "operatingsystemrelease": ["20.04", "22.04", "24.04"]
+    }
+  ],
+  "requirements": [
+    {
+      "name": "puppet",
+      "version_requirement": ">= 7.0.0 < 9.0.0"
+    }
   ]
 }
-
diff --git a/spec/classes/init_spec.rb b/spec/classes/init_spec.rb
deleted file mode 100644
index bc28aa0..0000000
--- a/spec/classes/init_spec.rb
+++ /dev/null
@@ -1,7 +0,0 @@
-require 'spec_helper'
-describe 'sysfs' do
-
-  context 'with defaults for all parameters' do
-    it { should contain_class('sysfs') }
-  end
-end
diff --git a/spec/classes/sysfs_spec.rb b/spec/classes/sysfs_spec.rb
new file mode 100644
index 0000000..ff98d4d
--- /dev/null
+++ b/spec/classes/sysfs_spec.rb
@@ -0,0 +1,184 @@
+require 'spec_helper'
+
+describe 'sysfs' do
+  context 'with default parameters' do
+    it { is_expected.to compile.with_all_deps }
+    it { is_expected.to contain_class('sysfs') }
+
+    # Package management
+    it { is_expected.to contain_package('sysfsutils').with_ensure('installed') }
+
+    # Configuration file
+    it do
+      is_expected.to contain_concat('/etc/sysfs.conf').with(
+        'owner' => 'root',
+        'group' => 'root',
+        'mode'  => '0644',
+        'force' => true,
+      )
+    end
+
+    it { is_expected.to contain_concat('/etc/sysfs.conf').that_requires('Package[sysfsutils]') }
+
+    # Service management
+    it do
+      is_expected.to contain_service('sysfsutils').with(
+        'ensure' => 'running',
+        'enable' => true,
+      )
+    end
+
+    it { is_expected.to contain_service('sysfsutils').that_subscribes_to('Concat[/etc/sysfs.conf]') }
+  end
+
+  context 'with settings parameter' do
+    let(:params) do
+      {
+        settings: {
+          'class/block/sda/queue/read_ahead_kb' => { 'value' => '256' },
+          'class/block/sdb/queue/rotational'    => { 'value' => '0' },
+        },
+      }
+    end
+
+    it { is_expected.to compile.with_all_deps }
+
+    it do
+      is_expected.to contain_sysfs__setting('class/block/sda/queue/read_ahead_kb').with(
+        'value' => '256',
+      )
+    end
+
+    it do
+      is_expected.to contain_sysfs__setting('class/block/sdb/queue/rotational').with(
+        'value' => '0',
+      )
+    end
+  end
+
+  # RedHat 7+ specific tests
+  context 'on RedHat 7+' do
+    let(:facts) do
+      {
+        os: {
+          'family' => 'RedHat',
+          'name' => 'CentOS',
+          'release' => {
+            'full' => '7.9',
+            'major' => '7',
+            'minor' => '9',
+          },
+        },
+        kernel: 'Linux',
+      }
+    end
+
+    it { is_expected.to compile.with_all_deps }
+
+    # Custom reload script for RHEL 7+
+    it do
+      is_expected.to contain_file('/usr/local/bin/sysfs-reload').with(
+        'source' => 'puppet:///modules/sysfs/sysfs-reload',
+        'owner'  => 'root',
+        'group'  => 'root',
+        'mode'   => '0700',
+      )
+    end
+
+    it { is_expected.to contain_file('/usr/local/bin/sysfs-reload').that_comes_before('File[/etc/systemd/system/sysfsutils.service]') }
+
+    # Systemd service unit
+    it do
+      is_expected.to contain_file('/etc/systemd/system/sysfsutils.service').with(
+        'source' => 'puppet:///modules/sysfs/sysfsutils.service',
+        'owner'  => 'root',
+        'group'  => 'root',
+        'mode'   => '0700',
+      )
+    end
+
+    it { is_expected.to contain_file('/etc/systemd/system/sysfsutils.service').that_comes_before('Service[sysfsutils]') }
+
+    # Exec for reloading sysfs settings
+    it do
+      is_expected.to contain_exec('sysfsutils_reload_rhel').with(
+        'refreshonly' => true,
+      )
+    end
+
+    it { is_expected.to contain_exec('sysfsutils_reload_rhel').that_subscribes_to('Concat[/etc/sysfs.conf]') }
+  end
+
+  context 'on RedHat 8+' do
+    let(:facts) do
+      {
+        os: {
+          'family' => 'RedHat',
+          'name' => 'AlmaLinux',
+          'release' => {
+            'full' => '8.5',
+            'major' => '8',
+            'minor' => '5',
+          },
+        },
+        kernel: 'Linux',
+      }
+    end
+
+    it { is_expected.to compile.with_all_deps }
+    it { is_expected.to contain_file('/usr/local/bin/sysfs-reload') }
+    it { is_expected.to contain_file('/etc/systemd/system/sysfsutils.service') }
+    it { is_expected.to contain_exec('sysfsutils_reload_rhel') }
+  end
+
+  context 'on RedHat 6 (pre-systemd)' do
+    let(:facts) do
+      {
+        os: {
+          'family' => 'RedHat',
+          'name' => 'CentOS',
+          'release' => {
+            'full' => '6.10',
+            'major' => '6',
+            'minor' => '10',
+          },
+        },
+        kernel: 'Linux',
+      }
+    end
+
+    it { is_expected.to compile.with_all_deps }
+    it { is_expected.not_to contain_file('/usr/local/bin/sysfs-reload') }
+    it { is_expected.not_to contain_file('/etc/systemd/system/sysfsutils.service') }
+    it { is_expected.not_to contain_exec('sysfsutils_reload_rhel') }
+  end
+
+  context 'on Debian' do
+    let(:facts) do
+      {
+        os: {
+          'family' => 'Debian',
+          'name' => 'Ubuntu',
+          'release' => {
+            'full' => '22.04',
+            'major' => '22',
+            'minor' => '04',
+          },
+        },
+        kernel: 'Linux',
+      }
+    end
+
+    it { is_expected.to compile.with_all_deps }
+
+    # Should NOT have RHEL-specific resources
+    it { is_expected.not_to contain_file('/usr/local/bin/sysfs-reload') }
+    it { is_expected.not_to contain_file('/etc/systemd/system/sysfsutils.service') }
+    it { is_expected.not_to contain_exec('sysfsutils_reload_rhel') }
+
+    # Should still have common resources
+    it { is_expected.to contain_package('sysfsutils') }
+    it { is_expected.to contain_service('sysfsutils') }
+    it { is_expected.to contain_concat('/etc/sysfs.conf') }
+  end
+end
diff --git a/spec/defines/setting_spec.rb b/spec/defines/setting_spec.rb
new file mode 100644
index 0000000..a56c6f2
--- /dev/null
+++ b/spec/defines/setting_spec.rb
@@ -0,0 +1,119 @@
+require 'spec_helper'
+
+describe 'sysfs::setting' do
+  let(:pre_condition) { 'include sysfs' }
+
+  let(:facts) do
+    {
+      os: {
+        'family' => 'RedHat',
+        'name' => 'CentOS',
+        'release' => {
+          'full' => '8.0',
+          'major' => '8',
+          'minor' => '0',
+        },
+      },
+      kernel: 'Linux',
+    }
+  end
+
+  context 'with a simple setting' do
+    let(:title) { 'class/block/sda/queue/read_ahead_kb' }
+    let(:params) { { value: '256' } }
+
+    it { is_expected.to compile.with_all_deps }
+
+    it do
+      is_expected.to contain_concat__fragment('class/block/sda/queue/read_ahead_kb').with(
+        'target'  => '/etc/sysfs.conf',
+        'content' => "class/block/sda/queue/read_ahead_kb=256\n",
+      )
+    end
+  end
+
+  context 'with rotational setting' do
+    let(:title) { 'class/block/sdb/queue/rotational' }
+    let(:params) { { value: '0' } }
+
+    it { is_expected.to compile.with_all_deps }
+
+    it do
+      is_expected.to contain_concat__fragment('class/block/sdb/queue/rotational').with(
+        'target'  => '/etc/sysfs.conf',
+        'content' => "class/block/sdb/queue/rotational=0\n",
+      )
+    end
+  end
+
+  context 'with scheduler setting' do
+    let(:title) { 'block/sda/queue/scheduler' }
+    let(:params) { { value: 'deadline' } }
+
+    it { is_expected.to compile.with_all_deps }
+
+    it do
+      is_expected.to contain_concat__fragment('block/sda/queue/scheduler').with(
+        'target'  => '/etc/sysfs.conf',
+        'content' => "block/sda/queue/scheduler=deadline\n",
+      )
+    end
+  end
+
+  context 'with numeric value' do
+    let(:title) { 'kernel/mm/transparent_hugepage/enabled' }
+    let(:params) { { value: 'never' } }
+
+    it { is_expected.to compile.with_all_deps }
+
+    it do
+      is_expected.to contain_concat__fragment('kernel/mm/transparent_hugepage/enabled').with(
+        'target'  => '/etc/sysfs.conf',
+        'content' => "kernel/mm/transparent_hugepage/enabled=never\n",
+      )
+    end
+  end
+
+  context 'with integer value' do
+    let(:title) { 'class/net/eth0/queues/rx-0/rps_cpus' }
+    let(:params) { { value: 15 } }
+
+    it { is_expected.to compile.with_all_deps }
+
+    it do
+      is_expected.to contain_concat__fragment('class/net/eth0/queues/rx-0/rps_cpus').with(
+        'target'  => '/etc/sysfs.conf',
+        'content' => "class/net/eth0/queues/rx-0/rps_cpus=15\n",
+      )
+    end
+  end
+
+  context 'on Debian' do
+    let(:facts) do
+      {
+        os: {
+          'family' => 'Debian',
+          'name' => 'Ubuntu',
+          'release' => {
+            'full' => '22.04',
+            'major' => '22',
+            'minor' => '04',
+          },
+        },
+        kernel: 'Linux',
+      }
+    end
+
+    let(:title) { 'class/block/sda/queue/nr_requests' }
+    let(:params) { { value: '128' } }
+
+    it { is_expected.to compile.with_all_deps }
+
+    it do
+      is_expected.to contain_concat__fragment('class/block/sda/queue/nr_requests').with(
+        'target'  => '/etc/sysfs.conf',
+        'content' => "class/block/sda/queue/nr_requests=128\n",
+      )
+    end
+  end
+end
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index 2c6f566..297a152 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -1 +1,24 @@
 require 'puppetlabs_spec_helper/module_spec_helper'
+
+RSpec.configure do |c|
+  c.default_facts = {
+    os: {
+      'family' => 'RedHat',
+      'name' => 'CentOS',
+      'release' => {
+        'full' => '8.0',
+        'major' => '8',
+        'minor' => '0',
+      },
+    },
+    osfamily: 'RedHat',
+    operatingsystem: 'CentOS',
+    operatingsystemrelease: '8.0',
+    kernel: 'Linux',
+  }
+
+  c.before(:each) do
+    Puppet::Util::Log.level = :warning
+    Puppet::Util::Log.newdestination(:console)
+  end
+end