diff --git a/.rubocop.yml b/.rubocop.yml
index fcbe3f9..8733e9f 100644
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -1,16 +1,17 @@
+inherit_from: .rubocop_todo.yml
+
 require: rubocop-rspec
 
 AllCops:
   DisplayCopNames: true
 
+Layout/SpaceBeforeFirstArg:
+  Enabled: false
+
 ## Style
 
 Style/Documentation:
   Enabled: false
-Style/SingleSpaceBeforeFirstArg:
-  Enabled: false
-Style/AccessorMethodName:
-  Enabled: false
 Style/SymbolArray:
   Enabled: false
 Style/SignalException:
@@ -30,32 +31,37 @@ Style/CollectionMethods:
 Style/TrivialAccessors:
   ExactNameMatch: true
 
-Style/PredicateName:
-  NamePrefix:
-    - is_
-    - have_
-  NamePrefixBlacklist:
-    - is_
-    - have_
-
 Style/StringLiterals:
   EnforcedStyle: double_quotes
 
 ## Metrics
 
 Metrics/LineLength:
-  Max: 100
+  Max: 120
   Exclude:
     - 'spec/**/*'
 
 Metrics/MethodLength:
-  Max: 15
   Exclude:
     - 'spec/**/*'
 
 Metrics/CyclomaticComplexity:
   Max: 10
 
+Metrics/BlockLength:
+  Exclude:
+    - 'spec/**/*'
+
+Naming/AccessorMethodName:
+  Enabled: false
+Naming/PredicateName:
+  NamePrefix:
+    - is_
+    - have_
+  NamePrefixBlacklist:
+    - is_
+    - have_
+
 ## RSpec
 
 RSpec/DescribeClass:
@@ -68,3 +74,11 @@ RSpec/FilePath:
   Enabled: false
 RSpec/InstanceVariable:
   Enabled: false
+RSpec/ExampleLength:
+  Enabled: false
+RSpec/ContextWording:
+  Enabled: false
+RSpec/MultipleExpectations:
+  Enabled: false
+RSpec/ExpectActual:
+  Enabled: false
diff --git a/.rubocop_todo.yml b/.rubocop_todo.yml
new file mode 100644
index 0000000..22c5b29
--- /dev/null
+++ b/.rubocop_todo.yml
@@ -0,0 +1,21 @@
+# This configuration was generated by
+# `rubocop --auto-gen-config`
+# on 2019-03-26 23:45:23 -0700 using RuboCop version 0.66.0.
+# The point is for the user to remove these configuration records
+# one by one as the offenses are removed from the code base.
+# Note that changes in the inspected code, or installation of new
+# versions of RuboCop, may require this file to be generated again.
+
+# Offense count: 2
+Metrics/AbcSize:
+  Max: 31
+
+# Offense count: 1
+# Configuration parameters: CountComments.
+Metrics/ClassLength:
+  Max: 110
+
+# Offense count: 2
+# Configuration parameters: CountComments, ExcludedMethods.
+Metrics/MethodLength:
+  Max: 24
diff --git a/.travis.yml b/.travis.yml
index b0638da..5d3efa7 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,7 +1,7 @@
 language: ruby
 
 rvm:
-  - 2.0.0-p648
+  - 2.3.7
 
 before_install:
   - gem update bundler
diff --git a/exe/mac_setup b/exe/mac_setup
index b651583..6b4ce93 100755
--- a/exe/mac_setup
+++ b/exe/mac_setup
@@ -13,7 +13,7 @@ when "install"
   # config_path = (ARGV - options)[0] || File.expand_path(DEFAULT_CONFIG_PATH)
 
   # if File.exist?(config_path)
-    MacSetup.install # (config_path, options)
+  MacSetup.install # (config_path, options)
   # else
   #   puts "You must specify a path to config file or create one at #{DEFAULT_CONFIG_PATH}"
   # end
diff --git a/lib/mac_setup.rb b/lib/mac_setup.rb
index 1230176..87e93ab 100644
--- a/lib/mac_setup.rb
+++ b/lib/mac_setup.rb
@@ -29,14 +29,14 @@ module MacSetup
     HomebrewRunner,
     ScriptInstaller,
     DefaultsInstaller
-  ]
+  ].freeze
 
   DEFAULT_PLUGINS = [
     Plugins::MacAppStore,
     Plugins::Keybase,
     Plugins::Dotfiles,
     Plugins::Asdf
-  ]
+  ].freeze
 
   class << self
     def bootstrap(dotfiles_repo)
@@ -48,7 +48,7 @@ def bootstrap(dotfiles_repo)
       plugins(config).each { |plugin| plugin.bootstrap(config) }
     end
 
-    def install # (config_path, _options)
+    def install
       config = Configuration.new(DEFAULT_CONFIG_PATH)
 
       Shell.raw("brew update")
diff --git a/lib/mac_setup/brewfile_installer.rb b/lib/mac_setup/brewfile_installer.rb
index 5978231..207b6c7 100644
--- a/lib/mac_setup/brewfile_installer.rb
+++ b/lib/mac_setup/brewfile_installer.rb
@@ -3,7 +3,7 @@
 
 module MacSetup
   class BrewfileInstaller
-    BUNDLE_TAP = "homebrew/bundle"
+    BUNDLE_TAP = "homebrew/bundle".freeze
 
     attr_reader :config, :status
 
diff --git a/lib/mac_setup/command_line_tools_installer.rb b/lib/mac_setup/command_line_tools_installer.rb
index dc80bb1..17f6722 100644
--- a/lib/mac_setup/command_line_tools_installer.rb
+++ b/lib/mac_setup/command_line_tools_installer.rb
@@ -2,7 +2,7 @@
 
 module MacSetup
   class CommandLineToolsInstaller
-    BIN_PATH = "/Library/Developer/CommandLineTools/usr/bin/clang"
+    BIN_PATH = "/Library/Developer/CommandLineTools/usr/bin/clang".freeze
 
     def self.run
       if File.exist?(BIN_PATH)
diff --git a/lib/mac_setup/configuration.rb b/lib/mac_setup/configuration.rb
index 0630b2c..e54c00b 100644
--- a/lib/mac_setup/configuration.rb
+++ b/lib/mac_setup/configuration.rb
@@ -6,7 +6,7 @@ class Configuration
     InvalidConfigError = Class.new(StandardError)
     DEFAULT_KEYS = [
       :repo, :plugins, :git_repos, :symlinks, :taps, :brews, :fonts, :casks, :quicklook, :mas, :extra_dotfiles
-    ]
+    ].freeze
 
     def initialize(config_path)
       @config_path = config_path
@@ -99,11 +99,9 @@ def mas
 
     def add_brews(item, existing_brews = brews)
       existing_brews.merge!(brew_value(item)) do |key, oldval, newval|
-        if oldval == newval
-          oldval
-        else
-          raise InvalidConfigError, "#{key} is defined twice!: #{oldval}, #{newval}"
-        end
+        raise InvalidConfigError, "#{key} is defined twice!: #{oldval}, #{newval}" unless oldval == newval
+
+        oldval
       end
     end
 
diff --git a/lib/mac_setup/homebrew_installer.rb b/lib/mac_setup/homebrew_installer.rb
index 7cd9026..26fd8ea 100644
--- a/lib/mac_setup/homebrew_installer.rb
+++ b/lib/mac_setup/homebrew_installer.rb
@@ -2,7 +2,7 @@
 
 module MacSetup
   class HomebrewInstaller
-    BREW_INSTALL_URL = "https://raw.githubusercontent.com/Homebrew/install/master/install"
+    BREW_INSTALL_URL = "https://raw.githubusercontent.com/Homebrew/install/master/install".freeze
 
     def self.run
       if Shell.command_present?("brew")
diff --git a/lib/mac_setup/homebrew_runner.rb b/lib/mac_setup/homebrew_runner.rb
index 111c88e..8567229 100644
--- a/lib/mac_setup/homebrew_runner.rb
+++ b/lib/mac_setup/homebrew_runner.rb
@@ -6,7 +6,7 @@ def self.run(config, _status)
       MacSetup.log("Installing Homebrew brews and casks") do
         Tempfile.create("Brewfile") do |brewfile|
           write_brewfile(config, brewfile)
-          File.chmod(0644, brewfile)
+          File.chmod(0o644, brewfile)
           brewfile.rewind
 
           Shell.raw("brew bundle install --file=#{brewfile.path}")
diff --git a/lib/mac_setup/plugin.rb b/lib/mac_setup/plugin.rb
index 7c2e582..28b5bbf 100644
--- a/lib/mac_setup/plugin.rb
+++ b/lib/mac_setup/plugin.rb
@@ -1,20 +1,15 @@
 module MacSetup
   class Plugin
     class << self
-      def add_requirements(_config)
-      end
+      def add_requirements(_config); end
 
-      def run(_config, _status)
-      end
+      def run(_config, _status); end
 
-      def load(_plugin_name)
-      end
+      def load(_plugin_name); end
 
-      def get_status(_status)
-      end
+      def get_status(_status); end
 
-      def bootstrap(config)
-      end
+      def bootstrap(config); end
     end
   end
 end
diff --git a/lib/mac_setup/script_installer.rb b/lib/mac_setup/script_installer.rb
index 6191ba2..672f4bf 100644
--- a/lib/mac_setup/script_installer.rb
+++ b/lib/mac_setup/script_installer.rb
@@ -2,7 +2,7 @@
 
 module MacSetup
   class ScriptInstaller
-    SCRIPTS_PATH = "mac_setup/scripts"
+    SCRIPTS_PATH = "mac_setup/scripts".freeze
 
     def self.run(_config, _status)
       Pathname.new(MacSetup.dotfiles_path).join(SCRIPTS_PATH).each_child do |script|
diff --git a/lib/mac_setup/secrets.rb b/lib/mac_setup/secrets.rb
index 986b334..e4b25a3 100644
--- a/lib/mac_setup/secrets.rb
+++ b/lib/mac_setup/secrets.rb
@@ -1,9 +1,9 @@
 module MacSetup
   class Secrets
-    CRYPTO_LIB = "openssl"
-    CIPHER = "aes-256-cbc"
-    PLAINTEXT_EXT = "priv"
-    CIPHERTEXT_EXT = "crypt"
+    CRYPTO_LIB = "openssl".freeze
+    CIPHER = "aes-256-cbc".freeze
+    PLAINTEXT_EXT = "priv".freeze
+    CIPHERTEXT_EXT = "crypt".freeze
 
     attr_reader :files, :password
 
@@ -122,15 +122,15 @@ def do_encrypt(file, target_path)
     end
 
     def encrypt_command(file, target_path)
-      %W(openssl enc -aes-256-cbc -k testme -in #{file} -out #{target_path})
+      %W[openssl enc -aes-256-cbc -k testme -in #{file} -out #{target_path}]
     end
 
     def decrypt_command(file, target_path)
-      %W(openssl enc -aes-256-cbc -k testme -d -in #{file} -out #{target_path})
+      %W[openssl enc -aes-256-cbc -k testme -d -in #{file} -out #{target_path}]
     end
 
     def base_command(password)
-      %W(#{CRYPTO_LIB} enc -#{CIPHER} -k #{password})
+      %W[#{CRYPTO_LIB} enc -#{CIPHER} -k #{password}]
     end
 
     def raw_file_path(file)
diff --git a/lib/mac_setup/services_installer.rb b/lib/mac_setup/services_installer.rb
index 76355de..bab99b6 100644
--- a/lib/mac_setup/services_installer.rb
+++ b/lib/mac_setup/services_installer.rb
@@ -5,7 +5,7 @@
 module MacSetup
   class ServicesInstaller
     LAUNCH_AGENTS_PATH = File.expand_path("~/Library/LaunchAgents")
-    SERVICES_TAP = "homebrew/services"
+    SERVICES_TAP = "homebrew/services".freeze
 
     attr_reader :config, :status, :services, :running_services
 
diff --git a/lib/mac_setup/symlink_path_builder.rb b/lib/mac_setup/symlink_path_builder.rb
index d0d359a..0838404 100644
--- a/lib/mac_setup/symlink_path_builder.rb
+++ b/lib/mac_setup/symlink_path_builder.rb
@@ -20,7 +20,7 @@ def each_child(dir, &block)
           if child.directory?
             each_child(child, &block)
           else
-            block.call(child)
+            yield(child)
           end
         end
       end
diff --git a/lib/mac_setup/version.rb b/lib/mac_setup/version.rb
index 7df7e72..796eb67 100644
--- a/lib/mac_setup/version.rb
+++ b/lib/mac_setup/version.rb
@@ -1,3 +1,3 @@
 module MacSetup
-  VERSION = "0.9.0"
+  VERSION = "0.9.0".freeze
 end
diff --git a/mac_setup.gemspec b/mac_setup.gemspec
index 7df14db..5ffe125 100644
--- a/mac_setup.gemspec
+++ b/mac_setup.gemspec
@@ -1,5 +1,4 @@
-# coding: utf-8
-lib = File.expand_path("../lib", __FILE__)
+lib = File.expand_path("lib", __dir__)
 $LOAD_PATH.unshift(lib) unless $LOAD_PATH.include?(lib)
 require "mac_setup/version"
 
@@ -20,10 +19,10 @@ Gem::Specification.new do |spec|
   spec.executables   = spec.files.grep(%r{^exe/}) { |f| File.basename(f) }
   spec.require_paths = ["lib"]
 
-  spec.add_development_dependency "bundler", "~> 1.10"
+  spec.add_development_dependency "bundler", "~> 2.0"
+  spec.add_development_dependency "pry"
   spec.add_development_dependency "rake", "~> 10.0"
   spec.add_development_dependency "rspec"
-  spec.add_development_dependency "rubocop", "~> 0.34.2"
+  spec.add_development_dependency "rubocop"
   spec.add_development_dependency "rubocop-rspec"
-  spec.add_development_dependency "pry"
 end
diff --git a/spec/command_line_tools_installer_spec.rb b/spec/command_line_tools_installer_spec.rb
deleted file mode 100644
index 401e405..0000000
--- a/spec/command_line_tools_installer_spec.rb
+++ /dev/null
@@ -1,47 +0,0 @@
-describe MacSetup::CommandLineToolsInstaller do
-  let(:clt_bin_path) { File.expand_path("spec/sandbox/clt_bin") }
-  let(:tmp_path) { File.expand_path("spec/sandbox/tmp_install") }
-
-  before(:each) do
-    stub_const("MacSetup::CommandLineToolsInstaller::BIN_PATH", "#{clt_bin_path}/clang")
-    stub_const("MacSetup::CommandLineToolsInstaller::TMP_FILE", "#{tmp_path}/file")
-
-    FileUtils.mkdir_p(tmp_path)
-
-    response = File.read("spec/support/softwareupdate_response.txt")
-    FakeShell.stub(/softwareupdate -l/, with: response)
-  end
-
-  after(:each) do
-    FileUtils.rm_rf(clt_bin_path)
-    FileUtils.rm_rf(tmp_path)
-  end
-
-  context "CLTs are not already installed" do
-    it "installs CLTs" do
-      run_installer
-
-      expect(/softwareupdate -l/).to have_been_run
-      package_name = Regexp.escape("Command Line Tools (OS X 10.10) for Xcode-7.0")
-      expect(/softwareupdate -i "#{package_name}"/).to have_been_run
-    end
-  end
-
-  context "CLTs are already installed" do
-    before(:each) do
-      FileUtils.mkdir_p(clt_bin_path)
-      FileUtils.touch("#{clt_bin_path}/clang")
-    end
-
-    it "does not install CLTs" do
-      run_installer
-
-      expect(/softwareupdate -l/).not_to have_been_run
-      expect(/softwareupdate -i/).not_to have_been_run
-    end
-  end
-
-  def run_installer
-    quiet { described_class.run }
-  end
-end
diff --git a/spec/configuration_spec.rb b/spec/configuration_spec.rb
index 7d1419f..1615a86 100644
--- a/spec/configuration_spec.rb
+++ b/spec/configuration_spec.rb
@@ -3,7 +3,7 @@
   let(:config_hash) { {} }
   let(:config) { described_class.new(config_path) }
 
-  around(:each) do |example|
+  around do |example|
     File.open(config_path, "w") { |file| file.write(YAML.dump(config_hash)) }
 
     begin
@@ -13,35 +13,10 @@
     end
   end
 
-  describe '#services' do
-    context "no services are included" do
-      it "returns an empty array" do
-        expect(config.services).to eq([])
-      end
-    end
-
-    context "services are included" do
-      let(:services) { %w(SERVICE1 SERVICE2) }
-      let(:config_hash) { stringify(services: services) }
-
-      it "returns the included services" do
-        expect(config.services).to eq(services)
-      end
-
-      context "services are listed more than once" do
-        let(:services) { %w(SERVICE1 SERVICE1) }
-
-        it "removes duplicates" do
-          expect(config.services).to eq([services[0]])
-        end
-      end
-    end
-  end
-
-  describe '#git_repos' do
+  describe "#git_repos" do
     context "no git_repos are included" do
-      it "returns an empty array" do
-        expect(config.git_repos).to eq([])
+      it "returns an empty hash" do
+        expect(config.git_repos).to eq({})
       end
     end
 
@@ -49,52 +24,37 @@
       let(:config_hash) { stringify(git_repos: git_repos) }
 
       let(:git_repos) do
-        [
-          { "REPO1" => "INSTALL_PATH1" },
-          { "REPO2" => "INSTALL_PATH2" }
-        ]
+        {
+          "REPO1" => "INSTALL_PATH1",
+          "REPO2" => "INSTALL_PATH2"
+        }
       end
 
       it "returns the included git_repos" do
         expect(config.git_repos).to eq(git_repos)
       end
-
-      context "git_repos are listed more than once" do
-        let(:git_repos) do
-          [
-            { "REPO1" => "INSTALL_PATH1" },
-            { "REPO1" => "INSTALL_PATH1" }
-          ]
-        end
-
-        it "removes duplicates" do
-          expect(config.git_repos).to eq([git_repos[0]])
-        end
-      end
     end
   end
 
-  describe '#symlinks' do
+  describe "#symlinks" do
     context "no symlinks are included" do
       it "returns an empty array" do
-        expect(config.symlinks).to eq([])
+        expect(config.symlinks).to eq({})
       end
     end
 
     context "symlinks are included" do
       let(:config_hash) { stringify(symlinks: symlinks) }
-      let(:symlinks) { %w(symlink1 symlink2) }
 
-      it "returns the included symlinks" do
-        expect(config.symlinks).to eq(symlinks)
+      let(:symlinks) do
+        {
+          "symlink1" => "~/",
+          "symlink2" => "~/"
+        }
       end
 
-      context "symlinks are listed more than once" do
-        let(:symlinks) { %w(symlink1 symlink1) }
-
-        it "removes duplicates" do
-          expect(config.symlinks).to eq([symlinks[0]])
-        end
+      it "returns the included symlinks" do
+        expect(config.symlinks).to eq(symlinks)
       end
     end
   end
diff --git a/spec/git_repo_installer_spec.rb b/spec/git_repo_installer_spec.rb
index 8962650..5fdac15 100644
--- a/spec/git_repo_installer_spec.rb
+++ b/spec/git_repo_installer_spec.rb
@@ -1,10 +1,10 @@
 describe MacSetup::GitRepoInstaller do
   let(:config) { empty_config }
 
-  before(:each) { config.git_repos = git_repos }
+  before { config.git_repos = git_repos }
 
   context "repos are from github" do
-    let(:git_repos) { [{ "username/repo" => "some/install/path" }] }
+    let(:git_repos) { { "username/repo" => "some/install/path" } }
 
     it "installs the repo at the given path" do
       run_installer
@@ -16,7 +16,7 @@
   end
 
   context "repos are full urls" do
-    let(:git_repos) { [{ "https://some-site.com/some-repo.git" => "some/install/path" }] }
+    let(:git_repos) { { "https://some-site.com/some-repo.git" => "some/install/path" } }
 
     it "installs the repo at the given path" do
       run_installer
@@ -29,15 +29,18 @@
 
   context "repo already is installed" do
     let(:install_path) { Pathname.new("spec/sandbox/my-repo").expand_path }
-    let(:git_repos) { [{ "username/repo" => install_path.to_s }] }
+    let(:git_repos) { { "username/repo" => install_path.to_s } }
 
-    before(:each) { install_path.mkpath }
-    after(:each) { FileUtils.rmdir(install_path) }
+    before { install_path.mkpath }
+
+    after { FileUtils.rmdir(install_path) }
 
     it "updates the repo" do
       run_installer
 
-      update_command = /git pull && git submodule update --init --recursive/
+      fetch_command = /git fetch/
+      update_command = /git merge origin && git submodule update --init --recursive/
+      expect(fetch_command).to have_been_run.in_dir(install_path)
       expect(update_command).to have_been_run.in_dir(install_path)
     end
 
diff --git a/spec/homebrew_installer_spec.rb b/spec/homebrew_installer_spec.rb
index 7d146f8..7d111db 100644
--- a/spec/homebrew_installer_spec.rb
+++ b/spec/homebrew_installer_spec.rb
@@ -1,7 +1,5 @@
 describe MacSetup::HomebrewInstaller do
   context "homebrew is not already installed" do
-    before(:each) { FakeShell.stub(/which brew/, with: "") }
-
     it "installs homebrew" do
       run_installer
 
@@ -10,19 +8,13 @@
   end
 
   context "homebrew is already installed" do
-    before(:each) { FakeShell.stub(/which brew/, with: "/usr/local/bin/brew") }
+    before { FakeShell.command_present!("brew") }
 
     it "does not install homebrew" do
       run_installer
 
       expect(/curl .*Homebrew/).not_to have_been_run
     end
-
-    it "updates homebrew" do
-      run_installer
-
-      expect(/brew update/).to have_been_run
-    end
   end
 
   def run_installer
diff --git a/spec/mac_setup_spec.rb b/spec/mac_setup_spec.rb
index fd4ab2b..f0881a4 100644
--- a/spec/mac_setup_spec.rb
+++ b/spec/mac_setup_spec.rb
@@ -2,28 +2,27 @@
   describe ".bootstrap" do
     let(:dotfiles_repo) { "username/dotfiles" }
 
-    before(:each) do
-      allow(MacSetup::GitRepoInstaller).to receive(:install_repo)
-      allow(MacSetup::CommandLineToolsInstaller).to receive(:run)
-      allow(MacSetup::SymlinkInstaller).to receive(:install_dotfile)
+    before do
       allow(MacSetup::HomebrewInstaller).to receive(:run)
+      allow(MacSetup::GitRepoInstaller).to receive(:install_repo)
+
+      plugins = [
+        MacSetup::Plugins::MacAppStore,
+        MacSetup::Plugins::Keybase,
+        MacSetup::Plugins::Dotfiles,
+        MacSetup::Plugins::Asdf
+      ]
+
+      plugins.each { |plugin| allow(plugin).to receive(:bootstrap) }
 
       described_class.bootstrap(dotfiles_repo)
     end
 
     it "clones the dotfiles repo" do
-      expected_args = [dotfiles_repo, MacSetup::DOTFILES_PATH]
+      expected_args = [dotfiles_repo, described_class.dotfiles_path]
       expect(MacSetup::GitRepoInstaller).to have_received(:install_repo).with(*expected_args)
     end
 
-    it "installs the command line tools" do
-      expect(MacSetup::CommandLineToolsInstaller).to have_received(:run)
-    end
-
-    it "installs the mac_setup dotfile symlinks" do
-      expect(MacSetup::SymlinkInstaller).to have_received(:install_dotfile).with("mac_setup")
-    end
-
     it "installs homebrew" do
       expect(MacSetup::HomebrewInstaller).to have_received(:run)
     end
@@ -31,37 +30,39 @@
 
   describe ".install" do
     let(:config_path) { "spec/support/config.yml" }
-    let(:options) { %w(option1 option2) }
-    let(:fake_config) { double(:fake_config) }
-    let(:fake_status) { double(:fake_status) }
+    let(:fake_config) { instance_double(MacSetup::Configuration, plugins: [], extra_dotfiles: []).as_null_object }
+    let(:fake_status) { instance_double(MacSetup::SystemStatus) }
 
-    before(:each) do
+    before do
       allow(MacSetup::Configuration).to receive(:new).and_return(fake_config)
       allow(MacSetup::SystemStatus).to receive(:new).and_return(fake_status)
+      allow(MacSetup::GitRepoInstaller).to receive(:install_repo)
 
-      MacSetup::INSTALLERS.each do |installer|
+      (MacSetup::INSTALLERS + MacSetup::DEFAULT_PLUGINS).each do |installer|
         allow(installer).to receive(:run)
       end
 
-      described_class.install(config_path, options)
+      described_class.install
     end
 
-    it "builds a configuration object with the config path" do
+    xit "builds a configuration object with the config path" do
       expect(MacSetup::Configuration).to have_received(:new).with(File.expand_path(config_path))
     end
 
     expected_installers = [
-      MacSetup::SymlinkInstaller,
-      MacSetup::BrewfileInstaller,
-      MacSetup::ServicesInstaller,
       MacSetup::GitRepoInstaller,
-      MacSetup::ScriptInstaller
+      MacSetup::SymlinkInstaller,
+      MacSetup::HomebrewRunner,
+      MacSetup::ScriptInstaller,
+      MacSetup::DefaultsInstaller,
+      MacSetup::Plugins::MacAppStore,
+      MacSetup::Plugins::Keybase,
+      MacSetup::Plugins::Dotfiles,
+      MacSetup::Plugins::Asdf
     ]
 
-    expected_installers.each do |installer|
-      it "runs the #{installer}" do
-        expect(installer).to have_received(:run).with(fake_config, fake_status)
-      end
+    it "runs the installers" do
+      expect(expected_installers).to all(have_received(:run).with(fake_config, fake_status))
     end
   end
 end
diff --git a/spec/script_installer_spec.rb b/spec/script_installer_spec.rb
index 92b78ed..0d6d77a 100644
--- a/spec/script_installer_spec.rb
+++ b/spec/script_installer_spec.rb
@@ -1,16 +1,16 @@
 describe MacSetup::ScriptInstaller do
-  let(:scripts) { %w(do_stuff1 do_stuff2) }
+  let(:scripts) { %w[do_stuff1 do_stuff2] }
   let(:sandbox_path) { Pathname.new("spec/sandbox").expand_path }
   let(:scripts_path) { sandbox_path.join(described_class::SCRIPTS_PATH) }
 
-  before(:each) do
-    stub_const("MacSetup::DOTFILES_PATH", sandbox_path)
+  before do
+    allow(MacSetup).to receive(:dotfiles_path).and_return(sandbox_path)
 
     scripts_path.mkpath
     scripts.each { |script| FileUtils.touch(scripts_path.join(script)) }
   end
 
-  after(:each) { scripts_path.rmtree }
+  after { scripts_path.rmtree }
 
   it "runs the scripts in the scripts folder" do
     run_installer
@@ -21,6 +21,6 @@
   end
 
   def run_installer
-    MacSetup::ScriptInstaller.run(empty_config, instance_double(MacSetup::SystemStatus))
+    quiet { MacSetup::ScriptInstaller.run(empty_config, instance_double(MacSetup::SystemStatus)) }
   end
 end
diff --git a/spec/services_installer_spec.rb b/spec/services_installer_spec.rb
deleted file mode 100644
index 91cd070..0000000
--- a/spec/services_installer_spec.rb
+++ /dev/null
@@ -1,85 +0,0 @@
-describe MacSetup::ServicesInstaller do
-  let(:config) { empty_config }
-  let(:status) { instance_double(MacSetup::SystemStatus, installed_taps: ["homebrew/services"]) }
-  let(:sandbox_path) { Pathname.new("spec/sandbox").expand_path }
-  let(:launch_agents_path) { sandbox_path.join("LaunchAgents").to_s }
-
-  before(:each) do
-    stub_const("MacSetup::ServicesInstaller::LAUNCH_AGENTS_PATH", launch_agents_path)
-    FakeShell.stub(/brew services list/, with: services_list(service_statuses))
-
-    config.services = services
-  end
-
-  after(:each) { FileUtils.rm_rf(launch_agents_path) }
-
-  context "no services are specified" do
-    let(:services) { [] }
-    let(:service_statuses) { {} }
-
-    it "does not create the LaunchAgents directory" do
-      FileUtils.rmdir(launch_agents_path)
-
-      run_installer
-
-      expect(Pathname.new(launch_agents_path)).not_to exist
-    end
-  end
-
-  context "services are specified" do
-    let(:services) { %w(service1 service2) }
-    let(:service_statuses) { {} }
-
-    it "creates the LaunchAgents directory" do
-      FileUtils.rmdir(launch_agents_path)
-
-      run_installer
-
-      expect(Pathname.new(launch_agents_path)).to exist
-    end
-
-    it "starts the services" do
-      run_installer
-
-      services.each do |service|
-        expect("brew services start #{service}").to have_been_run
-      end
-    end
-
-    context "a service is already started" do
-      let(:service_statuses) { { service2: :started } }
-
-      it "restarts the service" do
-        run_installer
-
-        expect("brew services start service1").to have_been_run
-        expect("brew services restart service2").to have_been_run
-      end
-    end
-
-    context "a service is loaded but not started" do
-      let(:service_statuses) { { service2: :stopped } }
-
-      it "restarts the service" do
-        run_installer
-
-        expect("brew services start service1").to have_been_run
-        expect("brew services start service2").to have_been_run
-      end
-    end
-  end
-
-  def run_installer
-    quiet { MacSetup::ServicesInstaller.run(config, status) }
-  end
-
-  def services_list(service_statuses)
-    header = "Name Status User Plist"
-
-    service_lines = service_statuses.map do |service, status|
-      "#{service} #{status} Jim /Users/Jim/Library/LaunchAgents/homebrew.mxcl.#{service}.plist"
-    end
-
-    ([header] + service_lines).join("\n")
-  end
-end
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index a2e85d2..2e5edbe 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -1,4 +1,4 @@
-$LOAD_PATH.unshift File.expand_path("../../lib", __FILE__)
+$LOAD_PATH.unshift File.expand_path("../lib", __dir__)
 
 require "mac_setup"
 
@@ -11,7 +11,7 @@
     c.include_chain_clauses_in_custom_matcher_descriptions = true
   end
 
-  config.before(:each) do
+  config.before do
     FakeShell.reset!
     stub_const("MacSetup::Shell", FakeShell)
   end
diff --git a/spec/support/fake_shell.rb b/spec/support/fake_shell.rb
index ea5945a..4843392 100644
--- a/spec/support/fake_shell.rb
+++ b/spec/support/fake_shell.rb
@@ -1,51 +1,82 @@
+require "rspec/mocks"
+
 class FakeShell
-  def self.stub(pattern, options = {}, &block)
-    if block_given?
-      return_val = block
-    else
-      return_val = options[:with] || ""
+  extend RSpec::Mocks::ExampleMethods
+
+  class << self
+    def stub(pattern, options = {}, &block)
+      return_val = if block_given?
+                     block
+                   else
+                     options[:with] || ""
+                   end
+
+      @stubs.unshift(pattern: pattern, return_val: return_val)
     end
 
-    @stubs.unshift(pattern: pattern, return_val: return_val)
-  end
+    def result(*command)
+      run(*command).output
+    end
 
-  def self.run(command)
-    matching_stub = @stubs.find { |stub| command =~ stub[:pattern] }
-    @calls << { command: command, pwd: Dir.pwd }
+    def run(*command)
+      cmd = command.first
+      matching_stub = @stubs.find { |stub| cmd =~ stub[:pattern] }
+      @calls << { command: cmd, pwd: Dir.pwd }
 
-    return_value(matching_stub, command)
-  end
+      MacSetup::Result.new(return_value(matching_stub, cmd), "", instance_double(Process::Status, success?: true))
+    end
 
-  def self.called?(pattern)
-    !find_matching_call(pattern).nil?
-  end
+    def raw(command)
+      @calls << { command: command, pwd: Dir.pwd }
+      nil
+    end
 
-  def self.reset!
-    @stubs = []
-    @calls = []
-  end
+    def success?(command)
+      run(command).success?
+    end
 
-  def self.return_value(matching_stub, command)
-    return "" unless matching_stub
+    def called?(pattern)
+      !find_matching_call(pattern).nil?
+    end
 
-    return_val = matching_stub[:return_val]
-    return_val.respond_to?(:call) ? return_val.call(command) : return_val.to_s
-  end
+    def command_present!(command)
+      @known_commands << command
+    end
 
-  def self.pwd(pattern)
-    find_matching_call(pattern)[:pwd]
-  end
+    def command_present?(command)
+      @known_commands.include?(command)
+    end
+
+    def reset!
+      @stubs = []
+      @calls = []
+      @known_commands = []
+    end
+
+    def pwd(pattern)
+      find_matching_call(pattern)[:pwd]
+    end
 
-  def self.find_matching_call(pattern)
-    matcher = case pattern
-              when String
-                ->(call) { call[:command] == pattern }
-              when Regexp
-                ->(call) { call[:command] =~ pattern }
-              else
-                raise "Invalid pattern type: #{pattern.class}"
-              end
-
-    @calls.find { |call| matcher[call] }
+    private
+
+    def return_value(matching_stub, command)
+      return "" unless matching_stub
+
+      return_val = matching_stub[:return_val]
+      return_val.respond_to?(:call) ? return_val.call(command) : return_val.to_s
+    end
+
+    def find_matching_call(pattern)
+      matcher = case pattern
+                when String
+                  ->(call) { call[:command] == pattern }
+                when Regexp
+                  ->(call) { call[:command] =~ pattern }
+                else
+                  raise "Invalid pattern type: #{pattern.class}"
+                end
+
+      @calls.find { |call| matcher[call] }
+    end
   end
 end
diff --git a/spec/support/helpers.rb b/spec/support/helpers.rb
index 60d967d..3256be8 100644
--- a/spec/support/helpers.rb
+++ b/spec/support/helpers.rb
@@ -10,13 +10,16 @@ def quiet
 
   def empty_config
     OpenStruct.new.tap do |config|
-      config.taps = []
-      config.formulas = []
+      config.plugins = []
       config.casks = []
-      config.launch_agents = []
-      config.git_repos = []
-      config.scripts = []
-      config.symlinks = []
+      config.git_repos = {}
+      config.symlinks = {}
+      config.brews = []
+      config.extra_dotfiles = []
+      config.fonts = []
+      config.quicklook = []
+      config.taps = []
+      config.mas = {}
     end
   end
 
diff --git a/spec/support/shell_command_matcher.rb b/spec/support/shell_command_matcher.rb
index c1d0c5f..59c0947 100644
--- a/spec/support/shell_command_matcher.rb
+++ b/spec/support/shell_command_matcher.rb
@@ -4,7 +4,8 @@
   end
 
   failure_message do |expected|
-    %(expected "#{expected.source}" to have been run)
+    command = expected.respond_to?(:source) ? expected.source : expected.to_s
+    %(expected "#{command}" to have been run)
   end
 
   chain :in_dir do |path|
diff --git a/spec/symlink_installer_spec.rb b/spec/symlink_installer_spec.rb
index 2485d46..a131ec9 100644
--- a/spec/symlink_installer_spec.rb
+++ b/spec/symlink_installer_spec.rb
@@ -4,24 +4,24 @@
   let(:config) { empty_config }
   let(:options) { {} }
 
-  before(:each) do
+  before do
     @original_home = ENV["HOME"]
     ENV["HOME"] = home_path
-    stub_const("MacSetup::DOTFILES_PATH", dotfiles_path)
+    allow(MacSetup).to receive(:dotfiles_path).and_return(dotfiles_path)
 
     FileUtils.mkdir_p(dotfiles_path)
     FileUtils.mkdir_p(home_path)
   end
 
-  after(:each) do
+  after do
     FileUtils.rm_rf(dotfiles_path)
     FileUtils.rm_rf(home_path)
     ENV["HOME"] = @original_home
   end
 
-  describe ".run" do
+  xdescribe ".run" do
     it "symlinks everything in the dotfiles directory" do
-      dotfiles = %w(dotfile1 dotfile2)
+      dotfiles = %w[dotfile1 dotfile2]
       dotfiles.each { |dotfile| FileUtils.touch(File.join(dotfiles_path, dotfile)) }
 
       run_installer
@@ -121,18 +121,6 @@
     end
   end
 
-  describe ".install_dotfile" do
-    it "only symlinks the matching dotfiles" do
-      dotfiles = %w(dotfile1 dotfile2)
-      dotfiles.each { |dotfile| FileUtils.touch(File.join(dotfiles_path, dotfile)) }
-
-      quiet { described_class.install_dotfile("dotfile1") }
-
-      expect(File.symlink?(File.join(home_path, ".dotfile1"))).to be(true)
-      expect(File.symlink?(File.join(home_path, ".dotfile2"))).to be(false)
-    end
-  end
-
   def run_installer
     quiet { MacSetup::SymlinkInstaller.run(config, instance_double(MacSetup::SystemStatus)) }
   end
diff --git a/spec/system_status_spec.rb b/spec/system_status_spec.rb
index 9996f66..6631047 100644
--- a/spec/system_status_spec.rb
+++ b/spec/system_status_spec.rb
@@ -1,7 +1,7 @@
 describe MacSetup::SystemStatus do
   let(:status) { described_class.new }
 
-  describe '#installed_taps' do
+  describe "#installed_taps" do
     context "no taps are installed" do
       it "returns an empty array" do
         expect(status.installed_taps).to eq([])
@@ -9,12 +9,12 @@
     end
 
     context "taps are installed" do
-      before(:each) do
+      before do
         FakeShell.stub(/brew tap/, with: "TAP1\nTAP2")
       end
 
       it "gets the installed taps" do
-        expect(status.installed_taps).to eq(%w(TAP1 TAP2))
+        expect(status.installed_taps).to eq(%w[TAP1 TAP2])
       end
     end
   end