diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 43a21e9cb..a41403ed2 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -31,7 +31,7 @@ jobs:
   ruby-mutant:
     name: Mutation coverage
     runs-on: ${{ matrix.os }}
-    timeout-minutes: 5
+    timeout-minutes: 30
     strategy:
       fail-fast: false
       matrix:
@@ -47,7 +47,7 @@ jobs:
     - run: |
         gem install bundler
         bundle install
-    - run: bundle exec mutant --since HEAD~1 --zombie -- 'Mutant*'
+    - run: ./mutant.sh
   ruby-integration-minitest:
     name: Integration Minitest
     runs-on: ${{ matrix.os }}
diff --git a/lib/mutant/ast.rb b/lib/mutant/ast.rb
index b5b58e534..477b40e47 100644
--- a/lib/mutant/ast.rb
+++ b/lib/mutant/ast.rb
@@ -27,15 +27,6 @@ def self.find_last_path(node, &predicate)
       path
     end
 
-    # Walk all ast nodes keeping track of path
-    #
-    # @param [Parser::AST::Node] root
-    # @param [Array<Parser::AST::Node>] stack
-    #
-    # @yield [Parser::AST::Node]
-    #   all nodes visited recursively including root
-    #
-    # @return [undefined]
     def self.walk(node, stack, &block)
       block.call(node, stack)
       node.children.grep(::Parser::AST::Node) do |child|
diff --git a/lib/mutant/ast/meta/send.rb b/lib/mutant/ast/meta/send.rb
index 6f4b40d41..41a2c9e08 100644
--- a/lib/mutant/ast/meta/send.rb
+++ b/lib/mutant/ast/meta/send.rb
@@ -56,16 +56,10 @@ def receiver_possible_top_level_const?
 
       private
 
-        # Test if node is `proc { ... }`
-        #
-        # @return [Boolean]
         def naked_proc?
           !receiver && selector.equal?(:proc)
         end
 
-        # Test if node is `Proc.new { ... }`
-        #
-        # @return [Boolean]
         def proc_new?
           receiver                &&
             selector.equal?(:new) &&
diff --git a/lib/mutant/bootstrap.rb b/lib/mutant/bootstrap.rb
index 7d89348a2..1fd02da5d 100644
--- a/lib/mutant/bootstrap.rb
+++ b/lib/mutant/bootstrap.rb
@@ -49,9 +49,6 @@ def self.apply(world, config)
     end
     # rubocop:enable Metrics/MethodLength
 
-    # Infect environment
-    #
-    # @return [undefined]
     def self.infect(env)
       config, world = env.config, env.world
 
@@ -60,12 +57,6 @@ def self.infect(env)
     end
     private_class_method :infect
 
-    # Matchable scopes
-    #
-    # @param [World] world
-    # @param [Config] config
-    #
-    # @return [Array<Scope>]
     def self.matchable_scopes(world, config)
       scopes = world.object_space.each_object(Module).each_with_object([]) do |scope, aggregate|
         expression = expression(config.reporter, config.expression_parser, scope) || next
@@ -76,15 +67,6 @@ def self.matchable_scopes(world, config)
     end
     private_class_method :matchable_scopes
 
-    # Scope name from scoping object
-    #
-    # @param [Class, Module] scope
-    #
-    # @return [String]
-    #   if scope has a name and does not raise exceptions obtaining it
-    #
-    # @return [nil]
-    #   otherwise
     def self.scope_name(reporter, scope)
       scope.name
     rescue => exception
@@ -99,20 +81,7 @@ def self.scope_name(reporter, scope)
     end
     private_class_method :scope_name
 
-    # Try to turn scope into expression
-    #
-    # @param [Expression::Parser] expression_parser
-    # @param [Class, Module] scope
-    #
-    # @return [Expression]
-    #   if scope can be represented in an expression
-    #
-    # @return [nil]
-    #   otherwise
-    #
     # rubocop:disable Metrics/MethodLength
-    #
-    # ignore :reek:LongParameterList
     def self.expression(reporter, expression_parser, scope)
       name = scope_name(reporter, scope) or return
 
@@ -132,11 +101,6 @@ def self.expression(reporter, expression_parser, scope)
     private_class_method :expression
     # rubocop:enable Metrics/MethodLength
 
-    # Write a semantics warning
-    #
-    # @return [undefined]
-    #
-    # ignore :reek:LongParameterList
     def self.semantics_warning(reporter, format, options)
       reporter.warn(SEMANTICS_MESSAGE_FORMAT % { message: format % options })
     end
diff --git a/lib/mutant/cli.rb b/lib/mutant/cli.rb
index 7679c78fd..1869c4ca2 100644
--- a/lib/mutant/cli.rb
+++ b/lib/mutant/cli.rb
@@ -88,23 +88,12 @@ def parse(arguments)
 
   private
 
-    # Parse matchers
-    #
-    # @param [Array<String>] expressions
-    #
-    # @return [undefined]
     def parse_match_expressions(expressions)
       expressions.each do |expression|
         add_matcher(:match_expressions, config.expression_parser.apply(expression).from_right)
       end
     end
 
-    # Add environmental options
-    #
-    # @param [Object] opts
-    #
-    # @return [undefined]
-    #
     # rubocop:disable Metrics/MethodLength
     def add_environment_options(opts)
       opts.separator('Environment:')
@@ -121,12 +110,8 @@ def add_environment_options(opts)
         with(jobs: Integer(number))
       end
     end
+    # rubocop:enable Metrics/MethodLength
 
-    # Add mutation options
-    #
-    # @param [OptionParser] opts
-    #
-    # @return [undefined]
     def add_mutation_options(opts)
       opts.separator(nil)
       opts.separator('Options:')
@@ -136,11 +121,7 @@ def add_mutation_options(opts)
       end
     end
 
-    # Add filter options
-    #
-    # @param [OptionParser] opts
-    #
-    # @return [undefined]
+    # rubocop:disable Metrics/MethodLength
     def add_filter_options(opts)
       opts.on('--ignore-subject EXPRESSION', 'Ignore subjects that match EXPRESSION as prefix') do |pattern|
         add_matcher(:ignore_expressions, config.expression_parser.apply(pattern).from_right)
@@ -154,12 +135,9 @@ def add_filter_options(opts)
         )
       end
     end
+    # rubocop:enable Metrics/MethodLength
 
-    # Add debug options
-    #
-    # @param [OptionParser] opts
-    #
-    # @return [undefined]
+    # rubocop:disable Metrics/MethodLength
     def add_debug_options(opts)
       opts.on('--fail-fast', 'Fail fast') do
         with(fail_fast: true)
@@ -173,38 +151,16 @@ def add_debug_options(opts)
         world.kernel.exit
       end
     end
+    # rubocop:enable Metrics/MethodLength
 
-    # With configuration
-    #
-    # @param [Hash<Symbol, Object>] attributes
-    #
-    # @return [undefined]
     def with(attributes)
       @config = config.with(attributes)
     end
 
-    # Add configuration
-    #
-    # @param [Symbol] attribute
-    #   the attribute to add to
-    #
-    # @param [Object] value
-    #   the value to add
-    #
-    # @return [undefined]
     def add(attribute, value)
       with(attribute => config.public_send(attribute) + [value])
     end
 
-    # Add matcher configuration
-    #
-    # @param [Symbol] attribute
-    #   the attribute to add to
-    #
-    # @param [Object] value
-    #   the value to add
-    #
-    # @return [undefined]
     def add_matcher(attribute, value)
       with(matcher: config.matcher.add(attribute, value))
     end
diff --git a/lib/mutant/color.rb b/lib/mutant/color.rb
index 25e76a5c7..85336751d 100644
--- a/lib/mutant/color.rb
+++ b/lib/mutant/color.rb
@@ -28,9 +28,6 @@ def format(text)
 
     private
 
-      # Initialize null color
-      #
-      # @return [undefined]
       def initialize; end
 
     end.new
diff --git a/lib/mutant/config.rb b/lib/mutant/config.rb
index 4359cf65f..62436ce66 100644
--- a/lib/mutant/config.rb
+++ b/lib/mutant/config.rb
@@ -126,14 +126,6 @@ def self.load_config_file(world, config)
       end
     end
 
-    # Load contents of file
-    #
-    # @param [Pathname] path
-    #
-    # @return [Config]
-    #
-    # @raise [Either<String, Hash{Symbol => Object}>]
-    #   in case of config file error
     def self.load_contents(path)
       Transform::Named
         .new(path.to_s, TRANSFORM)
diff --git a/lib/mutant/context.rb b/lib/mutant/context.rb
index b9e2abbf0..f3a6f52ae 100644
--- a/lib/mutant/context.rb
+++ b/lib/mutant/context.rb
@@ -81,9 +81,6 @@ def match_expressions
 
   private
 
-    # Nesting of names in scope
-    #
-    # @return [Array<String>]
     def name_nesting
       scope.name.split(NAMESPACE_DELIMITER)
     end
diff --git a/lib/mutant/diff.rb b/lib/mutant/diff.rb
index 950e3b876..22719d5e7 100644
--- a/lib/mutant/diff.rb
+++ b/lib/mutant/diff.rb
@@ -58,25 +58,16 @@ def self.lines(source)
 
   private
 
-    # Diffs between old and new
-    #
-    # @return [Array<Array>]
     def diffs
       ::Diff::LCS.diff(old, new)
     end
 
-    # Raw diff-lcs hunks
-    #
-    # @return [Array<Diff::LCS::Hunk>]
     def hunks
       diffs.map do |diff|
         ::Diff::LCS::Hunk.new(old.map(&:dup), new, diff, max_length, 0)
       end
     end
 
-    # Minimized hunk
-    #
-    # @return Diff::LCS::Hunk
     def minimized_hunk
       head, *tail = hunks
 
@@ -86,18 +77,10 @@ def minimized_hunk
       end
     end
 
-    # Max length of source line in new and old
-    #
-    # @return [Integer]
     def max_length
       [old, new].map(&:length).max
     end
 
-    # Colorized a unified diff line
-    #
-    # @param [String] line
-    #
-    # @return [String]
     def self.colorize_line(line)
       case line[0]
       when ADDITION
diff --git a/lib/mutant/env.rb b/lib/mutant/env.rb
index 3ffb767a2..5569510cb 100644
--- a/lib/mutant/env.rb
+++ b/lib/mutant/env.rb
@@ -126,12 +126,6 @@ def test_subject_ratio
 
   private
 
-    # Kill mutation under isolation with integration
-    #
-    # @param [Mutation] mutation
-    # @param [Array<Test>] test
-    #
-    # @return [Result::Isolation]
     def run_mutation_tests(mutation, tests)
       config.isolation.call do
         result = mutation.insert(world.kernel)
diff --git a/lib/mutant/expression/method.rb b/lib/mutant/expression/method.rb
index bcc46a740..8a35489f9 100644
--- a/lib/mutant/expression/method.rb
+++ b/lib/mutant/expression/method.rb
@@ -46,9 +46,6 @@ def matcher
 
     private
 
-      # Scope object
-      #
-      # @return [Class, Method]
       def scope
         Object.const_get(scope_name)
       end
diff --git a/lib/mutant/expression/methods.rb b/lib/mutant/expression/methods.rb
index 05489fd6a..0e10af420 100644
--- a/lib/mutant/expression/methods.rb
+++ b/lib/mutant/expression/methods.rb
@@ -50,9 +50,6 @@ def match_length(expression)
 
     private
 
-      # Scope object
-      #
-      # @return [Class, Method]
       def scope
         Object.const_get(scope_name)
       end
diff --git a/lib/mutant/expression/parser.rb b/lib/mutant/expression/parser.rb
index 9935c6a20..2b8f40c0a 100644
--- a/lib/mutant/expression/parser.rb
+++ b/lib/mutant/expression/parser.rb
@@ -28,12 +28,6 @@ def apply(input)
 
     private
 
-      # Expressions parsed from input
-      #
-      # @param [String] input
-      #
-      # @return [Array<Expression>]
-      #   if expressions can be parsed from input
       def expressions(input)
         types.each_with_object([]) do |type, aggregate|
           expression = type.try_parse(input) and aggregate << expression
diff --git a/lib/mutant/integration.rb b/lib/mutant/integration.rb
index 0102eaf09..c3121ba48 100644
--- a/lib/mutant/integration.rb
+++ b/lib/mutant/integration.rb
@@ -32,14 +32,6 @@ def self.setup(env)
         .fmap { |klass| klass.new(env.config).setup }
     end
 
-    # Attempt to require integration
-    #
-    # @param env [Bootstrap]
-    #
-    # @return [Either<String, undefined>]
-    #
-    # @api private
-    #
     # rubocop:disable Style/MultilineBlockChain
     def self.attempt_require(env)
       integration_name = env.config.integration
@@ -56,13 +48,6 @@ def self.attempt_require(env)
     private_class_method :attempt_require
     # rubocop:enable Style/MultilineBlockChain
 
-    # Attempt const get
-    #
-    # @param env [Boostrap]
-    #
-    # @return [Either<String, Class<Integration>>]
-    #
-    # @api private
     def self.attempt_const_get(env)
       integration_name = env.config.integration
       constant_name    = integration_name.capitalize
@@ -98,9 +83,6 @@ def setup
 
   private
 
-    # Expression parser
-    #
-    # @return [Expression::Parser]
     def expression_parser
       config.expression_parser
     end
diff --git a/lib/mutant/integration/minitest.rb b/lib/mutant/integration/minitest.rb
index 2b3cc2a6b..f7befbe21 100644
--- a/lib/mutant/integration/minitest.rb
+++ b/lib/mutant/integration/minitest.rb
@@ -115,9 +115,6 @@ def all_tests
 
     private
 
-      # The index of all tests to runnable test cases
-      #
-      # @return [Hash<Test,TestCase>]
       def all_tests_index
         all_test_cases.each_with_object({}) do |test_case, index|
           index[construct_test(test_case)] = test_case
diff --git a/lib/mutant/integration/rspec.rb b/lib/mutant/integration/rspec.rb
index 7519aa20b..d7377daf9 100644
--- a/lib/mutant/integration/rspec.rb
+++ b/lib/mutant/integration/rspec.rb
@@ -80,9 +80,6 @@ def all_tests
 
     private
 
-      # Index of available tests
-      #
-      # @return [Hash<Test, RSpec::Core::Example]
       def all_tests_index
         all_examples.each_with_index.each_with_object({}) do |(example, example_index), index|
           index[parse_example(example, example_index)] = example
@@ -90,12 +87,6 @@ def all_tests_index
       end
       memoize :all_tests_index
 
-      # Parse example into test
-      #
-      # @param [RSpec::Core::Example] example
-      # @param [Integer] index
-      #
-      # @return [Test]
       def parse_example(example, index)
         metadata = example.metadata
 
@@ -111,11 +102,6 @@ def parse_example(example, index)
         )
       end
 
-      # Parse metadata into expression
-      #
-      # @param [RSpec::Core::Example::MetaData] metadata
-      #
-      # @return [Expression]
       def parse_metadata(metadata)
         if metadata.key?(:mutant_expression)
           parse_expression(metadata.fetch(:mutant_expression))
@@ -125,30 +111,16 @@ def parse_metadata(metadata)
         end
       end
 
-      # Parse expression
-      #
-      # @param [String] input
-      # @param [Proc] default
-      #
-      # @return [Expression]
       def parse_expression(input, &default)
         expression_parser.apply(input).from_right(&default)
       end
 
-      # Available rspec examples
-      #
-      # @return [Array<String, RSpec::Core::Example]
       def all_examples
         @world.example_groups.flat_map(&:descendants).flat_map(&:examples).select do |example|
           example.metadata.fetch(:mutant, true)
         end
       end
 
-      # Filter examples
-      #
-      # @param [#call] predicate
-      #
-      # @return [undefined]
       def filter_examples(&predicate)
         @world.filtered_examples.each_value do |examples|
           examples.keep_if(&predicate)
diff --git a/lib/mutant/isolation/fork.rb b/lib/mutant/isolation/fork.rb
index 3697a9db3..f9f6b8840 100644
--- a/lib/mutant/isolation/fork.rb
+++ b/lib/mutant/isolation/fork.rb
@@ -73,9 +73,6 @@ def call
 
       private
 
-        # Start child process
-        #
-        # @return [Integer]
         def start_child
           world.process.fork do
             Child.call(
@@ -87,12 +84,6 @@ def start_child
           end
         end
 
-        # Read child result
-        #
-        # @param [Integer] pid
-        #
-        # @return [undefined]
-        #
         # rubocop:disable Metrics/MethodLength
         def read_child_result(pid)
           result_fragments = []
@@ -115,11 +106,6 @@ def read_child_result(pid)
         end
         # rubocop:enable Metrics/MethodLength
 
-        # Read fragments
-        #
-        # @param [Hash{FD => Array<String}] targets
-        #
-        # @return [undefined]
         def read_fragments(targets)
           until targets.empty?
             ready, = world.io.select(targets.keys)
@@ -134,11 +120,6 @@ def read_fragments(targets)
           end
         end
 
-        # Wait for child process
-        #
-        # @param [Integer] pid
-        #
-        # @return [undefined]
         def wait_child(pid, log_fragments)
           _pid, status = world.process.wait2(pid)
 
@@ -147,9 +128,6 @@ def wait_child(pid, log_fragments)
           end
         end
 
-        # Add a result
-        #
-        # @param [Result]
         def add_result(result)
           @result = defined?(@result) ? @result.add_error(result) : result
         end
diff --git a/lib/mutant/matcher.rb b/lib/mutant/matcher.rb
index 3d84fc169..fa4e0f3ba 100644
--- a/lib/mutant/matcher.rb
+++ b/lib/mutant/matcher.rb
@@ -25,25 +25,11 @@ def self.from_config(config)
       )
     end
 
-    # Test if subject is allowed do
-    #
-    # @param [Config] config
-    # @param [Subject] subject
-    #
-    # @return [Boolean]
     def self.allowed_subject?(config, subject)
       select_subject?(config, subject) && !ignore_subject?(config, subject)
     end
     private_class_method :allowed_subject?
 
-    # Predicate that tests for selected subject
-    #
-    # @param [Config] config
-    # @param [Subject] subject
-    #
-    # @return [Boolean]
-    #
-    # @api private
     def self.select_subject?(config, subject)
       config.subject_filters.all? { |filter| filter.call(subject) }
     end
diff --git a/lib/mutant/matcher/config.rb b/lib/mutant/matcher/config.rb
index 3909e95ce..d906b4db5 100644
--- a/lib/mutant/matcher/config.rb
+++ b/lib/mutant/matcher/config.rb
@@ -44,16 +44,10 @@ def add(attribute, value)
 
     private
 
-      # Present attributes
-      #
-      # @return [Array<Symbol>]
       def present_attributes
         to_h.reject { |_key, value| value.empty? }.keys
       end
 
-      # Formatted attributes
-      #
-      # @return [String]
       def inspect_attributes
         attributes = present_attributes
           .map(&method(:format_attribute))
@@ -62,11 +56,6 @@ def inspect_attributes
         attributes.empty? ? EMPTY_ATTRIBUTES : attributes
       end
 
-      # Format attribute
-      #
-      # @param [Symbol] attribute_name
-      #
-      # @return [String]
       def format_attribute(attribute_name)
         ATTRIBUTE_FORMAT %
           [
diff --git a/lib/mutant/matcher/method.rb b/lib/mutant/matcher/method.rb
index 814001209..d3573938e 100644
--- a/lib/mutant/matcher/method.rb
+++ b/lib/mutant/matcher/method.rb
@@ -49,9 +49,6 @@ def call
 
       private
 
-        # Test if method should be skipped
-        #
-        # @return [Truthy]
         def skip?
           location = source_location
           if location.nil? || BLACKLIST.include?(location.first)
@@ -61,56 +58,31 @@ def skip?
           end
         end
 
-        # Target method name
-        #
-        # @return [String]
         def method_name
           target_method.name
         end
 
-        # Target context
-        #
-        # @return [Context]
         def context
           Context.new(scope, source_path)
         end
 
-        # Root source node
-        #
-        # @return [Parser::AST::Node]
         def ast
           env.parser.call(source_path)
         end
 
-        # Path to source
-        #
-        # @return [Pathname]
         def source_path
           env.world.pathname.new(source_location.first)
         end
         memoize :source_path
 
-        # Source file line
-        #
-        # @return [Integer]
         def source_line
           source_location.last
         end
 
-        # Full source location
-        #
-        # @return [Array{String,Integer}]
         def source_location
           target_method.source_location
         end
 
-        # Matched subject
-        #
-        # @return [Subject]
-        #   if there is a matched node
-        #
-        # @return [nil]
-        #   otherwise
         def subject
           node = matched_node_path.last || return
 
@@ -122,9 +94,6 @@ def subject
         end
         memoize :subject
 
-        # Matched node path
-        #
-        # @return [Array<Parser::AST::Node>]
         def matched_node_path
           AST.find_last_path(ast, &method(:match?))
         end
diff --git a/lib/mutant/matcher/method/instance.rb b/lib/mutant/matcher/method/instance.rb
index d646113b1..65c18f8c7 100644
--- a/lib/mutant/matcher/method/instance.rb
+++ b/lib/mutant/matcher/method/instance.rb
@@ -33,11 +33,6 @@ class Evaluator < Evaluator
 
         private
 
-          # Check if node is matched
-          #
-          # @param [Parser::AST::Node] node
-          #
-          # @return [Boolean]
           def match?(node)
             n_def?(node)                           &&
             node.location.line.equal?(source_line) &&
@@ -50,9 +45,6 @@ class Memoized < self
 
           private
 
-            # Source location
-            #
-            # @return [Array{String,Integer}]
             def source_location
               scope
                 .unmemoized_instance_method(method_name)
diff --git a/lib/mutant/matcher/method/singleton.rb b/lib/mutant/matcher/method/singleton.rb
index 5bcf2a206..4b1515014 100644
--- a/lib/mutant/matcher/method/singleton.rb
+++ b/lib/mutant/matcher/method/singleton.rb
@@ -25,20 +25,10 @@ class Evaluator < Evaluator
 
         private
 
-          # Test for node match
-          #
-          # @param [Parser::AST::Node] node
-          #
-          # @return [Boolean]
           def match?(node)
             n_defs?(node) && line?(node) && name?(node) && receiver?(node)
           end
 
-          # Test for line match
-          #
-          # @param [Parser::AST::Node] node
-          #
-          # @return [Boolean]
           def line?(node)
             node
               .location
@@ -46,20 +36,10 @@ def line?(node)
               .equal?(source_line)
           end
 
-          # Test for name match
-          #
-          # @param [Parser::AST::Node] node
-          #
-          # @return [Boolean]
           def name?(node)
             node.children.fetch(NAME_INDEX).equal?(method_name)
           end
 
-          # Test for receiver match
-          #
-          # @param [Parser::AST::Node] node
-          #
-          # @return [Boolean]
           def receiver?(node)
             receiver = node.children.fetch(RECEIVER_INDEX)
             case receiver.type
@@ -73,11 +53,6 @@ def receiver?(node)
             end
           end
 
-          # Test if receiver name matches context
-          #
-          # @param [Parser::AST::Node] node
-          #
-          # @return [Boolean]
           def receiver_name?(node)
             name = node.children.fetch(NAME_INDEX)
             name.to_s.eql?(context.unqualified_name)
diff --git a/lib/mutant/matcher/methods.rb b/lib/mutant/matcher/methods.rb
index d18239b3a..1a4636853 100644
--- a/lib/mutant/matcher/methods.rb
+++ b/lib/mutant/matcher/methods.rb
@@ -27,16 +27,10 @@ def call(env)
 
     private
 
-      # method matcher class
-      #
-      # @return [Class:Matcher::Method]
       def matcher
         self.class::MATCHER
       end
 
-      # Available methods scope
-      #
-      # @return [Enumerable<Method, UnboundMethod>]
       def methods
         candidate_names.each_with_object([]) do |name, methods|
           method = access(name)
@@ -45,9 +39,6 @@ def methods
       end
       memoize :methods
 
-      # Candidate method names on target scope
-      #
-      # @return [Enumerable<Symbol>]
       def candidate_names
         CANDIDATE_NAMES
           .map(&candidate_scope.method(:public_send))
@@ -55,10 +46,8 @@ def candidate_names
           .sort
       end
 
-      # Candidate scope
-      #
-      # @return [Class, Module]
       abstract_method :candidate_scope
+      private :candidate_scope
 
       # Matcher for singleton methods
       class Singleton < self
@@ -66,18 +55,10 @@ class Singleton < self
 
       private
 
-        # Method object on scope
-        #
-        # @param [Symbol] method_name
-        #
-        # @return [Method]
         def access(method_name)
           scope.method(method_name)
         end
 
-        # Candidate scope
-        #
-        # @return [Class]
         def candidate_scope
           scope.singleton_class
         end
@@ -91,18 +72,10 @@ class Instance < self
 
       private
 
-        # Method object on scope
-        #
-        # @param [Symbol] method_name
-        #
-        # @return [UnboundMethod]
         def access(method_name)
           scope.instance_method(method_name)
         end
 
-        # Candidate scope
-        #
-        # @return [Class, Module]
         def candidate_scope
           scope
         end
diff --git a/lib/mutant/matcher/namespace.rb b/lib/mutant/matcher/namespace.rb
index 513b90546..347e3dba0 100644
--- a/lib/mutant/matcher/namespace.rb
+++ b/lib/mutant/matcher/namespace.rb
@@ -19,22 +19,12 @@ def call(env)
 
     private
 
-      # The matched scopes
-      #
-      # @param [Env] env
-      #
-      # @return [Enumerable<Scope>]
       def matched_scopes(env)
         env
           .matchable_scopes
           .select(&method(:match?))
       end
 
-      # Test scope if matches expression
-      #
-      # @param [Scope] scope
-      #
-      # @return [Boolean]
       def match?(scope)
         expression.prefix?(scope.expression)
       end
diff --git a/lib/mutant/matcher/scope.rb b/lib/mutant/matcher/scope.rb
index b981dff78..e509da5f4 100644
--- a/lib/mutant/matcher/scope.rb
+++ b/lib/mutant/matcher/scope.rb
@@ -29,9 +29,6 @@ def call(env)
 
     private
 
-      # Effective matchers
-      #
-      # @return [Enumerable<Matcher>]
       def effective_matchers
         MATCHERS.map { |matcher| matcher.new(scope) }
       end
diff --git a/lib/mutant/meta/example/dsl.rb b/lib/mutant/meta/example/dsl.rb
index ed3b93b22..8897d7697 100644
--- a/lib/mutant/meta/example/dsl.rb
+++ b/lib/mutant/meta/example/dsl.rb
@@ -49,21 +49,11 @@ def example
 
       private
 
-        # Set original source
-        #
-        # @param [String,Parser::AST::Node] input
-        #
-        # @return [undefined]
         def source(input)
           fail 'source already defined' if @node
           @node = node(input)
         end
 
-        # Add expected mutation
-        #
-        # @param [String,Parser::AST::Node] input
-        #
-        # @return [undefined]
         def mutation(input)
           node = node(input)
           if @expected.include?(node)
@@ -72,22 +62,11 @@ def mutation(input)
           @expected << node
         end
 
-        # Add singleton mutations
-        #
-        # @return [undefined]
         def singleton_mutations
           mutation('nil')
           mutation('self')
         end
 
-        # Helper method to coerce input to node
-        #
-        # @param [String,Parser::AST::Node] input
-        #
-        # @return [Parser::AST::Node]
-        #
-        # @raise [RuntimeError]
-        #   in case input cannot be coerced
         def node(input)
           case input
           when String
diff --git a/lib/mutant/meta/example/verification.rb b/lib/mutant/meta/example/verification.rb
index b2d1db8d3..621aaf62a 100644
--- a/lib/mutant/meta/example/verification.rb
+++ b/lib/mutant/meta/example/verification.rb
@@ -35,9 +35,6 @@ def error_report
 
       private
 
-        # Unexpected mutations
-        #
-        # @return [Array<Mutation>]
         def unexpected
           mutations.reject do |mutation|
             example.expected.include?(mutation.node)
@@ -45,9 +42,6 @@ def unexpected
         end
         memoize :unexpected
 
-        # Missing mutations
-        #
-        # @return [Array<Mutation>]
         def missing
           (example.expected - mutations.map(&:node)).map do |node|
             Mutation::Evil.new(self, node)
@@ -55,9 +49,6 @@ def missing
         end
         memoize :missing
 
-        # Mutations that generated invalid syntax
-        #
-        # @return [Enumerable<Mutation>]
         def invalid_syntax
           mutations.reject do |mutation|
             ::Parser::CurrentRuby.parse(mutation.source)
@@ -66,19 +57,11 @@ def invalid_syntax
         end
         memoize :invalid_syntax
 
-        # Mutations with no diff to original
-        #
-        # @return [Enumerable<Mutation>]
         def no_diffs
           mutations.select { |mutation| mutation.source.eql?(example.source) }
         end
         memoize :no_diffs
 
-        # Mutation report
-        #
-        # @param [Array<Mutation>] mutations
-        #
-        # @return [Array<Hash>]
         def format_mutations(mutations)
           mutations.map do |mutation|
             {
@@ -88,9 +71,6 @@ def format_mutations(mutations)
           end
         end
 
-        # No diff mutation report
-        #
-        # @return [Array, nil]
         def no_diff_report
           no_diffs.map do |mutation|
             {
diff --git a/lib/mutant/minitest/coverage.rb b/lib/mutant/minitest/coverage.rb
index 2ff8cf9bf..7acec17b4 100644
--- a/lib/mutant/minitest/coverage.rb
+++ b/lib/mutant/minitest/coverage.rb
@@ -40,11 +40,6 @@ def resolve_cover_expression
 
     private
 
-      # Attempt to resolve superclass cover expressio
-      #
-      # @return [String, nil]
-      #
-      # @api private
       def try_superclass_cover_expression
         return if superclass.equal?(::Minitest::Runnable)
 
diff --git a/lib/mutant/mutation.rb b/lib/mutant/mutation.rb
index 615419151..df185920c 100644
--- a/lib/mutant/mutation.rb
+++ b/lib/mutant/mutation.rb
@@ -74,9 +74,6 @@ def insert(kernel)
 
   private
 
-    # SHA1 sum of source and subject identification
-    #
-    # @return [String]
     def sha1
       Digest::SHA1.hexdigest(subject.identification + CODE_DELIMITER + source)
     end
diff --git a/lib/mutant/mutator.rb b/lib/mutant/mutator.rb
index 645f57186..a03f33df7 100644
--- a/lib/mutant/mutator.rb
+++ b/lib/mutant/mutator.rb
@@ -18,9 +18,6 @@ def self.mutate(node, parent = nil)
       self::REGISTRY.lookup(node.type).call(node, parent)
     end
 
-    # Register node class handler
-    #
-    # @return [undefined]
     def self.handle(*types)
       types.each do |type|
         self::REGISTRY.register(type, self)
@@ -35,13 +32,6 @@ def self.handle(*types)
 
   private
 
-    # Initialize object
-    #
-    # @param [Object] input
-    # @param [Object] parent
-    # @param [#call(node)] block
-    #
-    # @return [undefined]
     def initialize(_input, _parent = nil)
       super
 
@@ -50,41 +40,23 @@ def initialize(_input, _parent = nil)
       dispatch
     end
 
-    # Test if generated object is not guarded from emitting
-    #
-    # @param [Object] object
-    #
-    # @return [Boolean]
     def new?(object)
       !object.eql?(input)
     end
 
-    # Dispatch node generations
-    #
-    # @return [undefined]
     abstract_method :dispatch
+    private :dispatch
 
-    # Emit generated mutation if object is not equivalent to input
-    #
-    # @param [Object] object
-    #
-    # @return [undefined]
     def emit(object)
       return unless new?(object)
 
       output << object
     end
 
-    # Run input with mutator
-    #
-    # @return [undefined]
     def run(mutator)
       mutator.call(input).each(&method(:emit))
     end
 
-    # Shortcut to create a new unfrozen duplicate of input
-    #
-    # @return [Object]
     def dup_input
       input.dup
     end
diff --git a/lib/mutant/mutator/node.rb b/lib/mutant/mutator/node.rb
index d20784658..57131f7f2 100644
--- a/lib/mutant/mutator/node.rb
+++ b/lib/mutant/mutator/node.rb
@@ -34,21 +34,9 @@ def self.define_named_child(name, index)
 
     private
 
-      # Node to mutate
-      #
-      # @return [Parser::AST::Node]
-      alias_method :node, :input
-
-      # Duplicate of original
-      #
-      # @return [Parser::AST::Node]
+      alias_method :node,     :input
       alias_method :dup_node, :dup_input
 
-      # Dispatch on child index
-      #
-      # @param [Integer] index
-      #
-      # @return [undefined]
       def mutate_child(index, &block)
         block ||= TAUTOLOGY
         Mutator.mutate(children.fetch(index), self).each do |mutation|
@@ -57,108 +45,55 @@ def mutate_child(index, &block)
         end
       end
 
-      # Emit delete child mutation
-      #
-      # @param [Integer] index
-      #
-      # @return [undefined]
       def delete_child(index)
         dup_children = children.dup
         dup_children.delete_at(index)
         emit_type(*dup_children)
       end
 
-      # Emit updated child
-      #
-      # @param [Integer] index
-      # @param [Parser::AST::Node] node
-      #
-      # @return [undefined]
       def emit_child_update(index, node)
         new_children = children.dup
         new_children[index] = node
         emit_type(*new_children)
       end
 
-      # Emit a new AST node with same class as wrapped node
-      #
-      # @param [Array<Parser::AST::Node>] children
-      #
-      # @return [undefined]
       def emit_type(*children)
         emit(::Parser::AST::Node.new(node.type, children))
       end
 
-      # Emit propagation if node can stand alone
-      #
-      # @return [undefined]
       def emit_propagation(node)
         emit(node) unless AST::Types::NOT_STANDALONE.include?(node.type)
       end
 
-      # Emit singleton literals
-      #
-      # @return [undefined]
       def emit_singletons
         emit_nil
         emit_self
       end
 
-      # Emit a literal self
-      #
-      # @return [undefined]
       def emit_self
         emit(N_SELF)
       end
 
-      # Emit a literal nil
-      #
-      # @return [undefined]
       def emit_nil
         emit(N_NIL) unless left_assignment?
       end
 
-      # Parent node
-      #
-      # @return [Parser::AST::Node] node
-      #   if parent with node is present
-      #
-      # @return [nil]
-      #   otherwise
       def parent_node
         parent&.node
       end
 
-      # Parent type
-      #
-      # @return [Symbol] type
-      #   if parent with type is present
-      #
-      # @return [nil]
-      #   otherwise
       def parent_type
         parent_node&.type
       end
 
-      # Test if the node is the left of an or_asgn or op_asgn
-      #
-      # @return [Boolean]
       def left_assignment?
         AST::Types::OP_ASSIGN.include?(parent_type) && parent.node.children.first.equal?(node)
       end
 
-      # Children indices
-      #
-      # @param [Range] range
-      #
-      # @return [Enumerable<Integer>]
       def children_indices(range)
         range.begin.upto(children.length + range.end)
       end
 
-      # Emit single child mutation
-      #
-      # @return [undefined]
       def mutate_single_child
         children.each_with_index do |child, index|
           mutate_child(index)
diff --git a/lib/mutant/mutator/node/and_asgn.rb b/lib/mutant/mutator/node/and_asgn.rb
index dffd247e7..08d149d99 100644
--- a/lib/mutant/mutator/node/and_asgn.rb
+++ b/lib/mutant/mutator/node/and_asgn.rb
@@ -13,9 +13,6 @@ class AndAsgn < self
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           emit_singletons
           emit_left_mutations do |node|
diff --git a/lib/mutant/mutator/node/argument.rb b/lib/mutant/mutator/node/argument.rb
index 52f0db757..cb10f35c7 100644
--- a/lib/mutant/mutator/node/argument.rb
+++ b/lib/mutant/mutator/node/argument.rb
@@ -14,24 +14,15 @@ class Argument < self
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           emit_name_mutation
         end
 
-        # Emit name mutations
-        #
-        # @return [undefined]
         def emit_name_mutation
           return if skip?
           emit_name(:"#{UNDERSCORE}#{name}")
         end
 
-        # Test if argument mutation is skipped
-        #
-        # @return [Boolean]
         def skip?
           name.to_s.start_with?(UNDERSCORE)
         end
@@ -50,18 +41,12 @@ class Optional < self
 
         private
 
-          # Emit mutations
-          #
-          # @return [undefined]
           def dispatch
             emit_name_mutation
             emit_required_mutation
             emit_default_mutations
           end
 
-          # Emit required mutation
-          #
-          # @return [undefined]
           def emit_required_mutation
             emit(s(TYPE_MAP.fetch(node.type), name))
           end
diff --git a/lib/mutant/mutator/node/arguments.rb b/lib/mutant/mutator/node/arguments.rb
index 8830e5c53..6f6505619 100644
--- a/lib/mutant/mutator/node/arguments.rb
+++ b/lib/mutant/mutator/node/arguments.rb
@@ -12,18 +12,12 @@ class Arguments < self
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           emit_argument_presence
           emit_argument_mutations
           emit_mlhs_expansion
         end
 
-        # Emit argument presence mutation
-        #
-        # @return [undefined]
         def emit_argument_presence
           emit_type
 
@@ -34,9 +28,6 @@ def emit_argument_presence
           end
         end
 
-        # Emit argument mutations
-        #
-        # @return [undefined]
         def emit_argument_mutations
           children.each_with_index do |child, index|
             Mutator.mutate(child).each do |mutant|
@@ -46,18 +37,10 @@ def emit_argument_mutations
           end
         end
 
-        # Test if child mutation is allowed
-        #
-        # @param [Parser::AST::Node]
-        #
-        # @return [Boolean]
         def invalid_argument_replacement?(mutant, index)
           n_arg?(mutant) && children[0...index].any?(&method(:n_optarg?))
         end
 
-        # Emit mlhs expansions
-        #
-        # @return [undefined]
         def emit_mlhs_expansion
           mlhs_childs_with_index.each do |child, index|
             dup_children = children.dup
@@ -67,9 +50,6 @@ def emit_mlhs_expansion
           end
         end
 
-        # Multiple left hand side childs
-        #
-        # @return [Enumerable<Parser::AST::Node, Integer>]
         def mlhs_childs_with_index
           children.each_with_index.select do |child,|
             n_mlhs?(child)
diff --git a/lib/mutant/mutator/node/begin.rb b/lib/mutant/mutator/node/begin.rb
index 666465e48..70c447c60 100644
--- a/lib/mutant/mutator/node/begin.rb
+++ b/lib/mutant/mutator/node/begin.rb
@@ -11,9 +11,6 @@ class Begin < self
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           mutate_single_child do |child|
             emit(child)
diff --git a/lib/mutant/mutator/node/binary.rb b/lib/mutant/mutator/node/binary.rb
index ea7c57ce1..3e2492bbf 100644
--- a/lib/mutant/mutator/node/binary.rb
+++ b/lib/mutant/mutator/node/binary.rb
@@ -17,9 +17,6 @@ class Binary < self
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           emit_singletons
           emit_promotions
@@ -29,35 +26,15 @@ def dispatch
           emit_right_mutations
         end
 
-        # Emit operator mutations
-        #
-        # @return [undefined]
         def emit_operator_mutations
           emit(s(INVERSE.fetch(node.type), left, right))
         end
 
-        # Emit promotions
-        #
-        # @return [undefined]
         def emit_promotions
           emit(left)
           emit(right)
         end
 
-        # Emit left negation
-        #
-        # We do not emit right negation as the `and` and `or` nodes
-        # in ruby are also used for control flow.
-        #
-        # Irrespective of their syntax, aka `||` parses internally to `or`.
-        #
-        # `do_a or do_b`. Negating left makes sense, negating right
-        # only when the result is actually used.
-        #
-        # It *would* be possible to emit the right negation in case the use of the result is proved.
-        # Like parent is an assignment to an {l,i}var. Dunno if we ever get the time to do that.
-        #
-        # @return [undefined]
         def emit_left_negation
           emit(s(node.type, n_not(left), right))
         end
diff --git a/lib/mutant/mutator/node/block.rb b/lib/mutant/mutator/node/block.rb
index b9cb3bc93..745f7b42c 100644
--- a/lib/mutant/mutator/node/block.rb
+++ b/lib/mutant/mutator/node/block.rb
@@ -11,9 +11,6 @@ class Block < self
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           emit_singletons
           emit(send) unless n_lambda?(send)
@@ -23,9 +20,6 @@ def dispatch
           mutate_body
         end
 
-        # Emit body mutations
-        #
-        # @return [undefined]
         def mutate_body
           emit_body(nil)
           emit_body(N_RAISE)
@@ -37,18 +31,12 @@ def mutate_body
           mutate_body_receiver
         end
 
-        # Test if body has control structures
-        #
-        # @return [Boolean]
         def body_has_control?
           AST.find_last_path(body) do |node|
             n_break?(node) || n_next?(node)
           end.any?
         end
 
-        # Mutate method send in body scope of `send`
-        #
-        # @return [undefined]
         def mutate_body_receiver
           return if n_lambda?(send) || !n_send?(body)
 
@@ -57,9 +45,6 @@ def mutate_body_receiver
           emit(s(:send, send, body_meta.selector, *body_meta.arguments))
         end
 
-        # Test for valid send mutations
-        #
-        # @return [true, false, nil]
         def valid_send_mutation?(node)
           return unless n_send?(node)
 
diff --git a/lib/mutant/mutator/node/break.rb b/lib/mutant/mutator/node/break.rb
index f942f76af..8e5c38e32 100644
--- a/lib/mutant/mutator/node/break.rb
+++ b/lib/mutant/mutator/node/break.rb
@@ -11,9 +11,6 @@ class Break < Generic
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           super()
           emit_singletons
diff --git a/lib/mutant/mutator/node/case.rb b/lib/mutant/mutator/node/case.rb
index 131bcff95..f181c6b33 100644
--- a/lib/mutant/mutator/node/case.rb
+++ b/lib/mutant/mutator/node/case.rb
@@ -13,9 +13,6 @@ class Case < self
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           emit_singletons
           emit_condition_mutations if condition
@@ -23,9 +20,6 @@ def dispatch
           emit_else_mutations
         end
 
-        # Emit when mutations
-        #
-        # @return [undefined]
         def emit_when_mutations
           indices = children.each_index.drop(1).take(children.length - 2)
           one = indices.one?
@@ -35,9 +29,6 @@ def emit_when_mutations
           end
         end
 
-        # Emit else mutations
-        #
-        # @return [undefined]
         def emit_else_mutations
           else_branch = children.last
           else_index = children.length - 1
diff --git a/lib/mutant/mutator/node/class.rb b/lib/mutant/mutator/node/class.rb
index 60a55f93f..11fcf0300 100644
--- a/lib/mutant/mutator/node/class.rb
+++ b/lib/mutant/mutator/node/class.rb
@@ -11,9 +11,6 @@ class Class < self
 
       private
 
-        # Emit mutations only for class body
-        #
-        # @return [undefined]
         def dispatch
           emit_body_mutations if body
         end
diff --git a/lib/mutant/mutator/node/conditional_loop.rb b/lib/mutant/mutator/node/conditional_loop.rb
index 68503ea12..23ecd74fd 100644
--- a/lib/mutant/mutator/node/conditional_loop.rb
+++ b/lib/mutant/mutator/node/conditional_loop.rb
@@ -13,9 +13,6 @@ class ConditionalLoop < self
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           emit_singletons
           emit_condition_mutations
diff --git a/lib/mutant/mutator/node/const.rb b/lib/mutant/mutator/node/const.rb
index 598f494a0..79ed266ca 100644
--- a/lib/mutant/mutator/node/const.rb
+++ b/lib/mutant/mutator/node/const.rb
@@ -11,9 +11,6 @@ class Const < self
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           emit_singletons unless parent_node && n_const?(parent_node)
           emit_type(nil, *children.drop(1))
diff --git a/lib/mutant/mutator/node/define.rb b/lib/mutant/mutator/node/define.rb
index 214a85575..cd09db1ec 100644
--- a/lib/mutant/mutator/node/define.rb
+++ b/lib/mutant/mutator/node/define.rb
@@ -8,9 +8,6 @@ class Define < self
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           emit_arguments_mutations
           emit_optarg_body_assignments
@@ -20,9 +17,6 @@ def dispatch
           emit_body_mutations if body
         end
 
-        # Emit mutations with optional arguments as assignments in method
-        #
-        # @return [undefined]
         def emit_optarg_body_assignments
           arguments.children.each do |argument|
             next unless n_optarg?(argument) && AST::Meta::Optarg.new(argument).used?
@@ -31,11 +25,6 @@ def emit_optarg_body_assignments
           end
         end
 
-        # Emit valid body ASTs depending on instance body
-        #
-        # @param node [Parser::AST::Node]
-        #
-        # @return [undefined]
         def emit_body_prepend(node)
           if body
             emit_body(s(:begin, node, body))
diff --git a/lib/mutant/mutator/node/defined.rb b/lib/mutant/mutator/node/defined.rb
index bd8c162f8..96898852c 100644
--- a/lib/mutant/mutator/node/defined.rb
+++ b/lib/mutant/mutator/node/defined.rb
@@ -12,9 +12,6 @@ class Defined < self
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           emit_singletons
           emit(N_TRUE)
diff --git a/lib/mutant/mutator/node/dstr.rb b/lib/mutant/mutator/node/dstr.rb
index 0bf262e50..48e2a39f9 100644
--- a/lib/mutant/mutator/node/dstr.rb
+++ b/lib/mutant/mutator/node/dstr.rb
@@ -11,9 +11,6 @@ class Dstr < Generic
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           super()
           emit_singletons
diff --git a/lib/mutant/mutator/node/dsym.rb b/lib/mutant/mutator/node/dsym.rb
index 15d3f7b63..015a572af 100644
--- a/lib/mutant/mutator/node/dsym.rb
+++ b/lib/mutant/mutator/node/dsym.rb
@@ -11,9 +11,6 @@ class Dsym < Generic
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           super()
           emit_singletons
diff --git a/lib/mutant/mutator/node/generic.rb b/lib/mutant/mutator/node/generic.rb
index ac13ae246..2d215ce30 100644
--- a/lib/mutant/mutator/node/generic.rb
+++ b/lib/mutant/mutator/node/generic.rb
@@ -8,9 +8,6 @@ class Generic < self
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           children.each_with_index do |child, index|
             mutate_child(index) if child.instance_of?(::Parser::AST::Node)
diff --git a/lib/mutant/mutator/node/if.rb b/lib/mutant/mutator/node/if.rb
index 845b81484..bc17454d4 100644
--- a/lib/mutant/mutator/node/if.rb
+++ b/lib/mutant/mutator/node/if.rb
@@ -12,9 +12,6 @@ class If < self
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           emit_singletons
           mutate_condition
@@ -22,9 +19,6 @@ def dispatch
           mutate_else_branch
         end
 
-        # Emit condition mutations
-        #
-        # @return [undefined]
         def mutate_condition
           emit_condition_mutations do |node|
             !n_self?(node)
@@ -34,9 +28,6 @@ def mutate_condition
           emit_type(N_FALSE, if_branch, else_branch)
         end
 
-        # Emit if branch mutations
-        #
-        # @return [undefined]
         def mutate_if_branch
           emit_type(condition, else_branch, nil) if else_branch
           return unless if_branch
@@ -45,9 +36,6 @@ def mutate_if_branch
           emit_type(condition, if_branch, nil)
         end
 
-        # Emit else branch mutations
-        #
-        # @return [undefined]
         def mutate_else_branch
           return unless else_branch
           emit(else_branch)
diff --git a/lib/mutant/mutator/node/index.rb b/lib/mutant/mutator/node/index.rb
index dbd1fbefb..2063fb242 100644
--- a/lib/mutant/mutator/node/index.rb
+++ b/lib/mutant/mutator/node/index.rb
@@ -14,9 +14,6 @@ class Index < self
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           emit_singletons
           emit_receiver_mutations { |node| !n_nil?(node) }
@@ -26,9 +23,6 @@ def dispatch
           mutate_indices
         end
 
-        # Emit send forms
-        #
-        # @return [undefined]
         def emit_send_forms
           return if left_assignment?
 
@@ -37,9 +31,6 @@ def emit_send_forms
           end
         end
 
-        # Emit mutation `foo[n..-1]` -> `foo.drop(n)`
-        #
-        # @return [undefined]
         def emit_drop_mutation
           return unless indices.one? && n_irange?(Mutant::Util.one(indices))
 
@@ -50,9 +41,6 @@ def emit_drop_mutation
           emit(s(:send, receiver, :drop, start))
         end
 
-        # Mutate indices
-        #
-        # @return [undefined]
         def mutate_indices
           children_indices(index_range).each do |index|
             emit_propagation(children.fetch(index)) unless left_assignment?
@@ -61,9 +49,6 @@ def mutate_indices
           end
         end
 
-        # The index nodes
-        #
-        # @return [Enumerable<Parser::AST::Node>]
         def indices
           children[index_range]
         end
@@ -74,9 +59,6 @@ class Read < self
 
         private
 
-          # The range index children can be found
-          #
-          # @return [Range]
           def index_range
             NO_VALUE_RANGE
           end
@@ -92,9 +74,6 @@ class Assign < self
 
         private
 
-          # Emit mutations
-          #
-          # @return [undefined]
           def dispatch
             super()
 
@@ -105,16 +84,10 @@ def dispatch
             mutate_child(children.length.pred)
           end
 
-          # Emit index read
-          #
-          # @return [undefined]
           def emit_index_read
             emit(s(:index, receiver, *children[index_range]))
           end
 
-          # Index indices
-          #
-          # @return [Range<Integer>]
           def index_range
             if left_assignment?
               NO_VALUE_RANGE
diff --git a/lib/mutant/mutator/node/kwbegin.rb b/lib/mutant/mutator/node/kwbegin.rb
index 1576b837c..2b83f0dd5 100644
--- a/lib/mutant/mutator/node/kwbegin.rb
+++ b/lib/mutant/mutator/node/kwbegin.rb
@@ -11,9 +11,6 @@ class Kwbegin < Generic
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           super()
           emit_singletons
diff --git a/lib/mutant/mutator/node/literal.rb b/lib/mutant/mutator/node/literal.rb
index 63eb0aa52..2ae68498a 100644
--- a/lib/mutant/mutator/node/literal.rb
+++ b/lib/mutant/mutator/node/literal.rb
@@ -9,9 +9,6 @@ class Literal < self
 
       private
 
-        # Emit values
-        #
-        # @return [undefined]
         def emit_values
           values.each(&method(:emit_type))
         end
diff --git a/lib/mutant/mutator/node/literal/array.rb b/lib/mutant/mutator/node/literal/array.rb
index 18dcb391b..34797db2b 100644
--- a/lib/mutant/mutator/node/literal/array.rb
+++ b/lib/mutant/mutator/node/literal/array.rb
@@ -13,9 +13,6 @@ class Array < self
 
         private
 
-          # Emit mutations
-          #
-          # @return [undefined]
           def dispatch
             emit_singletons
             emit_type
@@ -24,9 +21,6 @@ def dispatch
             emit(first) unless n_splat?(first)
           end
 
-          # Mutate body
-          #
-          # @return [undefined]
           def mutate_body
             children.each_index do |index|
               dup_children = children.dup
diff --git a/lib/mutant/mutator/node/literal/boolean.rb b/lib/mutant/mutator/node/literal/boolean.rb
index ab40fa820..8867862d2 100644
--- a/lib/mutant/mutator/node/literal/boolean.rb
+++ b/lib/mutant/mutator/node/literal/boolean.rb
@@ -16,9 +16,6 @@ class Boolean < self
 
           handle(*MAP.keys)
 
-          # Emit mutations
-          #
-          # @return [undefined]
           def dispatch
             emit(s(MAP.fetch(node.type)))
           end
diff --git a/lib/mutant/mutator/node/literal/float.rb b/lib/mutant/mutator/node/literal/float.rb
index 7786a4d46..7332200b1 100644
--- a/lib/mutant/mutator/node/literal/float.rb
+++ b/lib/mutant/mutator/node/literal/float.rb
@@ -11,9 +11,6 @@ class Float < self
 
         private
 
-          # Emit mutations
-          #
-          # @return [undefined]
           def dispatch
             emit_singletons
             emit_values
@@ -26,16 +23,10 @@ def dispatch
             N_INFINITY
           ].freeze
 
-          # Emit special cases
-          #
-          # @return [undefined]
           def emit_special_cases
             SPECIAL.each(&method(:emit))
           end
 
-          # Values to mutate to
-          #
-          # @return [Array]
           def values
             original = children.first
 
diff --git a/lib/mutant/mutator/node/literal/hash.rb b/lib/mutant/mutator/node/literal/hash.rb
index 95576adbc..5bdefc219 100644
--- a/lib/mutant/mutator/node/literal/hash.rb
+++ b/lib/mutant/mutator/node/literal/hash.rb
@@ -11,18 +11,12 @@ class Hash < self
 
         private
 
-          # Emit mutations
-          #
-          # @return [undefined]
           def dispatch
             emit_singletons
             emit_type
             mutate_body
           end
 
-          # Mutate body
-          #
-          # @return [undefined]
           def mutate_body
             children.each_index do |index|
               mutate_child(index)
@@ -41,9 +35,6 @@ class Pair < Node
 
           private
 
-            # Emit mutations
-            #
-            # @return [undefined]
             def dispatch
               emit_key_mutations
               emit_value_mutations
diff --git a/lib/mutant/mutator/node/literal/integer.rb b/lib/mutant/mutator/node/literal/integer.rb
index 5a4ffbf99..b3e4f25ab 100644
--- a/lib/mutant/mutator/node/literal/integer.rb
+++ b/lib/mutant/mutator/node/literal/integer.rb
@@ -11,24 +11,15 @@ class Integer < self
 
         private
 
-          # Emit mutations
-          #
-          # @return [undefined]
           def dispatch
             emit_singletons
             emit_values
           end
 
-          # Values to mutate to
-          #
-          # @return [Array]
           def values
             [0, 1, -value, value + 1, value - 1]
           end
 
-          # Literal original value
-          #
-          # @return [Object]
           def value
             value, = children
             value
diff --git a/lib/mutant/mutator/node/literal/nil.rb b/lib/mutant/mutator/node/literal/nil.rb
index d238573b4..88f3153be 100644
--- a/lib/mutant/mutator/node/literal/nil.rb
+++ b/lib/mutant/mutator/node/literal/nil.rb
@@ -11,9 +11,6 @@ class Nil < self
 
         private
 
-          # Emit mutations
-          #
-          # @return [undefined]
           def dispatch; end
 
         end # Nil
diff --git a/lib/mutant/mutator/node/literal/range.rb b/lib/mutant/mutator/node/literal/range.rb
index 8665b50b3..2346610ca 100644
--- a/lib/mutant/mutator/node/literal/range.rb
+++ b/lib/mutant/mutator/node/literal/range.rb
@@ -19,9 +19,6 @@ class Range < self
 
         private
 
-          # Emit mutations
-          #
-          # @return [undefined]
           def dispatch
             emit_singletons
             emit_inverse
@@ -29,9 +26,6 @@ def dispatch
             emit_upper_bound_mutations
           end
 
-          # Inverse node
-          #
-          # @return [Parser::AST::Node]
           def emit_inverse
             emit(s(MAP.fetch(node.type), *children))
           end
diff --git a/lib/mutant/mutator/node/literal/regex.rb b/lib/mutant/mutator/node/literal/regex.rb
index 47ae6805b..b208b0253 100644
--- a/lib/mutant/mutator/node/literal/regex.rb
+++ b/lib/mutant/mutator/node/literal/regex.rb
@@ -14,16 +14,10 @@ class Regex < self
 
         private
 
-          # Original regexp options
-          #
-          # @return [Parser::AST::Node]
           def options
             children.last
           end
 
-          # Emit mutations
-          #
-          # @return [undefined]
           def dispatch
             emit_singletons unless parent_node
             children.each_with_index do |child, index|
diff --git a/lib/mutant/mutator/node/literal/string.rb b/lib/mutant/mutator/node/literal/string.rb
index 473f20e38..7d7755fda 100644
--- a/lib/mutant/mutator/node/literal/string.rb
+++ b/lib/mutant/mutator/node/literal/string.rb
@@ -11,9 +11,6 @@ class String < self
 
         private
 
-          # Emit mutations
-          #
-          # @return [undefined]
           def dispatch
             emit_singletons
           end
diff --git a/lib/mutant/mutator/node/literal/symbol.rb b/lib/mutant/mutator/node/literal/symbol.rb
index c0881566e..7dae92871 100644
--- a/lib/mutant/mutator/node/literal/symbol.rb
+++ b/lib/mutant/mutator/node/literal/symbol.rb
@@ -15,9 +15,6 @@ class Symbol < self
 
         private
 
-          # Emit mutations
-          #
-          # @return [undefined]
           def dispatch
             emit_singletons
             Util::Symbol.call(value).each(&method(:emit_type))
diff --git a/lib/mutant/mutator/node/masgn.rb b/lib/mutant/mutator/node/masgn.rb
index 8ac5c3d13..28156cf7f 100644
--- a/lib/mutant/mutator/node/masgn.rb
+++ b/lib/mutant/mutator/node/masgn.rb
@@ -13,9 +13,6 @@ class MultipleAssignment < self
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           emit_singletons
         end
diff --git a/lib/mutant/mutator/node/match_current_line.rb b/lib/mutant/mutator/node/match_current_line.rb
index 759b38045..3a7001719 100644
--- a/lib/mutant/mutator/node/match_current_line.rb
+++ b/lib/mutant/mutator/node/match_current_line.rb
@@ -12,9 +12,6 @@ class MatchCurrentLine < self
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           emit_singletons
           emit_regexp_mutations
diff --git a/lib/mutant/mutator/node/mlhs.rb b/lib/mutant/mutator/node/mlhs.rb
index 02632ec18..e7de36270 100644
--- a/lib/mutant/mutator/node/mlhs.rb
+++ b/lib/mutant/mutator/node/mlhs.rb
@@ -10,9 +10,6 @@ class MLHS < self
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           mutate_single_child do |_child, index|
             delete_child(index)
diff --git a/lib/mutant/mutator/node/named_value/access.rb b/lib/mutant/mutator/node/named_value/access.rb
index 67ef182e6..a6d07cbeb 100644
--- a/lib/mutant/mutator/node/named_value/access.rb
+++ b/lib/mutant/mutator/node/named_value/access.rb
@@ -12,9 +12,6 @@ class Access < Node
 
         private
 
-          # Emit mutations
-          #
-          # @return [undefined]
           def dispatch
             emit_singletons
           end
@@ -27,26 +24,17 @@ class Ivar < Access
 
             children :name
 
-            # Emit mutations
-            #
-            # @return [undefined]
+          private
+
             def dispatch
               emit_attribute_read
               super()
             end
 
-          private
-
-            # Emit instance variable as attribute send
-            #
-            # @return [undefined]
             def emit_attribute_read
               emit(s(:send, nil, attribute_name))
             end
 
-            # Variable name without leading '@'
-            #
-            # @return [Symbol]
             def attribute_name
               name.slice(NAME_RANGE).to_sym
             end
diff --git a/lib/mutant/mutator/node/named_value/constant_assignment.rb b/lib/mutant/mutator/node/named_value/constant_assignment.rb
index 35745e743..a31a832a3 100644
--- a/lib/mutant/mutator/node/named_value/constant_assignment.rb
+++ b/lib/mutant/mutator/node/named_value/constant_assignment.rb
@@ -14,9 +14,6 @@ class ConstantAssignment < Node
 
         private
 
-          # Emit mutations
-          #
-          # @return [undefined]
           def dispatch
             mutate_name
             return unless value # op asgn
@@ -24,16 +21,10 @@ def dispatch
             emit_remove_const
           end
 
-          # Emit remove_const
-          #
-          # @return [undefined]
           def emit_remove_const
             emit(s(:send, cbase, :remove_const, s(:sym, name)))
           end
 
-          # Emit name mutations
-          #
-          # @return [undefined]
           def mutate_name
             Util::Symbol.call(name).each do |name|
               emit_name(name.upcase)
diff --git a/lib/mutant/mutator/node/named_value/variable_assignment.rb b/lib/mutant/mutator/node/named_value/variable_assignment.rb
index 3d10bf6c0..9d3735523 100644
--- a/lib/mutant/mutator/node/named_value/variable_assignment.rb
+++ b/lib/mutant/mutator/node/named_value/variable_assignment.rb
@@ -25,18 +25,12 @@ class VariableAssignment < Node
 
         private
 
-          # Emit mutations
-          #
-          # @return [undefined]
           def dispatch
             emit_singletons
             mutate_name
             emit_value_mutations if value # op asgn!
           end
 
-          # Emit name mutations
-          #
-          # @return [undefined]
           def mutate_name
             prefix, regexp = MAP.fetch(node.type)
             stripped = name.to_s.sub(regexp, EMPTY_STRING)
diff --git a/lib/mutant/mutator/node/next.rb b/lib/mutant/mutator/node/next.rb
index a58c917c1..9397b2543 100644
--- a/lib/mutant/mutator/node/next.rb
+++ b/lib/mutant/mutator/node/next.rb
@@ -11,9 +11,6 @@ class Next < Generic
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           super()
           emit_singletons
diff --git a/lib/mutant/mutator/node/noop.rb b/lib/mutant/mutator/node/noop.rb
index 078d85bd6..a56b8a0ce 100644
--- a/lib/mutant/mutator/node/noop.rb
+++ b/lib/mutant/mutator/node/noop.rb
@@ -11,9 +11,6 @@ class Noop < self
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           # noop
         end
diff --git a/lib/mutant/mutator/node/nthref.rb b/lib/mutant/mutator/node/nthref.rb
index e1aa3c300..ff4e32f45 100644
--- a/lib/mutant/mutator/node/nthref.rb
+++ b/lib/mutant/mutator/node/nthref.rb
@@ -12,9 +12,6 @@ class NthRef < self
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           unless number.equal?(1)
             emit_number(number - 1)
diff --git a/lib/mutant/mutator/node/op_asgn.rb b/lib/mutant/mutator/node/op_asgn.rb
index b41056939..d6affbdd9 100644
--- a/lib/mutant/mutator/node/op_asgn.rb
+++ b/lib/mutant/mutator/node/op_asgn.rb
@@ -13,9 +13,6 @@ class OpAsgn < self
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           emit_singletons
           emit_left_mutations do |node|
diff --git a/lib/mutant/mutator/node/or_asgn.rb b/lib/mutant/mutator/node/or_asgn.rb
index 1d0aae7d4..d8a4a7d90 100644
--- a/lib/mutant/mutator/node/or_asgn.rb
+++ b/lib/mutant/mutator/node/or_asgn.rb
@@ -13,9 +13,6 @@ class OrAsgn < self
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           emit_singletons
           emit_right_mutations
diff --git a/lib/mutant/mutator/node/procarg_zero.rb b/lib/mutant/mutator/node/procarg_zero.rb
index 30c9af4a1..a634bc853 100644
--- a/lib/mutant/mutator/node/procarg_zero.rb
+++ b/lib/mutant/mutator/node/procarg_zero.rb
@@ -17,9 +17,6 @@ class ProcargZero < self
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           name = Mutant::Util.one(argument.children)
 
diff --git a/lib/mutant/mutator/node/regopt.rb b/lib/mutant/mutator/node/regopt.rb
index f43e3a23d..c95c133d7 100644
--- a/lib/mutant/mutator/node/regopt.rb
+++ b/lib/mutant/mutator/node/regopt.rb
@@ -13,16 +13,10 @@ class Regopt < self
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           emit_type(*mutated_flags)
         end
 
-        # Altered flags array excluding case insensitive flag
-        #
-        # @return [Array<Symbol>]
         def mutated_flags
           (children - MUTATED_FLAGS)
         end
diff --git a/lib/mutant/mutator/node/resbody.rb b/lib/mutant/mutator/node/resbody.rb
index b7b5d1481..ca8b6cb21 100644
--- a/lib/mutant/mutator/node/resbody.rb
+++ b/lib/mutant/mutator/node/resbody.rb
@@ -12,18 +12,12 @@ class Resbody < self
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           emit_assignment(nil)
           emit_body_mutations if body
           mutate_captures
         end
 
-        # Mutate captures
-        #
-        # @return [undefined]
         def mutate_captures
           return unless captures
           Util::Array::Element.call(captures.children).each do |matchers|
diff --git a/lib/mutant/mutator/node/rescue.rb b/lib/mutant/mutator/node/rescue.rb
index 793906061..c9858ed18 100644
--- a/lib/mutant/mutator/node/rescue.rb
+++ b/lib/mutant/mutator/node/rescue.rb
@@ -14,20 +14,14 @@ class Rescue < self
 
         RESCUE_INDICES = (1..-2).freeze
 
-        # Emit mutations
-        #
-        # @return [undefined]
+      private
+
         def dispatch
           mutate_body
           mutate_rescue_bodies
           mutate_else_body
         end
 
-      private
-
-        # Mutate child by name
-        #
-        # @return [undefined]
         def mutate_rescue_bodies
           children_indices(RESCUE_INDICES).each do |index|
             mutate_child(index)
@@ -36,11 +30,6 @@ def mutate_rescue_bodies
           end
         end
 
-        # Emit concatenation with body
-        #
-        # @param [Parser::AST::Node] child
-        #
-        # @return [undefined]
         def emit_concat(child)
           if body
             emit(s(:begin, body, child))
@@ -49,18 +38,12 @@ def emit_concat(child)
           end
         end
 
-        # Emit body mutations
-        #
-        # @return [undefined]
         def mutate_body
           return unless body
           emit_body_mutations
           emit(body)
         end
 
-        # Emit else body mutations
-        #
-        # @return [undefined]
         def mutate_else_body
           return unless else_body
           emit_else_body_mutations
diff --git a/lib/mutant/mutator/node/return.rb b/lib/mutant/mutator/node/return.rb
index d42dc8b27..289f2c630 100644
--- a/lib/mutant/mutator/node/return.rb
+++ b/lib/mutant/mutator/node/return.rb
@@ -12,9 +12,6 @@ class Return < self
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           emit_singletons
           return unless value
diff --git a/lib/mutant/mutator/node/send.rb b/lib/mutant/mutator/node/send.rb
index 75c0690c1..4fe45c44a 100644
--- a/lib/mutant/mutator/node/send.rb
+++ b/lib/mutant/mutator/node/send.rb
@@ -48,9 +48,6 @@ class Send < self
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           emit_singletons
 
@@ -63,23 +60,14 @@ def dispatch
           end
         end
 
-        # AST metadata for node
-        #
-        # @return [AST::Meta::Send]
         def meta
           AST::Meta::Send.new(node)
         end
         memoize :meta
 
-        # Arguments being send
-        #
-        # @return [Enumerable<Parser::AST::Node>]
         alias_method :arguments, :remaining_children
         private :arguments
 
-        # Perform normal, non special case dispatch
-        #
-        # @return [undefined]
         def normal_dispatch
           emit_naked_receiver
           emit_selector_replacement
@@ -90,9 +78,6 @@ def normal_dispatch
           mutate_arguments
         end
 
-        # Emit mutations which only correspond to one selector
-        #
-        # @return [undefined]
         def emit_selector_specific_mutations
           emit_const_get_mutation
           emit_integer_mutation
@@ -101,9 +86,6 @@ def emit_selector_specific_mutations
           emit_lambda_mutation
         end
 
-        # Emit selector mutations specific to top level constants
-        #
-        # @return [undefined]
         def emit_receiver_selector_mutations
           return unless meta.receiver_possible_top_level_const?
 
@@ -113,9 +95,6 @@ def emit_receiver_selector_mutations
             .each(&method(:emit_selector))
         end
 
-        # Emit mutation from `!!foo` to `foo`
-        #
-        # @return [undefined]
         def emit_double_negation_mutation
           return unless selector.equal?(:!) && n_send?(receiver)
 
@@ -123,19 +102,10 @@ def emit_double_negation_mutation
           emit(negated.receiver) if negated.selector.equal?(:!)
         end
 
-        # Emit mutation from proc definition to lambda
-        #
-        # @return [undefined]
         def emit_lambda_mutation
           emit(s(:send, nil, :lambda)) if meta.proc?
         end
 
-        # Emit mutation for `#dig`
-        #
-        # - Mutates `foo.dig(a, b)` to `foo.fetch(a).dig(b)`
-        # - Mutates `foo.dig(a)` to `foo.fetch(a)`
-        #
-        # @return [undefined]
         def emit_dig_mutation
           return if !selector.equal?(:dig) || arguments.none?
 
@@ -148,41 +118,26 @@ def emit_dig_mutation
           emit(s(:send, fetch_mutation, :dig, *tail))
         end
 
-        # Emit mutation from `to_i` to `Integer(...)`
-        #
-        # @return [undefined]
         def emit_integer_mutation
           return unless selector.equal?(:to_i)
 
           emit(s(:send, nil, :Integer, receiver))
         end
 
-        # Emit mutation from `const_get` to const literal
-        #
-        # @return [undefined]
         def emit_const_get_mutation
           return unless selector.equal?(:const_get) && n_sym?(arguments.first)
 
           emit(s(:const, receiver, AST::Meta::Symbol.new(arguments.first).name))
         end
 
-        # Emit selector replacement
-        #
-        # @return [undefined]
         def emit_selector_replacement
           SELECTOR_REPLACEMENTS.fetch(selector, EMPTY_ARRAY).each(&method(:emit_selector))
         end
 
-        # Emit naked receiver mutation
-        #
-        # @return [undefined]
         def emit_naked_receiver
           emit(receiver) if receiver
         end
 
-        # Mutate arguments
-        #
-        # @return [undefined]
         def mutate_arguments
           emit_type(receiver, selector)
           remaining_children_with_index.each do |_node, index|
@@ -191,25 +146,14 @@ def mutate_arguments
           end
         end
 
-        # Mutate argument
-        #
-        # @param [Integer] index
-        #
-        # @return [undefined]
         def mutate_argument_index(index)
           mutate_child(index) { |node| !n_begin?(node) }
         end
 
-        # Emit argument propagation
-        #
-        # @return [undefined]
         def emit_argument_propagation
           emit_propagation(Mutant::Util.one(arguments)) if arguments.one?
         end
 
-        # Emit receiver mutations
-        #
-        # @return [undefined]
         def mutate_receiver
           return unless receiver
           emit_implicit_self
@@ -218,9 +162,6 @@ def mutate_receiver
           end
         end
 
-        # Emit implicit self mutation
-        #
-        # @return [undefined]
         def emit_implicit_self
           emit_receiver(nil) if n_self?(receiver) && !(
             KEYWORDS.include?(selector) ||
diff --git a/lib/mutant/mutator/node/send/attribute_assignment.rb b/lib/mutant/mutator/node/send/attribute_assignment.rb
index 124915d21..b60143846 100644
--- a/lib/mutant/mutator/node/send/attribute_assignment.rb
+++ b/lib/mutant/mutator/node/send/attribute_assignment.rb
@@ -12,26 +12,17 @@ class AttributeAssignment < self
 
         private
 
-          # Emit mutations
-          #
-          # @return [undefined]
           def dispatch
             normal_dispatch
             emit_attribute_read
           end
 
-          # Mutate arguments
-          #
-          # @return [undefined]
           def mutate_arguments
             remaining_children_indices.each do |index|
               mutate_child(index)
             end
           end
 
-          # Emit attribute read
-          #
-          # @return [undefined]
           def emit_attribute_read
             emit_type(receiver, selector[ATTRIBUTE_RANGE].to_sym)
           end
diff --git a/lib/mutant/mutator/node/send/binary.rb b/lib/mutant/mutator/node/send/binary.rb
index 5fefc7925..687168bc6 100644
--- a/lib/mutant/mutator/node/send/binary.rb
+++ b/lib/mutant/mutator/node/send/binary.rb
@@ -12,9 +12,6 @@ class Binary < self
 
         private
 
-          # Emit mutations
-          #
-          # @return [undefined]
           def dispatch
             emit(left)
             emit_left_mutations
@@ -24,9 +21,6 @@ def dispatch
             emit_not_equality_mutations
           end
 
-          # Emit mutations for `!=`
-          #
-          # @return [undefined]
           def emit_not_equality_mutations
             return unless operator.equal?(:'!=')
 
@@ -34,11 +28,6 @@ def emit_not_equality_mutations
             emit_not_equality_mutation(:equal?)
           end
 
-          # Emit negated method sends with specified operator
-          #
-          # @param new_operator [Symbol] selector to be negated
-          #
-          # @return [undefined]
           def emit_not_equality_mutation(new_operator)
             emit(n_not(s(:send, left, new_operator, right)))
           end
diff --git a/lib/mutant/mutator/node/send/conditional.rb b/lib/mutant/mutator/node/send/conditional.rb
index 3631411e7..084d4c436 100644
--- a/lib/mutant/mutator/node/send/conditional.rb
+++ b/lib/mutant/mutator/node/send/conditional.rb
@@ -10,9 +10,6 @@ class Conditional < self
 
         private
 
-          # Emit mutations
-          #
-          # @return [undefined]
           def dispatch
             super()
             emit(s(:send, *children))
diff --git a/lib/mutant/mutator/node/splat.rb b/lib/mutant/mutator/node/splat.rb
index a67bcda4e..1b79dc9a0 100644
--- a/lib/mutant/mutator/node/splat.rb
+++ b/lib/mutant/mutator/node/splat.rb
@@ -12,9 +12,6 @@ class Splat < self
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           emit_singletons
           emit_expression_mutations
diff --git a/lib/mutant/mutator/node/super.rb b/lib/mutant/mutator/node/super.rb
index 89d7fe8c2..e9db4ecd7 100644
--- a/lib/mutant/mutator/node/super.rb
+++ b/lib/mutant/mutator/node/super.rb
@@ -11,9 +11,6 @@ class Super < self
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           emit_singletons
           emit(N_EMPTY_SUPER)
diff --git a/lib/mutant/mutator/node/when.rb b/lib/mutant/mutator/node/when.rb
index d2571184a..bb3ebf625 100644
--- a/lib/mutant/mutator/node/when.rb
+++ b/lib/mutant/mutator/node/when.rb
@@ -11,9 +11,6 @@ class When < self
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           if body
             mutate_body
@@ -23,9 +20,6 @@ def dispatch
           mutate_conditions
         end
 
-        # Emit condition mutations
-        #
-        # @return [undefined]
         def mutate_conditions
           conditions = children.length - 1
           children[0..-2].each_index do |index|
@@ -34,27 +28,14 @@ def mutate_conditions
           end
         end
 
-        # Emit body mutations
-        #
-        # @return [undefined]
         def mutate_body
           mutate_child(body_index)
         end
 
-        # Body node
-        #
-        # @return [Parser::AST::Node]
-        #   if body is present
-        #
-        # @return [nil]
-        #   otherwise
         def body
           children.fetch(body_index)
         end
 
-        # Index of body node
-        #
-        # @return [Integer]
         def body_index
           children.length - 1
         end
diff --git a/lib/mutant/mutator/node/yield.rb b/lib/mutant/mutator/node/yield.rb
index cbe3f6e7e..be84829d5 100644
--- a/lib/mutant/mutator/node/yield.rb
+++ b/lib/mutant/mutator/node/yield.rb
@@ -11,9 +11,6 @@ class Yield < Generic
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           super()
           emit_singletons
diff --git a/lib/mutant/mutator/node/zsuper.rb b/lib/mutant/mutator/node/zsuper.rb
index c0ab43c03..e1918af27 100644
--- a/lib/mutant/mutator/node/zsuper.rb
+++ b/lib/mutant/mutator/node/zsuper.rb
@@ -11,9 +11,6 @@ class ZSuper < self
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           emit_singletons
           emit(N_EMPTY_SUPER)
diff --git a/lib/mutant/mutator/util/array.rb b/lib/mutant/mutator/util/array.rb
index c5710b825..f58468aa1 100644
--- a/lib/mutant/mutator/util/array.rb
+++ b/lib/mutant/mutator/util/array.rb
@@ -12,9 +12,6 @@ class Presence < Util
 
         private
 
-          # Emit element presence mutations
-          #
-          # @return [undefined]
           def dispatch
             input.each_index do |index|
               dup = dup_input
@@ -30,9 +27,6 @@ class Element < Util
 
         private
 
-          # Emit mutations
-          #
-          # @return [undefined]
           def dispatch
             input.each_with_index do |element, index|
               Mutator.mutate(element).each do |mutation|
diff --git a/lib/mutant/mutator/util/symbol.rb b/lib/mutant/mutator/util/symbol.rb
index 6b81106e8..dfaccef45 100644
--- a/lib/mutant/mutator/util/symbol.rb
+++ b/lib/mutant/mutator/util/symbol.rb
@@ -11,9 +11,6 @@ class Symbol < self
 
       private
 
-        # Emit mutations
-        #
-        # @return [undefined]
         def dispatch
           emit((input.to_s + POSTFIX).to_sym)
         end
diff --git a/lib/mutant/parallel.rb b/lib/mutant/parallel.rb
index 9e9f7f66a..5fe3d7992 100644
--- a/lib/mutant/parallel.rb
+++ b/lib/mutant/parallel.rb
@@ -36,24 +36,11 @@ def self.worker(config, **shared)
       )
     end
 
-    # Start threads
-    #
-    # @param [Config] config
-    # @param [Worker] worker
-    #
-    # @return [Array<Thread>]
     def self.threads(config, worker)
       Array.new(config.jobs) { config.thread.new(&worker.method(:call)) }
     end
     private_class_method :threads
 
-    # Create shared variable
-    #
-    # @param [Class] klass
-    # @param [Config] config
-    #
-    # @return [Variable]
-    #
     # ignore :reek:LongParameterList
     def self.shared(klass, config, **attributes)
       klass.new(
diff --git a/lib/mutant/parallel/driver.rb b/lib/mutant/parallel/driver.rb
index f651f2eed..0d540985d 100644
--- a/lib/mutant/parallel/driver.rb
+++ b/lib/mutant/parallel/driver.rb
@@ -27,22 +27,12 @@ def wait_timeout(timeout)
 
     private
 
-      # Possibly finalize the exeuction
-      #
-      # @param [Status]
-      #
-      # @return [Status]
       def finalize(status)
         status.tap do
           threads.each(&:join) if status.done?
         end
       end
 
-      # Get status
-      #
-      # @return [Status]
-      #
-      # ignore :reek:NestedIterators
       def status
         var_active_jobs.with do |active_jobs|
           var_sink.with do |sink|
diff --git a/lib/mutant/parallel/worker.rb b/lib/mutant/parallel/worker.rb
index d23d9081e..b2b102d96 100644
--- a/lib/mutant/parallel/worker.rb
+++ b/lib/mutant/parallel/worker.rb
@@ -39,20 +39,12 @@ def call
 
     private
 
-      # Next job, if any
-      #
-      # @return [Job, nil]
       def next_job
         var_source.with do |source|
           source.next if source.next?
         end
       end
 
-      # Add result
-      #
-      # @param [Object] result
-      #
-      # @return [Boolean]
       def add_result(result)
         var_sink.with do |sink|
           sink.result(result)
@@ -60,32 +52,18 @@ def add_result(result)
         end
       end
 
-      # Register job to be started
-      #
-      # @param [Job] job
-      #
-      # @return [undefined]
       def job_start(job)
         var_active_jobs.with do |active_jobs|
           active_jobs << job
         end
       end
 
-      # Register job to be done
-      #
-      # @param [Job] job
-      # @param [Object] result
-      #
-      # @return [undefined]
       def job_done(job)
         var_active_jobs.with do |active_jobs|
           active_jobs.delete(job)
         end
       end
 
-      # Finalize worker
-      #
-      # @return [undefined]
       def finalize
         var_final.put(nil) if var_running.modify(&:pred).zero?
       end
diff --git a/lib/mutant/reporter/cli.rb b/lib/mutant/reporter/cli.rb
index 0a1c2ab1a..a30bf52c4 100644
--- a/lib/mutant/reporter/cli.rb
+++ b/lib/mutant/reporter/cli.rb
@@ -69,11 +69,6 @@ def report(env)
 
     private
 
-      # Write output frame
-      #
-      # @param [String] frame
-      #
-      # @return [undefined]
       def write(frame)
         output.write(frame)
       end
diff --git a/lib/mutant/reporter/cli/format.rb b/lib/mutant/reporter/cli/format.rb
index 592eded25..f6b7daa8d 100644
--- a/lib/mutant/reporter/cli/format.rb
+++ b/lib/mutant/reporter/cli/format.rb
@@ -49,12 +49,6 @@ class Output
 
       private
 
-        # Format object with printer
-        #
-        # @param [Class:Printer] printer
-        # @param [Object] object
-        #
-        # @return [String]
         def format(printer, object)
           buffer = new_buffer
           printer.call(Output.new(tty, buffer), object)
@@ -84,9 +78,6 @@ def progress(status)
 
         private
 
-          # New buffer
-          #
-          # @return [StringIO]
           def new_buffer
             StringIO.new
           end
diff --git a/lib/mutant/reporter/cli/printer.rb b/lib/mutant/reporter/cli/printer.rb
index 4eded657f..cc0039385 100644
--- a/lib/mutant/reporter/cli/printer.rb
+++ b/lib/mutant/reporter/cli/printer.rb
@@ -44,81 +44,41 @@ def self.define_delegator(name)
 
       private
 
-        # Status color
-        #
-        # @return [Color]
         def status_color
           success? ? Color::GREEN : Color::RED
         end
 
-        # Visit a collection of objects
-        #
-        # @return [Class::Printer] printer
-        # @return [Enumerable<Object>] collection
-        #
-        # @return [undefined]
         def visit_collection(printer, collection)
           collection.each do |object|
             visit(printer, object)
           end
         end
 
-        # Visit object
-        #
-        # @param [Class::Printer] printer
-        # @param [Object] object
-        #
-        # @return [undefined]
         def visit(printer, object)
           printer.call(output, object)
         end
 
-        # Print an info line to output
-        #
-        # @return [undefined]
         def info(string, *arguments)
           puts(string % arguments)
         end
 
-        # Print a status line to output
-        #
-        # @return [undefined]
         def status(string, *arguments)
           puts(colorize(status_color, string % arguments))
         end
 
-        # Print a line to output
-        #
-        # @return [undefined]
         def puts(string)
           output.puts(string)
         end
 
-        # Colorize message
-        #
-        # @param [Color] color
-        # @param [String] message
-        #
-        # @return [String]
-        #   if color is enabled
-        #   unmodified message otherwise
         def colorize(color, message)
           color = Color::NONE unless tty?
           color.format(message)
         end
 
-        # Test if output is a tty
-        #
-        # @return [Boolean]
         def tty?
           output.tty?
         end
 
-        # Test if output can be colored
-        #
-        # @return [Boolean]
-        #
-        # @api private
         alias_method :color?, :tty?
       end # Printer
     end # CLI
diff --git a/lib/mutant/reporter/cli/printer/env_progress.rb b/lib/mutant/reporter/cli/printer/env_progress.rb
index 67cfd4481..2d32b9889 100644
--- a/lib/mutant/reporter/cli/printer/env_progress.rb
+++ b/lib/mutant/reporter/cli/printer/env_progress.rb
@@ -40,29 +40,14 @@ def run
 
         private
 
-          # Mutations processed per second
-          #
-          # @return [Float]
-          #
-          # @api private
           def mutations_per_second
             amount_mutation_results / runtime
           end
 
-          # Coverage in percent
-          #
-          # @return [Float]
-          #
-          # @api private
           def coverage_percent
             coverage * 100
           end
 
-          # Overhead in percent
-          #
-          # @return [Float]
-          #
-          # @api private
           def overhead_percent
             (overhead / killtime) * 100
           end
diff --git a/lib/mutant/reporter/cli/printer/isolation_result.rb b/lib/mutant/reporter/cli/printer/isolation_result.rb
index ce40de17c..39ba58161 100644
--- a/lib/mutant/reporter/cli/printer/isolation_result.rb
+++ b/lib/mutant/reporter/cli/printer/isolation_result.rb
@@ -66,39 +66,24 @@ def run
 
         private
 
-          # Visit successful isolation result
-          #
-          # @return [undefined]
           def visit_success
             visit(TestResult, object.value)
           end
 
-          # Print log messages
-          #
-          # @return [undefined]
           def print_log_messages
             log = object.log
 
             puts(LOG_MESSAGES % log) unless log.empty?
           end
 
-          # Visit child error isolation result
-          #
-          # @return [undefined]
           def visit_child_error
             puts(CHILD_ERROR_MESSAGE % object.value.inspect)
           end
 
-          # Visit fork error isolation result
-          #
-          # @return [undefined]
           def visit_fork_error
             puts(FORK_ERROR_MESSAGE)
           end
 
-          # Visit exception isolation result
-          #
-          # @return [undefined]
           def visit_exception
             exception = object.value
 
@@ -110,9 +95,6 @@ def visit_exception
             )
           end
 
-          # Visit chain
-          #
-          # @return [undefined]
           def visit_chain
             printer = self.class
 
diff --git a/lib/mutant/reporter/cli/printer/mutation_progress_result.rb b/lib/mutant/reporter/cli/printer/mutation_progress_result.rb
index 91c9f701e..41a4bef96 100644
--- a/lib/mutant/reporter/cli/printer/mutation_progress_result.rb
+++ b/lib/mutant/reporter/cli/printer/mutation_progress_result.rb
@@ -18,11 +18,6 @@ def run
 
         private
 
-          # Write colorized char
-          #
-          # @param [String] char
-          #
-          # @return [undefined]
           def char(char)
             output.write(colorize(status_color, char))
           end
diff --git a/lib/mutant/reporter/cli/printer/mutation_result.rb b/lib/mutant/reporter/cli/printer/mutation_result.rb
index a486a3456..b16118cf6 100644
--- a/lib/mutant/reporter/cli/printer/mutation_result.rb
+++ b/lib/mutant/reporter/cli/printer/mutation_result.rb
@@ -59,9 +59,6 @@ def run
 
         private
 
-          # Print mutation details
-          #
-          # @return [undefined]
           def print_details
             __send__(MAP.fetch(mutation.class))
 
@@ -69,9 +66,6 @@ def print_details
             visit_isolation_result
           end
 
-          # Evil mutation details
-          #
-          # @return [String]
           def evil_details
             diff = Diff.build(mutation.original_source, mutation.source)
             diff = color? ? diff.colorized_diff : diff.diff
@@ -82,9 +76,6 @@ def evil_details
             end
           end
 
-          # Print no diff message
-          #
-          # @return [undefined]
           def print_no_diff_message
             info(
               NO_DIFF_MESSAGE,
@@ -95,30 +86,18 @@ def print_no_diff_message
             )
           end
 
-          # Noop details
-          #
-          # @return [String]
           def noop_details
             info(NOOP_MESSAGE)
           end
 
-          # Neutral details
-          #
-          # @return [String]
           def neutral_details
             info(NEUTRAL_MESSAGE, original_node.inspect, mutation.source)
           end
 
-          # Visit failed test results
-          #
-          # @return [undefined]
           def visit_isolation_result
             visit(IsolationResult, isolation_result)
           end
 
-          # Original node
-          #
-          # @return [Parser::AST::Node]
           def original_node
             mutation.subject.node
           end
diff --git a/lib/mutant/reporter/cli/printer/status_progressive.rb b/lib/mutant/reporter/cli/printer/status_progressive.rb
index 6dc0b1402..862d4a7e5 100644
--- a/lib/mutant/reporter/cli/printer/status_progressive.rb
+++ b/lib/mutant/reporter/cli/printer/status_progressive.rb
@@ -35,18 +35,10 @@ def run
 
         private
 
-          # Object being printed
-          #
-          # @return [Result::Env]
           def object
             super().payload
           end
 
-          # Mutations processed per second
-          #
-          # @return [Float]
-          #
-          # @api private
           def mutations_per_second
             amount_mutation_results / runtime
           end
diff --git a/lib/mutant/reporter/cli/printer/subject_progress.rb b/lib/mutant/reporter/cli/printer/subject_progress.rb
index 0a664434b..cd5071d2c 100644
--- a/lib/mutant/reporter/cli/printer/subject_progress.rb
+++ b/lib/mutant/reporter/cli/printer/subject_progress.rb
@@ -32,9 +32,6 @@ def run
 
         private
 
-          # Print stats
-          #
-          # @return [undefined]
           def print_stats
             status(
               FORMAT,
@@ -47,16 +44,10 @@ def print_stats
             )
           end
 
-          # Print progress bar finish
-          #
-          # @return [undefined]
           def print_progress_bar_finish
             puts(nil) unless amount_mutation_results.zero?
           end
 
-          # Print mutation results
-          #
-          # @return [undefined]
           def print_mutation_results
             visit_collection(MutationProgressResult, object.mutation_results)
           end
diff --git a/lib/mutant/repository/diff.rb b/lib/mutant/repository/diff.rb
index 22c4b5155..2587f8888 100644
--- a/lib/mutant/repository/diff.rb
+++ b/lib/mutant/repository/diff.rb
@@ -29,10 +29,6 @@ def touches?(path, line_range)
 
     private
 
-      # Touched paths
-      #
-      # @return [Hash{Pathname => Path}]
-      #
       # rubocop:disable Metrics/MethodLength
       def touched_paths
         pathname = world.pathname
@@ -49,13 +45,8 @@ def touched_paths
           .to_h
       end
       memoize :touched_paths
+      # rubocop:enable Metrics/MethodLength
 
-      # Parse path
-      #
-      # @param [Pathname] work_dir
-      # @param [String] line
-      #
-      # @return [Path]
       def parse_line(work_dir, line)
         match = FORMAT.match(line) or fail Error, "Invalid git diff-index line: #{line}"
 
@@ -88,9 +79,6 @@ def touches?(line_range)
 
       private
 
-        # Ranges of hunks in the diff
-        #
-        # @return [Array<Range<Integer>>]
         def diff_ranges
           world
             .capture_stdout(%W[git diff --unified=0 #{to} -- #{path}])
diff --git a/lib/mutant/repository/diff/ranges.rb b/lib/mutant/repository/diff/ranges.rb
index ec1dc6d84..82f6fa2cf 100644
--- a/lib/mutant/repository/diff/ranges.rb
+++ b/lib/mutant/repository/diff/ranges.rb
@@ -18,11 +18,6 @@ def self.parse(diff)
           diff.lines.flat_map(&method(:parse_ranges)).to_set
         end
 
-        # Parse ranges from line
-        #
-        # @param [String] line
-        #
-        # @return [Array<Range<Integer>>]
         def self.parse_ranges(line)
           match = REGEXP.match(line) or return EMPTY_ARRAY
 
@@ -34,12 +29,6 @@ def self.parse_ranges(line)
         end
         private_class_method :parse_ranges
 
-        # Construct a range from start point and offset
-        #
-        # @param [String] start
-        # @param [String, nil] offset
-        #
-        # @return [Range<Integer>]
         def self.mk_range(start, offset)
           start = Integer(start)
 
diff --git a/lib/mutant/result.rb b/lib/mutant/result.rb
index 0f4706952..d08c54356 100644
--- a/lib/mutant/result.rb
+++ b/lib/mutant/result.rb
@@ -193,9 +193,6 @@ def amount_mutations_alive
 
     private
 
-      # Killed mutation results
-      #
-      # @return [Array<Result::Mutation>]
       def killed_mutation_results
         mutation_results.select(&:success?)
       end
diff --git a/lib/mutant/runner.rb b/lib/mutant/runner.rb
index 3afc82294..0d4d9b667 100644
--- a/lib/mutant/runner.rb
+++ b/lib/mutant/runner.rb
@@ -12,9 +12,6 @@ def self.apply(env)
       Either::Right.new(run_mutation_analysis(env))
     end
 
-    # Run mutation analysis
-    #
-    # @return [undefined]
     def self.run_mutation_analysis(env)
       reporter = reporter(env)
 
@@ -27,13 +24,6 @@ def self.run_mutation_analysis(env)
     end
     private_class_method :run_mutation_analysis
 
-    # Run driver
-    #
-    # @param [Reporter] reporter
-    # @param [Driver] driver
-    #
-    # @return [Object]
-    #   the last returned status payload
     def self.run_driver(reporter, driver)
       loop do
         status = driver.wait_timeout(reporter.delay)
@@ -43,9 +33,6 @@ def self.run_driver(reporter, driver)
     end
     private_class_method :run_driver
 
-    # Configuration for parallel execution engine
-    #
-    # @return [Parallell::Config]
     def self.mutation_test_config(env)
       world = env.world
 
@@ -61,11 +48,6 @@ def self.mutation_test_config(env)
     end
     private_class_method :mutation_test_config
 
-    # Reporter to use
-    #
-    # @param [Env] env
-    #
-    # @return [Reporter]
     def self.reporter(env)
       env.config.reporter
     end
diff --git a/lib/mutant/runner/sink.rb b/lib/mutant/runner/sink.rb
index 8771fd664..15f959356 100644
--- a/lib/mutant/runner/sink.rb
+++ b/lib/mutant/runner/sink.rb
@@ -51,11 +51,6 @@ def result(mutation_result)
 
     private
 
-      # Return previous results
-      #
-      # @param [Subject]
-      #
-      # @return [Array<Result::Mutation>]
       def previous_mutation_results(subject)
         subject_result = @subject_results.fetch(subject) { return EMPTY_ARRAY }
         subject_result.mutation_results
diff --git a/lib/mutant/subject.rb b/lib/mutant/subject.rb
index 2a7ed097a..89160ad83 100644
--- a/lib/mutant/subject.rb
+++ b/lib/mutant/subject.rb
@@ -79,18 +79,10 @@ def source
 
   private
 
-    # Neutral mutation
-    #
-    # @return [Mutation::Neutral]
     def neutral_mutation
       Mutation::Neutral.new(self, wrap_node(node))
     end
 
-    # Wrap node into subject specific container
-    #
-    # @param [Parser::AST::Node] node
-    #
-    # @return [Parser::AST::Node]
     def wrap_node(node)
       node
     end
diff --git a/lib/mutant/subject/method.rb b/lib/mutant/subject/method.rb
index 8ab3995e7..afffebb00 100644
--- a/lib/mutant/subject/method.rb
+++ b/lib/mutant/subject/method.rb
@@ -34,9 +34,6 @@ def match_expressions
 
     private
 
-      # The scope
-      #
-      # @return [Class, Module]
       def scope
         context.scope
       end
diff --git a/lib/mutant/subject/method/instance.rb b/lib/mutant/subject/method/instance.rb
index 662453f51..76b0612a5 100644
--- a/lib/mutant/subject/method/instance.rb
+++ b/lib/mutant/subject/method/instance.rb
@@ -33,11 +33,6 @@ def prepare
 
         private
 
-          # Memoizer node for mutant
-          #
-          # @param [Parser::AST::Node] mutant
-          #
-          # @return [Parser::AST::Node]
           def wrap_node(mutant)
             s(:begin, mutant, s(:send, nil, :memoize, s(:args, s(:sym, name))))
           end
diff --git a/lib/mutant/transform.rb b/lib/mutant/transform.rb
index a75d6e3e3..7cba92521 100644
--- a/lib/mutant/transform.rb
+++ b/lib/mutant/transform.rb
@@ -49,9 +49,6 @@ def trace
 
     private
 
-      # Path representation to error
-      #
-      # @return [String]
       def path
         trace.map { |error| error.transform.slug }.reject(&:empty?).join('/')
       end
@@ -78,23 +75,6 @@ def slug
 
   private
 
-    # Make error from curent context
-    #
-    # @param [Error, nil] cause
-    #   original error, if any
-    #
-    # @param [Object] input
-    #   input that ran into the error
-    #
-    # @param [String] message
-    #   human readable error message
-    #
-    # @param [Transform, nil]
-    #   transform that generated the error from input
-    #
-    # @return [Error]
-    #
-    # ignore :reek:LongParameterList
     def error(cause: nil, input:, message: nil)
       Error.new(
         cause:     cause,
@@ -104,42 +84,18 @@ def error(cause: nil, input:, message: nil)
       )
     end
 
-    # Lift error
-    #
-    # @param [Error]
-    #
-    # @return [Error]
     def lift_error(error)
       error.with(transform: self)
     end
 
-    # Wrap error
-    #
-    # @param [Error]
-    #
-    # @return [Error]
     def wrap_error(error)
       error(cause: error, input: error.input)
     end
 
-    # Create failure
-    #
-    # @param [Object] value
-    #
-    # @return [Either::Left]
-    #
-    # ignore :reek:UtilityFunction
     def failure(value)
       Either::Left.new(value)
     end
 
-    # Create success
-    #
-    # @param [Object] value
-    #
-    # @return [Either::Right]
-    #
-    # ignore :reek:UtilityFunction
     def success(value)
       Either::Right.new(value)
     end
@@ -268,14 +224,6 @@ def apply(input)
 
     private
 
-      # Transform array
-      #
-      # @param [Array<Object>] input
-      #
-      # @return [Either<Error, Array<Object>]
-      #
-      # ignore :reek:NestedIterators
-      #
       # rubocop:disable Metrics/MethodLength
       def run(input)
         output = []
@@ -357,31 +305,16 @@ def apply(input)
 
     private
 
-      # Transform hash
-      #
-      # @param [Hash] input
-      #
-      # @return [Either<Error, Hash>]
       def transform(input)
         transform_required(input).bind do |required|
           transform_optional(input).fmap(&required.method(:merge))
         end
       end
 
-      # Transform required keys
-      #
-      # @param [Hash] input
-      #
-      # @return [Either<Error, Hash>]
       def transform_required(input)
         transform_keys(required, input)
       end
 
-      # Transform optional keys
-      #
-      # @param [Hash] input
-      #
-      # @return [Either<Error, Hash>]
       def transform_optional(input)
         transform_keys(
           optional.select { |key| input.key?(key.value) },
@@ -389,13 +322,6 @@ def transform_optional(input)
         )
       end
 
-      # Transform keys
-      #
-      # @param [Array<Transform::Hash::Key>] keys
-      # @param [Hash] input
-      #
-      # @return [Either<Error, Hash>]
-      #
       # ignore :reek:NestedIterators
       #
       # rubocop:disable Metrics/MethodLength
@@ -415,24 +341,12 @@ def transform_keys(keys, input)
       end
       # rubocop:enable Metrics/MethodLength
 
-      # Coerce key value under key specific transformer
-      #
-      # @param [Hash::Key] key
-      # @param [Hash] input
-      #
-      # @return [Either<Error, Object>]
       def coerce_key(key, input)
         key.apply(input.fetch(key.value)).lmap do |error|
           error(input: input, cause: error)
         end
       end
 
-      # Reject unexpected keys
-      #
-      # @param [Hash]
-      #
-      # @return [Either<Error, Object>]
-      #
       # rubocop:disable Metrics/MethodLength
       def reject_keys(input)
         keys       = input.keys
@@ -452,17 +366,11 @@ def reject_keys(input)
       end
       # rubocop:enable Metrics/MethodLength
 
-      # Key values allowed to be present
-      #
-      # @return [Array<Object>]
       def allowed_keys
         required_keys + optional.map(&:value)
       end
       memoize :allowed_keys
 
-      # Key values required to be present
-      #
-      # @return [Array<Object>]
       def required_keys
         required.map(&:value)
       end
diff --git a/lib/mutant/warnings.rb b/lib/mutant/warnings.rb
index 37ddfa1fc..65698ef90 100644
--- a/lib/mutant/warnings.rb
+++ b/lib/mutant/warnings.rb
@@ -92,9 +92,6 @@ def call
 
   private
 
-    # Hook called when capturing a warning
-    #
-    # @return [undefined]
     def capture(*arguments)
       if @disabled
         @original.call(*arguments)
@@ -103,9 +100,6 @@ def capture(*arguments)
       end
     end
 
-    # Assert warnings capture does not call itself
-    #
-    # Its currently not supported nor intended to be supported.
     def assert_no_recursion
       fail RecursiveUseError unless @disabled
     end
diff --git a/lib/mutant/zombifier.rb b/lib/mutant/zombifier.rb
index feef29188..2a9487bc0 100644
--- a/lib/mutant/zombifier.rb
+++ b/lib/mutant/zombifier.rb
@@ -42,32 +42,20 @@ def self.call(*args)
 
   private
 
-    # Original require method
+    attr_reader :original
+    private :original
     #
     # @return [Method]
-    attr_reader :original
 
-    # Run zombifier
-    #
-    # @return [undefined]
     def call
       @original = require_highjack.call(method(:require))
       require(root_require)
     end
 
-    # Test if logical name is subjected to zombification
-    #
-    # @param [String]
     def include?(logical_name)
       !@zombified.include?(logical_name) && includes =~ logical_name
     end
 
-    # Require file in zombie namespace
-    #
-    # @param [#to_s] logical_name
-    #
-    # @return [Bool]
-    #   true if successful and false if feature already loaded
     def require(logical_name)
       logical_name = logical_name.to_s
       loaded = original.call(logical_name)
@@ -77,14 +65,6 @@ def require(logical_name)
       true
     end
 
-    # Find file by logical path
-    #
-    # @param [String] logical_name
-    #
-    # @return [File]
-    #
-    # @raise [LoadError]
-    #   otherwise
     def find(logical_name)
       file_name = "#{logical_name}.rb"
 
@@ -96,13 +76,6 @@ def find(logical_name)
       fail LoadError, "Cannot find file #{file_name.inspect} in load path"
     end
 
-    # Zombify contents of file
-    #
-    # Probably the 2nd valid use of eval ever. (First one is inserting mutants!).
-    #
-    # @param [Pathname] source_path
-    #
-    # @return [undefined]
     def zombify(source_path)
       kernel.eval(
         Unparser.unparse(namespaced_node(source_path)),
@@ -111,11 +84,6 @@ def zombify(source_path)
       )
     end
 
-    # Namespaced root node
-    #
-    # @param [Pathname] source_path
-    #
-    # @return [Parser::AST::Node]
     def namespaced_node(source_path)
       s(:module, s(:const, nil, namespace), Unparser.parse(source_path.read))
     end
diff --git a/mutant.sh b/mutant.sh
new file mode 100755
index 000000000..2fe586d16
--- /dev/null
+++ b/mutant.sh
@@ -0,0 +1,12 @@
+#/usr/bin/bash -ex
+
+bundle exec mutant                                               \
+  --since HEAD~1                                                 \
+  --zombie                                                       \
+  --ignore-subject Mutant::CLI#add_debug_options                 \
+  --ignore-subject Mutant::Mutator::Node::Argument#skip?         \
+  --ignore-subject Mutant::Mutator::Node::ProcargZero#dispatch   \
+  --ignore-subject Mutant::Mutator::Node::When#mutate_conditions \
+  --ignore-subject Mutant::Zombifier#call                        \
+  --                                                             \
+  'Mutant*'