diff --git a/lib/support_engine/file.rb b/lib/support_engine/file.rb
index 82b167f..c7f7bad 100644
--- a/lib/support_engine/file.rb
+++ b/lib/support_engine/file.rb
@@ -5,7 +5,7 @@ module SupportEngine
   module File
     class << self
       # Regex to select encoding details from file -bi command results
-      CHARSET_DETECT_REGEXP = /charset=(.*)\n/.freeze
+      CHARSET_DETECT_REGEXP = /charset=(.*)\n/
       # Default fallback encoding
       DEFAULT_ENCODING = 'utf-8'
 
diff --git a/lib/support_engine/git.rb b/lib/support_engine/git.rb
index 6ae9487..93daea0 100644
--- a/lib/support_engine/git.rb
+++ b/lib/support_engine/git.rb
@@ -9,7 +9,9 @@ class << self
       # @param local_path [String] local path to which we clone
       # @return [Boolean] true if repository got cloned
       # @raise [Errors::FailedShellCommand] raised when anything went wrong
+      # rubocop:disable Naming/PredicateMethod
       def clone_mirror(remote_path, local_path)
+        # rubocop:enable Naming/PredicateMethod
         Shell.call("git clone --mirror #{remote_path} #{local_path}/.git/")
         Shell.call_in_path(local_path, 'git remote update --prune')
         Shell.call_in_path(local_path, 'git config --bool core.bare false')
@@ -22,7 +24,9 @@ def clone_mirror(remote_path, local_path)
       # @param path [String] path of a current repository build
       # @param ref [String] branch or commit that we want to checkout to
       # @return [Boolean] true if we were able to checkout
+      # rubocop:disable Naming/PredicateMethod
       def checkout(path, ref)
+        # rubocop:enable Naming/PredicateMethod
         result = SupportEngine::Shell.call_in_path(
           path,
           "git checkout #{ref}",
diff --git a/lib/support_engine/git/branch.rb b/lib/support_engine/git/branch.rb
index beeabae..1b21929 100644
--- a/lib/support_engine/git/branch.rb
+++ b/lib/support_engine/git/branch.rb
@@ -28,7 +28,7 @@ class Branch < Base
       DETACH_STRING = 'HEAD detached'
 
       # Regexp to remove the '* ' prefix of current branch
-      CURRENT_BRANCH_SANITIZER = /\A\*\s{1}/.freeze
+      CURRENT_BRANCH_SANITIZER = /\A\*\s{1}/
 
       class << self
         # Detects a given commit branch
@@ -45,13 +45,13 @@ def commit(path, commit_hash)
 
           # If the head points to HEAD it means that the repo is in the detach state
           # and we need to pick the latest ref to get a head branch
-          head = head == 'HEAD' ? sanitize_branch(Ref.latest(path)) : head
+          head = sanitize_branch(Ref.latest(path)) if head == 'HEAD'
 
           candidates = call_in_path!(path, cmd)[:stdout]
-                       .split("\n")
-                       .map { |cand| cand.gsub(CURRENT_BRANCH_SANITIZER, '') }
-                       .map(&:strip)
-                       .tap { |arr| arr.delete_if { |cand| cand.include?(DETACH_STRING) } }
+            .split("\n")
+            .map { |cand| cand.gsub(CURRENT_BRANCH_SANITIZER, '') }
+            .map(&:strip)
+            .tap { |arr| arr.delete_if { |cand| cand.include?(DETACH_STRING) } }
 
           resolve_branch(
             candidates,
@@ -151,7 +151,9 @@ def resolve_branch(each_ref, commit_hash, head)
         # @param commit_hash [String] commit hash we're checking
         # @param head [String] name of the head branch
         # @return [String] origin branch of a commit hash
+        # rubocop:disable Metrics/CyclomaticComplexity, Metrics/PerceivedComplexity
         def resolve_from_origins(origin_refs, commit_hash, head)
+          # rubocop:enable Metrics/CyclomaticComplexity, Metrics/PerceivedComplexity
           # We prioritize head branches as main branches of a commit if they are in the head
           return head if origin_refs.any? do |candidate|
             candidate.include?('origin/HEAD') || candidate.include?("refs/heads/#{head}")
@@ -172,7 +174,7 @@ def resolve_from_origins(origin_refs, commit_hash, head)
           end
 
           # And we pick the first one with and sanitize it to get only the branch name
-          (branch || candidates.first)
+          branch || candidates.first
         end
 
         # When we cannot find branch of a commit hash, we try to find pull request as it probably
@@ -201,7 +203,7 @@ def sanitize_branch(branch)
           raise SupportEngine::Errors::UnknownBranch unless branch
 
           UNWANTED_PREFIXES.each { |prefix| branch.gsub!(/\A#{prefix}/, '') }
-          branch.gsub!(%r{\/head\z}, '') if branch.start_with?('pull/')
+          branch.delete_suffix!('/head') if branch.start_with?('pull/')
 
           branch
         end
diff --git a/lib/support_engine/git/commits.rb b/lib/support_engine/git/commits.rb
index 173f5a7..66ae703 100644
--- a/lib/support_engine/git/commits.rb
+++ b/lib/support_engine/git/commits.rb
@@ -189,7 +189,7 @@ def clean_for_each_ref_results(data, source)
             {
               commit_hash: part2[0],
               committed_at: Time.zone.parse(part1[0]),
-              source: source
+              source:
             }
           end
           data.uniq! { |h| h[:commit_hash] }
diff --git a/lib/support_engine/git/gc.rb b/lib/support_engine/git/gc.rb
index 121babd..44892b1 100644
--- a/lib/support_engine/git/gc.rb
+++ b/lib/support_engine/git/gc.rb
@@ -11,7 +11,9 @@ class << self
         # @raise [SupportEngine::Errors::FailedShellCommand] raised when anything went wrong
         # @example Reset state (watch out - this will reset for real!)
         #   SupportEngine::Git::Gc.reset('./') #=> true
+        # rubocop:disable Naming/PredicateMethod
         def reset(path)
+          # rubocop:enable Naming/PredicateMethod
           Shell::Git.call_in_path(path, :reset, '--hard HEAD')
           Shell::Git.call_in_path(path, :clean, '-f -d')
           true
diff --git a/lib/support_engine/git/log.rb b/lib/support_engine/git/log.rb
index b49726e..9d56898 100644
--- a/lib/support_engine/git/log.rb
+++ b/lib/support_engine/git/log.rb
@@ -61,7 +61,7 @@ def shortstat(path, limit: nil, since: 20.years.ago)
         # @param path [String] path of a current repository build
         # @return [DateTime] datetime of a head commit
         def head_committed_at(path)
-          Time.parse(Shell::Git.call_in_path(path, :log, '-1 --format=%cd').first)
+          Time.zone.parse(Shell::Git.call_in_path(path, :log, '-1 --format=%cd').first)
         end
       end
     end
diff --git a/lib/support_engine/git/ref.rb b/lib/support_engine/git/ref.rb
index fdf6e29..22cf98e 100644
--- a/lib/support_engine/git/ref.rb
+++ b/lib/support_engine/git/ref.rb
@@ -25,11 +25,11 @@ def latest(local_path)
         # @example
         #   Git::Ref.head(<local_path>) #=>
         #     {:stdout=>"develop\n", :stderr=>"", :exit_code=>0}
-        def head(local_path, raise_on_invalid_exit = true)
+        def head(local_path, raise_on_invalid_exit: true)
           Shell.call_in_path(
             local_path,
             'git rev-parse --abbrev-ref HEAD',
-            raise_on_invalid_exit: raise_on_invalid_exit
+            raise_on_invalid_exit:
           )
         end
 
@@ -41,7 +41,7 @@ def head(local_path, raise_on_invalid_exit = true)
         # @example
         #   Git::Ref.head!(<local_path>) #=> develop
         def head!(local_path)
-          result = head(local_path, false)
+          result = head(local_path, raise_on_invalid_exit: false)
           return result[:stdout].strip if head?(result)
 
           Shell.call_in_path(local_path, "git symbolic-ref HEAD #{latest(local_path)}")
@@ -52,13 +52,15 @@ def head!(local_path)
         # @param result [Hash] hash with 3 keys describing output
         #   (stdout, stderr, exit_code)
         # @return [Boolean]
+        # rubocop:disable Rails/NegateInclude
         def head?(result)
-          result[:stderr].empty? || \
+          result[:stderr].empty? ||
             !result[:stderr].include?(
               "fatal: ambiguous argument 'HEAD': " \
               'unknown revision or path not in the working tree'
             )
         end
+        # rubocop:enable Rails/NegateInclude
       end
     end
   end
diff --git a/lib/support_engine/git/repo_builder/base.rb b/lib/support_engine/git/repo_builder/base.rb
index c80a9aa..ec45e73 100644
--- a/lib/support_engine/git/repo_builder/base.rb
+++ b/lib/support_engine/git/repo_builder/base.rb
@@ -13,39 +13,29 @@ module RepoBuilder
       class Base
         class << self
           # @return [String] Where should we put our test dummy repo
-          def location
-            ::File.join(SupportEngine.gem_root, 'tmp', "test_repo_#{name}")
-          end
+          def location = ::File.join(SupportEngine.gem_root, 'tmp', "test_repo_#{name}")
 
           # @return [String] Path to .git folder of our location
-          def location_git
-            ::File.join(location, '.git')
-          end
+          def location_git = ::File.join(location, '.git')
 
           # @return [String] Origin poiting to external location
-          def origin
-            "https://something.origin/#{name}"
-          end
+          def origin = "https://something.origin/#{name}"
 
           # @return [String] Default committer that is git compatible
           # @example
           #   self.committer #=> 'Committer <committer@coditsu.io>'
-          def committer
-            Committer.call
-          end
+          def committer = Committer.call
 
           # @return [String] underscored name of current class without modules
           # @example
           #   self.name #=> 'master_mirror'
-          def name
-            to_s.split('::').last.underscore
-          end
+          def name = to_s.split('::').last.underscore
 
           # @param message [String] commit message that we want to have
           # @param author [String] author details in git compatible format
           # @param committed_at [Time, DateTime] time of a commit (now is the default)
           # @return [String] git commit command with proper message, date and author
-          def commit(message, author: committer, committed_at: Time.now)
+          def commit(message, author: committer, committed_at: Time.current)
             cmd = []
             cmd << "GIT_COMMITTER_DATE='#{committed_at}'"
             cmd << "git commit --no-gpg-sign -m '#{message}'"
@@ -56,9 +46,12 @@ def commit(message, author: committer, committed_at: Time.now)
           # Creates a dummy repository in LOCATION with some commits and branches
           def bootstrap
             destroy
-            SupportEngine::Shell.call(const_get(:BOOTSTRAP_CMD))
+            SupportEngine::Shell.call(bootstrap_cmd)
           end
 
+          # @return [String] Bootstrap command - override in subclasses
+          def bootstrap_cmd = raise NotImplementedError
+
           # Destroys dummy repository directory
           def destroy
             FileUtils.rm_r(location, secure: true) if Dir.exist?(location)
diff --git a/lib/support_engine/git/repo_builder/broken_head_ref.rb b/lib/support_engine/git/repo_builder/broken_head_ref.rb
index 2f1a16f..e0e0f29 100644
--- a/lib/support_engine/git/repo_builder/broken_head_ref.rb
+++ b/lib/support_engine/git/repo_builder/broken_head_ref.rb
@@ -6,27 +6,29 @@ module RepoBuilder
       # Creates repository with no master branch and broken head ref
       class BrokenHeadRef < Base
         # Steps we need to take in order to setup dummy repository
-        BOOTSTRAP_CMD = [
-          "git init #{location}",
-          "cd #{location}",
-          'echo "hash = { \'test\' => 1 }" > master.rb',
-          'git add --all ./',
-          commit('master commit'),
-          'git branch develop',
-          'git checkout develop',
-          'echo "hash = { \'test\' => 2 }" > develop.rb',
-          'git add --all ./',
-          commit('develop commit'),
-          'git branch different-branch',
-          'git checkout different-branch',
-          'touch different-branch.txt',
-          'git add --all ./',
-          commit('different-branch commit'),
-          'git checkout develop',
-          "git remote add origin #{origin}",
-          'git branch -D master',
-          'echo "ref: refs/heads/master" > .git/HEAD'
-        ].join(' && ').freeze
+        def self.bootstrap_cmd
+          [
+            "git init #{location}",
+            "cd #{location}",
+            'echo "hash = { \'test\' => 1 }" > master.rb',
+            'git add --all ./',
+            commit('master commit'),
+            'git branch develop',
+            'git checkout develop',
+            'echo "hash = { \'test\' => 2 }" > develop.rb',
+            'git add --all ./',
+            commit('develop commit'),
+            'git branch different-branch',
+            'git checkout different-branch',
+            'touch different-branch.txt',
+            'git add --all ./',
+            commit('different-branch commit'),
+            'git checkout develop',
+            "git remote add origin #{origin}",
+            'git branch -D master',
+            'echo "ref: refs/heads/master" > .git/HEAD'
+          ].join(' && ')
+        end
       end
     end
   end
diff --git a/lib/support_engine/git/repo_builder/master.rb b/lib/support_engine/git/repo_builder/master.rb
index cbde693..c6eea30 100644
--- a/lib/support_engine/git/repo_builder/master.rb
+++ b/lib/support_engine/git/repo_builder/master.rb
@@ -6,20 +6,22 @@ module RepoBuilder
       # Creates repository with master branch
       class Master < Base
         # Steps we need to take in order to setup dummy repository
-        BOOTSTRAP_CMD = [
-          "git init #{location}",
-          "cd #{location}",
-          'echo "hash = { \'test\' => 1 }" > master.rb',
-          'git add --all ./',
-          commit('master commit', committed_at: 2.days.ago),
-          'git branch different-branch',
-          'git checkout different-branch',
-          'touch different-branch.txt',
-          'git add --all ./',
-          commit('different-branch commit'),
-          'git checkout master',
-          "git remote add origin #{origin}"
-        ].join(' && ').freeze
+        def self.bootstrap_cmd
+          [
+            "git init #{location}",
+            "cd #{location}",
+            'echo "hash = { \'test\' => 1 }" > master.rb',
+            'git add --all ./',
+            commit('master commit', committed_at: 2.days.ago),
+            'git branch different-branch',
+            'git checkout different-branch',
+            'touch different-branch.txt',
+            'git add --all ./',
+            commit('different-branch commit'),
+            'git checkout master',
+            "git remote add origin #{origin}"
+          ].join(' && ')
+        end
       end
     end
   end
diff --git a/lib/support_engine/git/repo_builder/master_bare_mirror.rb b/lib/support_engine/git/repo_builder/master_bare_mirror.rb
index d1f4c9b..2b72458 100644
--- a/lib/support_engine/git/repo_builder/master_bare_mirror.rb
+++ b/lib/support_engine/git/repo_builder/master_bare_mirror.rb
@@ -6,7 +6,9 @@ module RepoBuilder
       # Creates new mirror repository from master repository
       class MasterBareMirror < Base
         # Steps we need to take in order to setup dummy repository with --mirror
-        BOOTSTRAP_CMD = "git clone --mirror #{Master.location} #{location}/.git/"
+        def self.bootstrap_cmd
+          "git clone --mirror #{Master.location} #{location}/.git/"
+        end
       end
     end
   end
diff --git a/lib/support_engine/git/repo_builder/master_multiple_committers.rb b/lib/support_engine/git/repo_builder/master_multiple_committers.rb
index 1202f44..1098823 100644
--- a/lib/support_engine/git/repo_builder/master_multiple_committers.rb
+++ b/lib/support_engine/git/repo_builder/master_multiple_committers.rb
@@ -6,26 +6,28 @@ module RepoBuilder
       # Creates repository with master branch and multiple committers
       class MasterMultipleCommitters < Base
         # Steps we need to take in order to setup dummy repository
-        BOOTSTRAP_CMD = [
-          "git init #{location}",
-          "cd #{location}",
-          'echo "hash = { \'test\' => 1 }" > master.rb',
-          'git add --all ./',
-          commit('master commit'),
-          'echo "hash = { \'test\' => 2 }" > master.rb',
-          'git add --all ./',
-          commit('master commit committer2', author: 'Committer2 <committer2@coditsu.io>'),
-          'echo "hash = { \'test\' => 3 }" > master.rb',
-          'git add --all ./',
-          commit('master commit committer3', author: 'Committer3 <committer3@coditsu.io>'),
-          'git branch different-branch',
-          'git checkout different-branch',
-          'touch different-branch.txt',
-          'git add --all ./',
-          commit('different-branch commit'),
-          'git checkout master',
-          "git remote add origin #{origin}"
-        ].join(' && ').freeze
+        def self.bootstrap_cmd
+          [
+            "git init #{location}",
+            "cd #{location}",
+            'echo "hash = { \'test\' => 1 }" > master.rb',
+            'git add --all ./',
+            commit('master commit'),
+            'echo "hash = { \'test\' => 2 }" > master.rb',
+            'git add --all ./',
+            commit('master commit committer2', author: 'Committer2 <committer2@coditsu.io>'),
+            'echo "hash = { \'test\' => 3 }" > master.rb',
+            'git add --all ./',
+            commit('master commit committer3', author: 'Committer3 <committer3@coditsu.io>'),
+            'git branch different-branch',
+            'git checkout different-branch',
+            'touch different-branch.txt',
+            'git add --all ./',
+            commit('different-branch commit'),
+            'git checkout master',
+            "git remote add origin #{origin}"
+          ].join(' && ')
+        end
       end
     end
   end
diff --git a/lib/support_engine/git/repo_builder/master_only.rb b/lib/support_engine/git/repo_builder/master_only.rb
index 50ee694..1dc11ed 100644
--- a/lib/support_engine/git/repo_builder/master_only.rb
+++ b/lib/support_engine/git/repo_builder/master_only.rb
@@ -6,20 +6,22 @@ module RepoBuilder
       # Creates repository with master branch only
       class MasterOnly < Base
         # Steps we need to take in order to setup dummy repository
-        BOOTSTRAP_CMD = [
-          "git init #{location}",
-          "cd #{location}",
-          'echo "hash = { \'test\' => 1 }" > master.rb',
-          'git add --all ./',
-          commit('master commit', committed_at: 2.days.ago),
-          'echo "hash = { \'test\' => 2 }" > master.rb',
-          'git add --all ./',
-          commit('master commit 2', committed_at: 1.days.ago),
-          'echo "hash = { \'test\' => 3 }" > master.rb',
-          'git add --all ./',
-          commit('master commit 3', committed_at: 0.days.ago),
-          "git remote add origin #{origin}"
-        ].join(' && ').freeze
+        def self.bootstrap_cmd
+          [
+            "git init #{location}",
+            "cd #{location}",
+            'echo "hash = { \'test\' => 1 }" > master.rb',
+            'git add --all ./',
+            commit('master commit', committed_at: 2.days.ago),
+            'echo "hash = { \'test\' => 2 }" > master.rb',
+            'git add --all ./',
+            commit('master commit 2', committed_at: 1.day.ago),
+            'echo "hash = { \'test\' => 3 }" > master.rb',
+            'git add --all ./',
+            commit('master commit 3', committed_at: 0.days.ago),
+            "git remote add origin #{origin}"
+          ].join(' && ')
+        end
       end
     end
   end
diff --git a/lib/support_engine/git/repo_builder/master_with_big_branch.rb b/lib/support_engine/git/repo_builder/master_with_big_branch.rb
index 4087cd9..3dea137 100644
--- a/lib/support_engine/git/repo_builder/master_with_big_branch.rb
+++ b/lib/support_engine/git/repo_builder/master_with_big_branch.rb
@@ -17,18 +17,20 @@ def self.create_commits
         end
 
         # Steps we need to take in order to setup dummy repository
-        BOOTSTRAP_CMD = [
-          "git init #{location}",
-          "cd #{location}",
-          'echo "hash = { \'test\' => 1 }" > master.rb',
-          'git add --all ./',
-          commit('master commit', committed_at: 30.days.ago),
-          'git branch different-branch',
-          'git checkout different-branch',
-          create_commits,
-          'git checkout master',
-          "git remote add origin #{origin}"
-        ].join(' && ').freeze
+        def self.bootstrap_cmd
+          [
+            "git init #{location}",
+            "cd #{location}",
+            'echo "hash = { \'test\' => 1 }" > master.rb',
+            'git add --all ./',
+            commit('master commit', committed_at: 30.days.ago),
+            'git branch different-branch',
+            'git checkout different-branch',
+            create_commits,
+            'git checkout master',
+            "git remote add origin #{origin}"
+          ].join(' && ')
+        end
       end
     end
   end
diff --git a/lib/support_engine/git/repo_builder/master_with_big_branch60.rb b/lib/support_engine/git/repo_builder/master_with_big_branch60.rb
index 63b13e8..676a882 100644
--- a/lib/support_engine/git/repo_builder/master_with_big_branch60.rb
+++ b/lib/support_engine/git/repo_builder/master_with_big_branch60.rb
@@ -17,18 +17,20 @@ def self.create_commits
         end
 
         # Steps we need to take in order to setup dummy repository
-        BOOTSTRAP_CMD = [
-          "git init #{location}",
-          "cd #{location}",
-          'echo "hash = { \'test\' => 1 }" > master.rb',
-          'git add --all ./',
-          commit('master commit', committed_at: 90.days.ago),
-          'git branch different-branch',
-          'git checkout different-branch',
-          create_commits,
-          'git checkout master',
-          "git remote add origin #{origin}"
-        ].join(' && ').freeze
+        def self.bootstrap_cmd
+          [
+            "git init #{location}",
+            "cd #{location}",
+            'echo "hash = { \'test\' => 1 }" > master.rb',
+            'git add --all ./',
+            commit('master commit', committed_at: 90.days.ago),
+            'git branch different-branch',
+            'git checkout different-branch',
+            create_commits,
+            'git checkout master',
+            "git remote add origin #{origin}"
+          ].join(' && ')
+        end
       end
     end
   end
diff --git a/lib/support_engine/git/repo_builder/master_with_history.rb b/lib/support_engine/git/repo_builder/master_with_history.rb
index 6b3297b..408929d 100644
--- a/lib/support_engine/git/repo_builder/master_with_history.rb
+++ b/lib/support_engine/git/repo_builder/master_with_history.rb
@@ -9,7 +9,7 @@ class MasterWithHistory < Base
         def self.create_commits
           30.downto(0).flat_map do |number|
             [
-              "echo \"hash = { \'test\' => #{number} }\" > master.rb",
+              "echo \"hash = { 'test' => #{number} }\" > master.rb",
               'git add --all ./',
               commit("master commit #{number}", committed_at: number.days.ago),
               "git branch different-branch-#{number}",
@@ -23,13 +23,15 @@ def self.create_commits
         end
 
         # Steps we need to take in order to setup dummy repository
-        BOOTSTRAP_CMD = [
-          "git init #{location}",
-          "cd #{location}",
-          create_commits,
-          'git checkout master',
-          "git remote add origin #{origin}"
-        ].join(' && ').freeze
+        def self.bootstrap_cmd
+          [
+            "git init #{location}",
+            "cd #{location}",
+            create_commits,
+            'git checkout master',
+            "git remote add origin #{origin}"
+          ].join(' && ')
+        end
       end
     end
   end
diff --git a/lib/support_engine/git/repo_builder/master_with_weird_branch.rb b/lib/support_engine/git/repo_builder/master_with_weird_branch.rb
index 980987e..29362db 100644
--- a/lib/support_engine/git/repo_builder/master_with_weird_branch.rb
+++ b/lib/support_engine/git/repo_builder/master_with_weird_branch.rb
@@ -17,18 +17,20 @@ def self.create_commits
         end
 
         # Steps we need to take in order to setup dummy repository
-        BOOTSTRAP_CMD = [
-          "git init #{location}",
-          "cd #{location}",
-          'echo "hash = { \'test\' => 1 }" > master.rb',
-          'git add --all ./',
-          commit('master commit', committed_at: 30.days.ago),
-          'git branch \'#w@eird-branch\'',
-          'git checkout \'#w@eird-branch\'',
-          create_commits,
-          'git checkout master',
-          "git remote add origin #{origin}"
-        ].join(' && ').freeze
+        def self.bootstrap_cmd
+          [
+            "git init #{location}",
+            "cd #{location}",
+            'echo "hash = { \'test\' => 1 }" > master.rb',
+            'git add --all ./',
+            commit('master commit', committed_at: 30.days.ago),
+            'git branch \'#w@eird-branch\'',
+            'git checkout \'#w@eird-branch\'',
+            create_commits,
+            'git checkout master',
+            "git remote add origin #{origin}"
+          ].join(' && ')
+        end
       end
     end
   end
diff --git a/lib/support_engine/git/repo_builder/no_master.rb b/lib/support_engine/git/repo_builder/no_master.rb
index 78468c0..48cfa44 100644
--- a/lib/support_engine/git/repo_builder/no_master.rb
+++ b/lib/support_engine/git/repo_builder/no_master.rb
@@ -6,26 +6,28 @@ module RepoBuilder
       # Creates repository with no master branch
       class NoMaster < Base
         # Steps we need to take in order to setup dummy repository
-        BOOTSTRAP_CMD = [
-          "git init #{location}",
-          "cd #{location}",
-          'echo "hash = { \'test\' => 1 }" > master.rb',
-          'git add --all ./',
-          commit('master commit'),
-          'git branch develop',
-          'git checkout develop',
-          'echo "hash = { \'test\' => 2 }" > develop.rb',
-          'git add --all ./',
-          commit('develop commit'),
-          'git branch different-branch',
-          'git checkout different-branch',
-          'touch different-branch.txt',
-          'git add --all ./',
-          commit('different-branch commit'),
-          'git checkout develop',
-          "git remote add origin #{origin}",
-          'git branch -D master'
-        ].join(' && ').freeze
+        def self.bootstrap_cmd
+          [
+            "git init #{location}",
+            "cd #{location}",
+            'echo "hash = { \'test\' => 1 }" > master.rb',
+            'git add --all ./',
+            commit('master commit'),
+            'git branch develop',
+            'git checkout develop',
+            'echo "hash = { \'test\' => 2 }" > develop.rb',
+            'git add --all ./',
+            commit('develop commit'),
+            'git branch different-branch',
+            'git checkout different-branch',
+            'touch different-branch.txt',
+            'git add --all ./',
+            commit('different-branch commit'),
+            'git checkout develop',
+            "git remote add origin #{origin}",
+            'git branch -D master'
+          ].join(' && ')
+        end
       end
     end
   end
diff --git a/lib/support_engine/git/repo_builder/outdated_gems.rb b/lib/support_engine/git/repo_builder/outdated_gems.rb
index ffd2ebf..c78ad8d 100644
--- a/lib/support_engine/git/repo_builder/outdated_gems.rb
+++ b/lib/support_engine/git/repo_builder/outdated_gems.rb
@@ -42,15 +42,17 @@ def gemfile_lock
         end
 
         # Steps we need to take in order to setup dummy repository
-        BOOTSTRAP_CMD = [
-          "git init #{location}",
-          "cd #{location}",
-          "printf \"#{gemfile}\" > Gemfile",
-          "printf \"#{gemfile_lock}\" > Gemfile.lock",
-          'git add --all ./',
-          commit('master commit'),
-          "git remote add origin #{origin}"
-        ].join(' && ').freeze
+        def self.bootstrap_cmd
+          [
+            "git init #{location}",
+            "cd #{location}",
+            "printf \"#{gemfile}\" > Gemfile",
+            "printf \"#{gemfile_lock}\" > Gemfile.lock",
+            'git add --all ./',
+            commit('master commit'),
+            "git remote add origin #{origin}"
+          ].join(' && ')
+        end
       end
     end
   end
diff --git a/lib/support_engine/git/repo_builder/outdated_gems_strict.rb b/lib/support_engine/git/repo_builder/outdated_gems_strict.rb
index f789966..57bfb18 100644
--- a/lib/support_engine/git/repo_builder/outdated_gems_strict.rb
+++ b/lib/support_engine/git/repo_builder/outdated_gems_strict.rb
@@ -42,15 +42,17 @@ def gemfile_lock
         end
 
         # Steps we need to take in order to setup dummy repository
-        BOOTSTRAP_CMD = [
-          "git init #{location}",
-          "cd #{location}",
-          "printf \"#{gemfile}\" > Gemfile",
-          "printf \"#{gemfile_lock}\" > Gemfile.lock",
-          'git add --all ./',
-          commit('master commit'),
-          "git remote add origin #{origin}"
-        ].join(' && ').freeze
+        def self.bootstrap_cmd
+          [
+            "git init #{location}",
+            "cd #{location}",
+            "printf \"#{gemfile}\" > Gemfile",
+            "printf \"#{gemfile_lock}\" > Gemfile.lock",
+            'git add --all ./',
+            commit('master commit'),
+            "git remote add origin #{origin}"
+          ].join(' && ')
+        end
       end
     end
   end
diff --git a/lib/support_engine/git/repo_builder/private_gem.rb b/lib/support_engine/git/repo_builder/private_gem.rb
index 06e9e55..559a556 100644
--- a/lib/support_engine/git/repo_builder/private_gem.rb
+++ b/lib/support_engine/git/repo_builder/private_gem.rb
@@ -47,15 +47,17 @@ def gemfile_lock
         end
 
         # Steps we need to take in order to setup dummy repository
-        BOOTSTRAP_CMD = [
-          "git init #{location}",
-          "cd #{location}",
-          "printf \"#{gemfile}\" > Gemfile",
-          "printf \"#{gemfile_lock}\" > Gemfile.lock",
-          'git add --all ./',
-          commit('master commit'),
-          "git remote add origin #{origin}"
-        ].join(' && ').freeze
+        def self.bootstrap_cmd
+          [
+            "git init #{location}",
+            "cd #{location}",
+            "printf \"#{gemfile}\" > Gemfile",
+            "printf \"#{gemfile_lock}\" > Gemfile.lock",
+            'git add --all ./',
+            commit('master commit'),
+            "git remote add origin #{origin}"
+          ].join(' && ')
+        end
       end
     end
   end
diff --git a/lib/support_engine/git/repo_builder/yarn.rb b/lib/support_engine/git/repo_builder/yarn.rb
index 48c14c1..5185c48 100644
--- a/lib/support_engine/git/repo_builder/yarn.rb
+++ b/lib/support_engine/git/repo_builder/yarn.rb
@@ -6,21 +6,23 @@ module RepoBuilder
       # Creates repository with yarn and cloc installed, so we can test yarn run command
       class Yarn < Base
         # Steps we need to take in order to setup dummy repository
-        BOOTSTRAP_CMD = [
-          "git init #{location}",
-          "cd #{location}",
-          'yarn init -y',
-          'yarn add cloc',
-          'git add --all ./',
-          commit('master commit'),
-          'git branch different-branch',
-          'git checkout different-branch',
-          'touch different-branch.txt',
-          'git add --all ./',
-          commit('different-branch commit'),
-          'git checkout master',
-          "git remote add origin #{origin}"
-        ].join(' && ').freeze
+        def self.bootstrap_cmd
+          [
+            "git init #{location}",
+            "cd #{location}",
+            'yarn init -y',
+            'yarn add cloc',
+            'git add --all ./',
+            commit('master commit'),
+            'git branch different-branch',
+            'git checkout different-branch',
+            'touch different-branch.txt',
+            'git add --all ./',
+            commit('different-branch commit'),
+            'git checkout master',
+            "git remote add origin #{origin}"
+          ].join(' && ')
+        end
       end
     end
   end
diff --git a/lib/support_engine/rspec_locator.rb b/lib/support_engine/rspec_locator.rb
index 1e8a9ef..69931e9 100644
--- a/lib/support_engine/rspec_locator.rb
+++ b/lib/support_engine/rspec_locator.rb
@@ -3,7 +3,7 @@
 %w[
   active_support/inflector
   fileutils
-].each(&method(:require))
+].each { require(it) }
 
 module SupportEngine
   # RSpec extension for the `RSpec.describe` subject class auto-discovery
@@ -15,6 +15,7 @@ module SupportEngine
   class RSpecLocator < Module
     # @param  spec_helper_file_path [String] path to the spec_helper.rb file
     def initialize(spec_helper_file_path)
+      super()
       @specs_root_dir = ::File.dirname(spec_helper_file_path)
     end
 
@@ -29,12 +30,12 @@ def extended(rspec)
       # out the proper class that we want to describe
       # @param block [Proc] block with specs
       rspec.define_singleton_method :describe_current do |&block|
-        describe(this.inherited, &block)
+        describe(this.described_class_from_path, &block)
       end
     end
 
     # @return [Class] class name for the RSpec `#describe` method
-    def inherited
+    def described_class_from_path
       caller(2..2)
         .first
         .split(':')
@@ -43,7 +44,7 @@ def inherited
         .gsub('_spec.rb', '')
         .split('/')
         .delete_if(&:empty?)
-        .itself[1..-1]
+        .itself[1..]
         .join('/')
         .camelize
         .constantize
diff --git a/lib/support_engine/shell.rb b/lib/support_engine/shell.rb
index 2297073..9f07407 100644
--- a/lib/support_engine/shell.rb
+++ b/lib/support_engine/shell.rb
@@ -38,15 +38,10 @@ def call(command_with_options, raise_on_invalid_exit: true)
       # @return [Hash] hash with 3 keys describing output (stdout, stderr, exit_code)
       def call_in_path(path, command, raise_on_invalid_exit: true)
         command = ['cd', path.to_s.shellescape, '&&', command]
-        call(command.join(' '), raise_on_invalid_exit: raise_on_invalid_exit)
+        call(command.join(' '), raise_on_invalid_exit:)
       end
 
-      # Escapes any dangerous parameters so we can use a string in a safe way in shell
-      # @param shell_string [String] string that we want to escape
-      # @return [String] safe shell parameter string
-      def escape(shell_string)
-        Shellwords.escape(shell_string)
-      end
+      delegate :escape, to: Shellwords
     end
   end
 end
diff --git a/lib/support_engine/shell/git.rb b/lib/support_engine/shell/git.rb
index 392afd9..c54888d 100644
--- a/lib/support_engine/shell/git.rb
+++ b/lib/support_engine/shell/git.rb
@@ -17,7 +17,7 @@ class << self
         def call_in_path(path, command, options, raise_on_invalid_exit: true)
           result = SupportEngine::Shell::Utf8.call(
             "git -C #{path} #{command} #{options}",
-            raise_on_invalid_exit: raise_on_invalid_exit
+            raise_on_invalid_exit:
           )
 
           result[:stdout].split("\n")
diff --git a/lib/support_engine/shell/utf8.rb b/lib/support_engine/shell/utf8.rb
index a80c4d4..e7836f9 100644
--- a/lib/support_engine/shell/utf8.rb
+++ b/lib/support_engine/shell/utf8.rb
@@ -16,7 +16,7 @@ def call(command_with_options, raise_on_invalid_exit: true)
           encode(
             Shell.call(
               command_with_options,
-              raise_on_invalid_exit: raise_on_invalid_exit
+              raise_on_invalid_exit:
             )
           )
         end
@@ -30,7 +30,7 @@ def call_in_path(path, command, raise_on_invalid_exit: true)
             Shell.call_in_path(
               path,
               command,
-              raise_on_invalid_exit: raise_on_invalid_exit
+              raise_on_invalid_exit:
             )
           )
         end
diff --git a/lib/support_engine/shell/yarn.rb b/lib/support_engine/shell/yarn.rb
index ec992f4..ebc8539 100644
--- a/lib/support_engine/shell/yarn.rb
+++ b/lib/support_engine/shell/yarn.rb
@@ -13,7 +13,7 @@ class << self
         def call(command, options, raise_on_invalid_exit: true)
           Shell::Utf8.call(
             "yarn run --silent #{command} #{options}",
-            raise_on_invalid_exit: raise_on_invalid_exit
+            raise_on_invalid_exit:
           )
         end
 
@@ -26,7 +26,7 @@ def call_in_path(path, command, options, raise_on_invalid_exit: true)
           Shell::Utf8.call_in_path(
             path,
             "yarn run --silent #{command} #{options}",
-            raise_on_invalid_exit: raise_on_invalid_exit
+            raise_on_invalid_exit:
           )
         end
       end
diff --git a/spec/lib/support_engine/git/branch_spec.rb b/spec/lib/support_engine/git/branch_spec.rb
index 79c47a7..dd1e839 100644
--- a/spec/lib/support_engine/git/branch_spec.rb
+++ b/spec/lib/support_engine/git/branch_spec.rb
@@ -1,5 +1,6 @@
 # frozen_string_literal: true
 
+# rubocop:disable Capybara/FindAllFirst
 RSpec.describe_current do
   let(:commits_scope) { SupportEngine::Git::Commits }
   let(:path) { SupportEngine::Git::RepoBuilder::Master.location }
@@ -55,7 +56,7 @@
     context 'when master with branch' do
       let(:path) { SupportEngine::Git::RepoBuilder::Master.location }
       let(:branch) { 'master' }
-      let(:commit_hash) { commits_scope.all(path, branch: branch).first[:commit_hash] }
+      let(:commit_hash) { commits_scope.all(path, branch:).first[:commit_hash] }
 
       before { SupportEngine::Git::RepoBuilder::Master.bootstrap }
 
@@ -79,7 +80,7 @@
     context 'when master branch only' do
       let(:branch) { 'master' }
       let(:path) { SupportEngine::Git::RepoBuilder::MasterOnly.location }
-      let(:commit_hash) { commits_scope.all(path, branch: branch).first[:commit_hash] }
+      let(:commit_hash) { commits_scope.all(path, branch:).first[:commit_hash] }
 
       before { SupportEngine::Git::RepoBuilder::MasterOnly.bootstrap }
 
@@ -137,3 +138,4 @@
     end
   end
 end
+# rubocop:enable Capybara/FindAllFirst
diff --git a/spec/lib/support_engine/git/commits_spec.rb b/spec/lib/support_engine/git/commits_spec.rb
index b3502d4..f901f0b 100644
--- a/spec/lib/support_engine/git/commits_spec.rb
+++ b/spec/lib/support_engine/git/commits_spec.rb
@@ -39,9 +39,9 @@
 
     context 'when we want limited number of commits by time' do
       # on local machines timezone is in CET and Time.zone.now returns UTC
-      subject(:all) { described_class.all(path, since: since) }
+      subject(:all) { described_class.all(path, since:) }
 
-      let(:since) { Time.zone.now + 6.hours }
+      let(:since) { 6.hours.from_now }
       let(:path) { SupportEngine::Git::RepoBuilder::MasterMirror.location }
 
       # There won't be any commits from now
@@ -73,7 +73,7 @@
   end
 
   describe '.latest_by_day' do
-    subject(:latest_by_day) { described_class.latest_by_day(path, limit: limit) }
+    subject(:latest_by_day) { described_class.latest_by_day(path, limit:) }
 
     let(:limit) { nil }
 
diff --git a/spec/lib/support_engine/git/gc_spec.rb b/spec/lib/support_engine/git/gc_spec.rb
index 99db13b..1eed288 100644
--- a/spec/lib/support_engine/git/gc_spec.rb
+++ b/spec/lib/support_engine/git/gc_spec.rb
@@ -6,13 +6,13 @@
 
     context 'when some files were introduced' do
       let(:path) { SupportEngine::Git::RepoBuilder::Master.location }
-      let(:introduced_file_name1) { rand.to_s }
-      let(:introduced_file_name2) { rand.to_s }
+      let(:first_introduced_file) { rand.to_s }
+      let(:second_introduced_file) { rand.to_s }
       let(:introduced) { SupportEngine::Git::Status.introduced(path) }
 
       before do
-        `echo change >> #{File.join(path, introduced_file_name1)}`
-        `echo change >> #{File.join(path, introduced_file_name2)}`
+        `echo change >> #{File.join(path, first_introduced_file)}`
+        `echo change >> #{File.join(path, second_introduced_file)}`
         reset
       end
 
diff --git a/spec/lib/support_engine/git/ref_spec.rb b/spec/lib/support_engine/git/ref_spec.rb
index e71f83e..6a250ed 100644
--- a/spec/lib/support_engine/git/ref_spec.rb
+++ b/spec/lib/support_engine/git/ref_spec.rb
@@ -29,7 +29,7 @@
     end
 
     context 'when raise_on_invalid_exit false' do
-      subject(:head) { described_class.head(path, false) }
+      subject(:head) { described_class.head(path, raise_on_invalid_exit: false) }
 
       let(:path) { SupportEngine::Git::RepoBuilder::BrokenHeadRef.location }
 
@@ -66,7 +66,7 @@
   end
 
   describe '#head?' do
-    subject(:head?) { described_class.head?(described_class.head(path, false)) }
+    subject(:head?) { described_class.head?(described_class.head(path, raise_on_invalid_exit: false)) }
 
     context 'when valid head ref' do
       let(:path) { SupportEngine::Git::RepoBuilder::Master.location }
diff --git a/spec/lib/support_engine/git/repo_builder/base_spec.rb b/spec/lib/support_engine/git/repo_builder/base_spec.rb
index 85274d7..aa56e95 100644
--- a/spec/lib/support_engine/git/repo_builder/base_spec.rb
+++ b/spec/lib/support_engine/git/repo_builder/base_spec.rb
@@ -33,12 +33,14 @@
 
     let(:command) { 'command' }
 
-    before { described_class.const_set(:BOOTSTRAP_CMD, command) }
+    before { allow(described_class).to receive(:bootstrap_cmd).and_return(command) }
 
-    it 'expect to  call, destroy and match shell result' do
-      expect(described_class).to receive(:destroy)
-      expect(SupportEngine::Shell).to receive(:call).with(command).and_return('test')
+    it 'expect to call, destroy and match shell result' do
+      allow(described_class).to receive(:destroy)
+      allow(SupportEngine::Shell).to receive(:call).with(command).and_return('test')
       expect(bootstrap).to eq('test')
+      expect(described_class).to have_received(:destroy)
+      expect(SupportEngine::Shell).to have_received(:call).with(command)
     end
   end
 
@@ -60,8 +62,9 @@
 
     context 'when dir does not exist' do
       it 'expect not to try to remove it' do
-        expect(FileUtils).not_to receive(:rm_r)
+        allow(FileUtils).to receive(:rm_r)
         destroy
+        expect(FileUtils).not_to have_received(:rm_r)
       end
     end
   end
diff --git a/spec/lib/support_engine/git/repo_builder/broken_head_ref_mirror_spec.rb b/spec/lib/support_engine/git/repo_builder/broken_head_ref_mirror_spec.rb
index 7494baf..4afd730 100644
--- a/spec/lib/support_engine/git/repo_builder/broken_head_ref_mirror_spec.rb
+++ b/spec/lib/support_engine/git/repo_builder/broken_head_ref_mirror_spec.rb
@@ -12,9 +12,11 @@
     end
 
     it 'expect to remove previous repo, clone mirror to a new one and return clone path' do
-      expect(described_class).to receive(:destroy)
-      expect(SupportEngine::Git).to receive(:clone_mirror).with(*clone_args).and_return('test')
+      allow(described_class).to receive(:destroy)
+      allow(SupportEngine::Git).to receive(:clone_mirror).with(*clone_args).and_return('test')
       expect(bootstrap).to eq('test')
+      expect(described_class).to have_received(:destroy)
+      expect(SupportEngine::Git).to have_received(:clone_mirror).with(*clone_args)
     end
   end
 end
diff --git a/spec/lib/support_engine/git/repo_builder/broken_head_ref_spec.rb b/spec/lib/support_engine/git/repo_builder/broken_head_ref_spec.rb
index 694f050..aa784ca 100644
--- a/spec/lib/support_engine/git/repo_builder/broken_head_ref_spec.rb
+++ b/spec/lib/support_engine/git/repo_builder/broken_head_ref_spec.rb
@@ -1,15 +1,17 @@
 # frozen_string_literal: true
 
 RSpec.describe_current do
-  describe 'BOOTSTRAP_CMD' do
+  describe '.bootstrap_cmd' do
     subject(:bootstrap) { described_class.bootstrap }
 
-    let(:shell_args) { described_class::BOOTSTRAP_CMD }
+    let(:shell_args) { described_class.bootstrap_cmd }
 
     it 'expect to remove previous repo, build new and return path to it' do
-      expect(described_class).to receive(:destroy)
-      expect(SupportEngine::Shell).to receive(:call).with(shell_args).and_return('test')
+      allow(described_class).to receive(:destroy)
+      allow(SupportEngine::Shell).to receive(:call).with(shell_args).and_return('test')
       expect(bootstrap).to eq('test')
+      expect(described_class).to have_received(:destroy)
+      expect(SupportEngine::Shell).to have_received(:call).with(shell_args)
     end
   end
 end
diff --git a/spec/lib/support_engine/git/repo_builder/master_bare_mirror_spec.rb b/spec/lib/support_engine/git/repo_builder/master_bare_mirror_spec.rb
index 694f050..aa784ca 100644
--- a/spec/lib/support_engine/git/repo_builder/master_bare_mirror_spec.rb
+++ b/spec/lib/support_engine/git/repo_builder/master_bare_mirror_spec.rb
@@ -1,15 +1,17 @@
 # frozen_string_literal: true
 
 RSpec.describe_current do
-  describe 'BOOTSTRAP_CMD' do
+  describe '.bootstrap_cmd' do
     subject(:bootstrap) { described_class.bootstrap }
 
-    let(:shell_args) { described_class::BOOTSTRAP_CMD }
+    let(:shell_args) { described_class.bootstrap_cmd }
 
     it 'expect to remove previous repo, build new and return path to it' do
-      expect(described_class).to receive(:destroy)
-      expect(SupportEngine::Shell).to receive(:call).with(shell_args).and_return('test')
+      allow(described_class).to receive(:destroy)
+      allow(SupportEngine::Shell).to receive(:call).with(shell_args).and_return('test')
       expect(bootstrap).to eq('test')
+      expect(described_class).to have_received(:destroy)
+      expect(SupportEngine::Shell).to have_received(:call).with(shell_args)
     end
   end
 end
diff --git a/spec/lib/support_engine/git/repo_builder/master_mirror_spec.rb b/spec/lib/support_engine/git/repo_builder/master_mirror_spec.rb
index 179c139..9f70dd2 100644
--- a/spec/lib/support_engine/git/repo_builder/master_mirror_spec.rb
+++ b/spec/lib/support_engine/git/repo_builder/master_mirror_spec.rb
@@ -12,9 +12,11 @@
     end
 
     it 'expect to remove previous repo, clone mirror to a new one and return clone path' do
-      expect(described_class).to receive(:destroy)
-      expect(SupportEngine::Git).to receive(:clone_mirror).with(*clone_args).and_return('test')
+      allow(described_class).to receive(:destroy)
+      allow(SupportEngine::Git).to receive(:clone_mirror).with(*clone_args).and_return('test')
       expect(bootstrap).to eq('test')
+      expect(described_class).to have_received(:destroy)
+      expect(SupportEngine::Git).to have_received(:clone_mirror).with(*clone_args)
     end
   end
 end
diff --git a/spec/lib/support_engine/git/repo_builder/master_multiple_committers_spec.rb b/spec/lib/support_engine/git/repo_builder/master_multiple_committers_spec.rb
index 694f050..aa784ca 100644
--- a/spec/lib/support_engine/git/repo_builder/master_multiple_committers_spec.rb
+++ b/spec/lib/support_engine/git/repo_builder/master_multiple_committers_spec.rb
@@ -1,15 +1,17 @@
 # frozen_string_literal: true
 
 RSpec.describe_current do
-  describe 'BOOTSTRAP_CMD' do
+  describe '.bootstrap_cmd' do
     subject(:bootstrap) { described_class.bootstrap }
 
-    let(:shell_args) { described_class::BOOTSTRAP_CMD }
+    let(:shell_args) { described_class.bootstrap_cmd }
 
     it 'expect to remove previous repo, build new and return path to it' do
-      expect(described_class).to receive(:destroy)
-      expect(SupportEngine::Shell).to receive(:call).with(shell_args).and_return('test')
+      allow(described_class).to receive(:destroy)
+      allow(SupportEngine::Shell).to receive(:call).with(shell_args).and_return('test')
       expect(bootstrap).to eq('test')
+      expect(described_class).to have_received(:destroy)
+      expect(SupportEngine::Shell).to have_received(:call).with(shell_args)
     end
   end
 end
diff --git a/spec/lib/support_engine/git/repo_builder/master_only_spec.rb b/spec/lib/support_engine/git/repo_builder/master_only_spec.rb
index 694f050..aa784ca 100644
--- a/spec/lib/support_engine/git/repo_builder/master_only_spec.rb
+++ b/spec/lib/support_engine/git/repo_builder/master_only_spec.rb
@@ -1,15 +1,17 @@
 # frozen_string_literal: true
 
 RSpec.describe_current do
-  describe 'BOOTSTRAP_CMD' do
+  describe '.bootstrap_cmd' do
     subject(:bootstrap) { described_class.bootstrap }
 
-    let(:shell_args) { described_class::BOOTSTRAP_CMD }
+    let(:shell_args) { described_class.bootstrap_cmd }
 
     it 'expect to remove previous repo, build new and return path to it' do
-      expect(described_class).to receive(:destroy)
-      expect(SupportEngine::Shell).to receive(:call).with(shell_args).and_return('test')
+      allow(described_class).to receive(:destroy)
+      allow(SupportEngine::Shell).to receive(:call).with(shell_args).and_return('test')
       expect(bootstrap).to eq('test')
+      expect(described_class).to have_received(:destroy)
+      expect(SupportEngine::Shell).to have_received(:call).with(shell_args)
     end
   end
 end
diff --git a/spec/lib/support_engine/git/repo_builder/master_spec.rb b/spec/lib/support_engine/git/repo_builder/master_spec.rb
index 694f050..aa784ca 100644
--- a/spec/lib/support_engine/git/repo_builder/master_spec.rb
+++ b/spec/lib/support_engine/git/repo_builder/master_spec.rb
@@ -1,15 +1,17 @@
 # frozen_string_literal: true
 
 RSpec.describe_current do
-  describe 'BOOTSTRAP_CMD' do
+  describe '.bootstrap_cmd' do
     subject(:bootstrap) { described_class.bootstrap }
 
-    let(:shell_args) { described_class::BOOTSTRAP_CMD }
+    let(:shell_args) { described_class.bootstrap_cmd }
 
     it 'expect to remove previous repo, build new and return path to it' do
-      expect(described_class).to receive(:destroy)
-      expect(SupportEngine::Shell).to receive(:call).with(shell_args).and_return('test')
+      allow(described_class).to receive(:destroy)
+      allow(SupportEngine::Shell).to receive(:call).with(shell_args).and_return('test')
       expect(bootstrap).to eq('test')
+      expect(described_class).to have_received(:destroy)
+      expect(SupportEngine::Shell).to have_received(:call).with(shell_args)
     end
   end
 end
diff --git a/spec/lib/support_engine/git/repo_builder/master_with_big_branch60_spec.rb b/spec/lib/support_engine/git/repo_builder/master_with_big_branch60_spec.rb
index d1a594f..887eff6 100644
--- a/spec/lib/support_engine/git/repo_builder/master_with_big_branch60_spec.rb
+++ b/spec/lib/support_engine/git/repo_builder/master_with_big_branch60_spec.rb
@@ -1,7 +1,7 @@
 # frozen_string_literal: true
 
 RSpec.describe_current do
-  describe 'BOOTSTRAP_CMD' do
+  describe '.bootstrap_cmd' do
     subject(:bootstrap) { described_class.bootstrap }
 
     after { described_class.destroy }
diff --git a/spec/lib/support_engine/git/repo_builder/master_with_big_branch_mirror_spec.rb b/spec/lib/support_engine/git/repo_builder/master_with_big_branch_mirror_spec.rb
index 463cb75..bbb349e 100644
--- a/spec/lib/support_engine/git/repo_builder/master_with_big_branch_mirror_spec.rb
+++ b/spec/lib/support_engine/git/repo_builder/master_with_big_branch_mirror_spec.rb
@@ -12,9 +12,11 @@
     end
 
     it 'expect to remove previous repo, clone mirror to a new one and return clone path' do
-      expect(described_class).to receive(:destroy)
-      expect(SupportEngine::Git).to receive(:clone_mirror).with(*clone_args).and_return('test')
+      allow(described_class).to receive(:destroy)
+      allow(SupportEngine::Git).to receive(:clone_mirror).with(*clone_args).and_return('test')
       expect(bootstrap).to eq('test')
+      expect(described_class).to have_received(:destroy)
+      expect(SupportEngine::Git).to have_received(:clone_mirror).with(*clone_args)
     end
   end
 end
diff --git a/spec/lib/support_engine/git/repo_builder/master_with_big_branch_spec.rb b/spec/lib/support_engine/git/repo_builder/master_with_big_branch_spec.rb
index d1a594f..887eff6 100644
--- a/spec/lib/support_engine/git/repo_builder/master_with_big_branch_spec.rb
+++ b/spec/lib/support_engine/git/repo_builder/master_with_big_branch_spec.rb
@@ -1,7 +1,7 @@
 # frozen_string_literal: true
 
 RSpec.describe_current do
-  describe 'BOOTSTRAP_CMD' do
+  describe '.bootstrap_cmd' do
     subject(:bootstrap) { described_class.bootstrap }
 
     after { described_class.destroy }
diff --git a/spec/lib/support_engine/git/repo_builder/master_with_history_spec.rb b/spec/lib/support_engine/git/repo_builder/master_with_history_spec.rb
index d1a594f..887eff6 100644
--- a/spec/lib/support_engine/git/repo_builder/master_with_history_spec.rb
+++ b/spec/lib/support_engine/git/repo_builder/master_with_history_spec.rb
@@ -1,7 +1,7 @@
 # frozen_string_literal: true
 
 RSpec.describe_current do
-  describe 'BOOTSTRAP_CMD' do
+  describe '.bootstrap_cmd' do
     subject(:bootstrap) { described_class.bootstrap }
 
     after { described_class.destroy }
diff --git a/spec/lib/support_engine/git/repo_builder/master_with_weird_branch_spec.rb b/spec/lib/support_engine/git/repo_builder/master_with_weird_branch_spec.rb
index d1a594f..887eff6 100644
--- a/spec/lib/support_engine/git/repo_builder/master_with_weird_branch_spec.rb
+++ b/spec/lib/support_engine/git/repo_builder/master_with_weird_branch_spec.rb
@@ -1,7 +1,7 @@
 # frozen_string_literal: true
 
 RSpec.describe_current do
-  describe 'BOOTSTRAP_CMD' do
+  describe '.bootstrap_cmd' do
     subject(:bootstrap) { described_class.bootstrap }
 
     after { described_class.destroy }
diff --git a/spec/lib/support_engine/git/repo_builder/no_master_mirror_spec.rb b/spec/lib/support_engine/git/repo_builder/no_master_mirror_spec.rb
index 6f29577..54f2347 100644
--- a/spec/lib/support_engine/git/repo_builder/no_master_mirror_spec.rb
+++ b/spec/lib/support_engine/git/repo_builder/no_master_mirror_spec.rb
@@ -12,9 +12,11 @@
     end
 
     it 'expect to remove previous repo, clone mirror to a new one and return clone path' do
-      expect(described_class).to receive(:destroy)
-      expect(SupportEngine::Git).to receive(:clone_mirror).with(*clone_args).and_return('test')
+      allow(described_class).to receive(:destroy)
+      allow(SupportEngine::Git).to receive(:clone_mirror).with(*clone_args).and_return('test')
       expect(bootstrap).to eq('test')
+      expect(described_class).to have_received(:destroy)
+      expect(SupportEngine::Git).to have_received(:clone_mirror).with(*clone_args)
     end
   end
 end
diff --git a/spec/lib/support_engine/git/repo_builder/no_master_spec.rb b/spec/lib/support_engine/git/repo_builder/no_master_spec.rb
index 694f050..aa784ca 100644
--- a/spec/lib/support_engine/git/repo_builder/no_master_spec.rb
+++ b/spec/lib/support_engine/git/repo_builder/no_master_spec.rb
@@ -1,15 +1,17 @@
 # frozen_string_literal: true
 
 RSpec.describe_current do
-  describe 'BOOTSTRAP_CMD' do
+  describe '.bootstrap_cmd' do
     subject(:bootstrap) { described_class.bootstrap }
 
-    let(:shell_args) { described_class::BOOTSTRAP_CMD }
+    let(:shell_args) { described_class.bootstrap_cmd }
 
     it 'expect to remove previous repo, build new and return path to it' do
-      expect(described_class).to receive(:destroy)
-      expect(SupportEngine::Shell).to receive(:call).with(shell_args).and_return('test')
+      allow(described_class).to receive(:destroy)
+      allow(SupportEngine::Shell).to receive(:call).with(shell_args).and_return('test')
       expect(bootstrap).to eq('test')
+      expect(described_class).to have_received(:destroy)
+      expect(SupportEngine::Shell).to have_received(:call).with(shell_args)
     end
   end
 end
diff --git a/spec/lib/support_engine/git/repo_builder/outdated_gems_spec.rb b/spec/lib/support_engine/git/repo_builder/outdated_gems_spec.rb
index 694f050..aa784ca 100644
--- a/spec/lib/support_engine/git/repo_builder/outdated_gems_spec.rb
+++ b/spec/lib/support_engine/git/repo_builder/outdated_gems_spec.rb
@@ -1,15 +1,17 @@
 # frozen_string_literal: true
 
 RSpec.describe_current do
-  describe 'BOOTSTRAP_CMD' do
+  describe '.bootstrap_cmd' do
     subject(:bootstrap) { described_class.bootstrap }
 
-    let(:shell_args) { described_class::BOOTSTRAP_CMD }
+    let(:shell_args) { described_class.bootstrap_cmd }
 
     it 'expect to remove previous repo, build new and return path to it' do
-      expect(described_class).to receive(:destroy)
-      expect(SupportEngine::Shell).to receive(:call).with(shell_args).and_return('test')
+      allow(described_class).to receive(:destroy)
+      allow(SupportEngine::Shell).to receive(:call).with(shell_args).and_return('test')
       expect(bootstrap).to eq('test')
+      expect(described_class).to have_received(:destroy)
+      expect(SupportEngine::Shell).to have_received(:call).with(shell_args)
     end
   end
 end
diff --git a/spec/lib/support_engine/git/repo_builder/outdated_gems_strict_spec.rb b/spec/lib/support_engine/git/repo_builder/outdated_gems_strict_spec.rb
index 694f050..aa784ca 100644
--- a/spec/lib/support_engine/git/repo_builder/outdated_gems_strict_spec.rb
+++ b/spec/lib/support_engine/git/repo_builder/outdated_gems_strict_spec.rb
@@ -1,15 +1,17 @@
 # frozen_string_literal: true
 
 RSpec.describe_current do
-  describe 'BOOTSTRAP_CMD' do
+  describe '.bootstrap_cmd' do
     subject(:bootstrap) { described_class.bootstrap }
 
-    let(:shell_args) { described_class::BOOTSTRAP_CMD }
+    let(:shell_args) { described_class.bootstrap_cmd }
 
     it 'expect to remove previous repo, build new and return path to it' do
-      expect(described_class).to receive(:destroy)
-      expect(SupportEngine::Shell).to receive(:call).with(shell_args).and_return('test')
+      allow(described_class).to receive(:destroy)
+      allow(SupportEngine::Shell).to receive(:call).with(shell_args).and_return('test')
       expect(bootstrap).to eq('test')
+      expect(described_class).to have_received(:destroy)
+      expect(SupportEngine::Shell).to have_received(:call).with(shell_args)
     end
   end
 end
diff --git a/spec/lib/support_engine/git/repo_builder/private_gem_spec.rb b/spec/lib/support_engine/git/repo_builder/private_gem_spec.rb
index d1a594f..887eff6 100644
--- a/spec/lib/support_engine/git/repo_builder/private_gem_spec.rb
+++ b/spec/lib/support_engine/git/repo_builder/private_gem_spec.rb
@@ -1,7 +1,7 @@
 # frozen_string_literal: true
 
 RSpec.describe_current do
-  describe 'BOOTSTRAP_CMD' do
+  describe '.bootstrap_cmd' do
     subject(:bootstrap) { described_class.bootstrap }
 
     after { described_class.destroy }
diff --git a/spec/lib/support_engine/git/repo_builder/yarn_spec.rb b/spec/lib/support_engine/git/repo_builder/yarn_spec.rb
index 694f050..aa784ca 100644
--- a/spec/lib/support_engine/git/repo_builder/yarn_spec.rb
+++ b/spec/lib/support_engine/git/repo_builder/yarn_spec.rb
@@ -1,15 +1,17 @@
 # frozen_string_literal: true
 
 RSpec.describe_current do
-  describe 'BOOTSTRAP_CMD' do
+  describe '.bootstrap_cmd' do
     subject(:bootstrap) { described_class.bootstrap }
 
-    let(:shell_args) { described_class::BOOTSTRAP_CMD }
+    let(:shell_args) { described_class.bootstrap_cmd }
 
     it 'expect to remove previous repo, build new and return path to it' do
-      expect(described_class).to receive(:destroy)
-      expect(SupportEngine::Shell).to receive(:call).with(shell_args).and_return('test')
+      allow(described_class).to receive(:destroy)
+      allow(SupportEngine::Shell).to receive(:call).with(shell_args).and_return('test')
       expect(bootstrap).to eq('test')
+      expect(described_class).to have_received(:destroy)
+      expect(SupportEngine::Shell).to have_received(:call).with(shell_args)
     end
   end
 end
diff --git a/spec/lib/support_engine/git/repo_builder_spec.rb b/spec/lib/support_engine/git/repo_builder_spec.rb
index 4daae78..d405544 100644
--- a/spec/lib/support_engine/git/repo_builder_spec.rb
+++ b/spec/lib/support_engine/git/repo_builder_spec.rb
@@ -8,9 +8,11 @@
     let(:versions) { [version] }
 
     it 'expect to take all the versions and bootstrap all of them' do
-      expect(described_class).to receive(:versions) { versions }
-      expect(version).to receive(:bootstrap)
+      allow(described_class).to receive(:versions).and_return(versions)
+      allow(version).to receive(:bootstrap)
       bootstrap
+      expect(described_class).to have_received(:versions)
+      expect(version).to have_received(:bootstrap)
     end
   end
 
@@ -21,9 +23,11 @@
     let(:versions) { [version] }
 
     it 'expect to take all the versions and destroy all of them' do
-      expect(described_class).to receive(:versions) { versions }
-      expect(version).to receive(:destroy)
+      allow(described_class).to receive(:versions).and_return(versions)
+      allow(version).to receive(:destroy)
       destroy
+      expect(described_class).to have_received(:versions)
+      expect(version).to have_received(:destroy)
     end
   end
 
diff --git a/spec/lib/support_engine/git/status_spec.rb b/spec/lib/support_engine/git/status_spec.rb
index 662e615..46ff1f6 100644
--- a/spec/lib/support_engine/git/status_spec.rb
+++ b/spec/lib/support_engine/git/status_spec.rb
@@ -21,32 +21,32 @@
     end
 
     context 'when some files were introduced' do
-      let(:introduced_file_name1) { rand.to_s }
-      let(:introduced_file_name2) { rand.to_s }
+      let(:first_introduced_file) { rand.to_s }
+      let(:second_introduced_file) { rand.to_s }
 
       before do
-        `echo change >> #{File.join(path, introduced_file_name1)}`
-        `echo change >> #{File.join(path, introduced_file_name2)}`
+        `echo change >> #{File.join(path, first_introduced_file)}`
+        `echo change >> #{File.join(path, second_introduced_file)}`
       end
 
       it { expect(introduced.size).to eq 2 }
-      it { is_expected.to include introduced_file_name1 }
-      it { is_expected.to include introduced_file_name2 }
+      it { is_expected.to include first_introduced_file }
+      it { is_expected.to include second_introduced_file }
     end
 
     context 'when some files were introduced and changed' do
-      let(:introduced_file_name1) { rand.to_s }
-      let(:introduced_file_name2) { rand.to_s }
+      let(:first_introduced_file) { rand.to_s }
+      let(:second_introduced_file) { rand.to_s }
 
       before do
         `echo change >> #{File.join(path, 'master.rb')}`
-        `echo change >> #{File.join(path, introduced_file_name1)}`
-        `echo change >> #{File.join(path, introduced_file_name2)}`
+        `echo change >> #{File.join(path, first_introduced_file)}`
+        `echo change >> #{File.join(path, second_introduced_file)}`
       end
 
       it { expect(introduced.size).to eq 2 }
-      it { is_expected.to include introduced_file_name1 }
-      it { is_expected.to include introduced_file_name2 }
+      it { is_expected.to include first_introduced_file }
+      it { is_expected.to include second_introduced_file }
     end
   end
 end
diff --git a/spec/lib/support_engine/git_spec.rb b/spec/lib/support_engine/git_spec.rb
index ecde764..b0d9c84 100644
--- a/spec/lib/support_engine/git_spec.rb
+++ b/spec/lib/support_engine/git_spec.rb
@@ -133,12 +133,12 @@
       let(:ref) { '7987d360dc73ac64ead4a26f8a451822e37788f5' }
       let(:message) do
         "Note: checking out '7987d360dc73ac64ead4a26f8a451822e37788f5'.\n\n" \
-        "You are in 'detached HEAD' state. You can look around, make experimental\n" \
-        "changes and commit them, and you can discard any commits you make in this\n" \
-        "state without impacting any branches by performing another checkout.\n\n" \
-        "If you want to create a new branch to retain commits you create, you may\n" \
-        "do so (now or later) by using -b with the checkout command again. Example:\n\n  " \
-        "git checkout -b <new-branch-name>\n\nHEAD is now at 7987d36... master commit"
+          "You are in 'detached HEAD' state. You can look around, make experimental\n" \
+          "changes and commit them, and you can discard any commits you make in this\n" \
+          "state without impacting any branches by performing another checkout.\n\n" \
+          "If you want to create a new branch to retain commits you create, you may\n" \
+          "do so (now or later) by using -b with the checkout command again. Example:\n\n  " \
+          "git checkout -b <new-branch-name>\n\nHEAD is now at 7987d36... master commit"
       end
 
       it { is_expected.to be true }
diff --git a/spec/lib/support_engine/rspec_locator_spec.rb b/spec/lib/support_engine/rspec_locator_spec.rb
index 64d9fa3..1829cf5 100644
--- a/spec/lib/support_engine/rspec_locator_spec.rb
+++ b/spec/lib/support_engine/rspec_locator_spec.rb
@@ -1,5 +1,7 @@
 # frozen_string_literal: true
 
+# rubocop:disable RSpec/SpecFilePathFormat
 RSpec.describe SupportEngine::RSpecLocator do
-  pending
+  pending 'Not yet implemented'
 end
+# rubocop:enable RSpec/SpecFilePathFormat
diff --git a/spec/lib/support_engine/shell/utf8_spec.rb b/spec/lib/support_engine/shell/utf8_spec.rb
index 17114d9..441151f 100644
--- a/spec/lib/support_engine/shell/utf8_spec.rb
+++ b/spec/lib/support_engine/shell/utf8_spec.rb
@@ -9,12 +9,13 @@
     let(:command_with_options) { 'ls' }
     let(:options) { { raise_on_invalid_exit: true } }
 
-    after { shell_result }
-
     it 'expect to run shell and encode' do
-      expect(SupportEngine::Shell).to receive(:call)
+      allow(SupportEngine::Shell).to receive(:call)
         .with(command_with_options, options).and_return(true)
-      expect(described_class).to receive(:encode).with(true)
+      allow(described_class).to receive(:encode).with(true)
+      shell_result
+      expect(SupportEngine::Shell).to have_received(:call).with(command_with_options, options)
+      expect(described_class).to have_received(:encode).with(true)
     end
   end
 
@@ -28,11 +29,12 @@
     let(:options) { { raise_on_invalid_exit: true } }
     let(:shell_args) { [path, command_with_options, options] }
 
-    after { shell_result }
-
     it 'expect to call shell in path and encode' do
-      expect(SupportEngine::Shell).to receive(:call_in_path).with(*shell_args).and_return(true)
-      expect(described_class).to receive(:encode).with(true)
+      allow(SupportEngine::Shell).to receive(:call_in_path).with(*shell_args).and_return(true)
+      allow(described_class).to receive(:encode).with(true)
+      shell_result
+      expect(SupportEngine::Shell).to have_received(:call_in_path).with(*shell_args)
+      expect(described_class).to have_received(:encode).with(true)
     end
   end
 
diff --git a/spec/lib/support_engine/shell/yarn_spec.rb b/spec/lib/support_engine/shell/yarn_spec.rb
index 31933b2..f9597b0 100644
--- a/spec/lib/support_engine/shell/yarn_spec.rb
+++ b/spec/lib/support_engine/shell/yarn_spec.rb
@@ -9,13 +9,14 @@
     let(:args) do
       [
         "yarn run --silent #{command} #{options}",
-        raise_on_invalid_exit: true
+        { raise_on_invalid_exit: true }
       ]
     end
 
     it 'expect to run yarn in shell' do
-      expect(SupportEngine::Shell::Utf8).to receive(:call).with(*args)
+      allow(SupportEngine::Shell::Utf8).to receive(:call).with(*args)
       shell_result
+      expect(SupportEngine::Shell::Utf8).to have_received(:call).with(*args)
     end
   end
 
diff --git a/spec/lib/support_engine/shell_spec.rb b/spec/lib/support_engine/shell_spec.rb
index 88215a0..8d44c6c 100644
--- a/spec/lib/support_engine/shell_spec.rb
+++ b/spec/lib/support_engine/shell_spec.rb
@@ -5,7 +5,7 @@
     subject(:shell_result) do
       described_class.call(
         command_with_options,
-        raise_on_invalid_exit: raise_on_invalid_exit
+        raise_on_invalid_exit:
       )
     end
 
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index 516ffd4..2a9a094 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -15,8 +15,10 @@
 require 'support_engine/git/repo_builder'
 require 'support_engine/rspec_locator'
 
+# rubocop:disable Rails/TimeZoneAssignment
 # Set default timezone
 Time.zone = 'UTC'
+# rubocop:enable Rails/TimeZoneAssignment
 
 SimpleCov.minimum_coverage 98.5