diff --git a/.github/workflows/alpine.yml b/.github/workflows/alpine.yml
index 03b399ec..f32ba0f2 100644
--- a/.github/workflows/alpine.yml
+++ b/.github/workflows/alpine.yml
@@ -60,7 +60,7 @@ concurrency:
   cancel-in-progress: true
 
 env:
-  CACHE_VER: 17
+  CACHE_VER: 19
   TZ: "Etc/UTC"
   VERBOSE: no
 
diff --git a/.github/workflows/gem-test-and-release.yml b/.github/workflows/gem-test-and-release.yml
index 6af995f5..e4f6cf3c 100644
--- a/.github/workflows/gem-test-and-release.yml
+++ b/.github/workflows/gem-test-and-release.yml
@@ -49,7 +49,7 @@ concurrency:
   cancel-in-progress: true
 
 env:
-  CACHE_VER: 16
+  CACHE_VER: 19
   DEBIAN_FRONTEND: "noninteractive"
   TZ: "Etc/UTC"
 # show cmake output
diff --git a/.github/workflows/macos.yml b/.github/workflows/macos.yml
index d0e9a670..ae361d4b 100644
--- a/.github/workflows/macos.yml
+++ b/.github/workflows/macos.yml
@@ -58,7 +58,7 @@ concurrency:
   cancel-in-progress: true
 
 env:
-  CACHE_VER: 17
+  CACHE_VER: 19
   VERBOSE: no
 
 jobs:
diff --git a/.github/workflows/ubuntu.yml b/.github/workflows/ubuntu.yml
index 420afb19..e8d2f751 100644
--- a/.github/workflows/ubuntu.yml
+++ b/.github/workflows/ubuntu.yml
@@ -60,7 +60,7 @@ concurrency:
   cancel-in-progress: true
 
 env:
-  CACHE_VER: 17
+  CACHE_VER: 19
   DEBIAN_FRONTEND: "noninteractive"
   TZ: "Etc/UTC"
 # show cmake output (yes/no)
diff --git a/.github/workflows/windows-msys.yml b/.github/workflows/windows-msys.yml
index 80f13ba2..9a9ab71c 100644
--- a/.github/workflows/windows-msys.yml
+++ b/.github/workflows/windows-msys.yml
@@ -60,7 +60,7 @@ concurrency:
   cancel-in-progress: true
 
 env:
-  CACHE_VER: 17
+  CACHE_VER: 19
   VERBOSE: no
 
 jobs:
diff --git a/CMakeLists.txt b/CMakeLists.txt
index d80ae4e7..0b6d4be7 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -431,7 +431,7 @@ if (${SETUP_MODE})
 
   add_dependencies(tebako-fs packaged_filesystem)
 
-  add_custom_target(tebako COMMAND ruby ${EXE}/tebako-packager finalize ${OSTYPE_TXT} ${RUBY_SOURCE_DIR} ${APP_NAME} ${RUBY_VER} ${DEPS_BIN_DIR}/patchelf ${WITH_PATCHELF})
+  add_custom_target(tebako COMMAND ruby ${EXE}/tebako-packager finalize ${RUBY_SOURCE_DIR} ${APP_NAME} ${RUBY_VER} ${DEPS_BIN_DIR}/patchelf ${WITH_PATCHELF})
   add_dependencies(tebako setup tebako-fs)
 
 endif(${SETUP_MODE})
diff --git a/exe/tebako-packager b/exe/tebako-packager
index af0d228c..a1ec6cb8 100755
--- a/exe/tebako-packager
+++ b/exe/tebako-packager
@@ -70,19 +70,18 @@ begin
 
   when "finalize"
     #       ARGV[0] -- command
-    #       ARGV[1] -- OSTYPE
-    #       ARGV[2] -- RUBY_SOURCE_DIR
-    #       ARGV[3] -- APP_NAME
-    #       ARGV[4] -- RUBY_VER
-    #       ARGV[5] -- patchelf executable
-    #       ARGV[6] -- WITH_PATHELF
-    unless ARGV.length == 7
+    #       ARGV[1] -- RUBY_SOURCE_DIR
+    #       ARGV[2] -- APP_NAME
+    #       ARGV[3] -- RUBY_VER
+    #       ARGV[4] -- patchelf executable
+    #       ARGV[5] -- WITH_PATHELF
+    unless ARGV.length == 6
       raise Tebako::Error,
-            "tebako-packager finalize command expects 7 arguments, #{ARGV.length} has been provided."
+            "tebako-packager finalize command expects 6 arguments, #{ARGV.length} has been provided."
     end
-    ruby_ver = Tebako::RubyVersion.new(ARGV[4])
-    with_patchelf = ARGV[6].casecmp("ON").zero? || ARGV[6].casecmp("YES").zero?
-    Tebako::Packager.finalize(ARGV[1], ARGV[2], ARGV[3], ruby_ver, with_patchelf ? ARGV[5] : nil)
+    ruby_ver = Tebako::RubyVersion.new(ARGV[3])
+    with_patchelf = ARGV[5].casecmp("ON").zero? || ARGV[5].casecmp("YES").zero?
+    Tebako::Packager.finalize(ARGV[1], ARGV[2], ruby_ver, with_patchelf ? ARGV[4] : nil)
   else
     raise Tebako::Error, "tebako-packager cannot process #{ARGV[0]} command"
   end
diff --git a/lib/tebako/build_helpers.rb b/lib/tebako/build_helpers.rb
index 835e4dc1..80c8801e 100755
--- a/lib/tebako/build_helpers.rb
+++ b/lib/tebako/build_helpers.rb
@@ -32,20 +32,6 @@ module Tebako
   # Ruby build helpers
   module BuildHelpers
     class << self
-      def ncores
-        if RUBY_PLATFORM.include?("darwin")
-          out, st = Open3.capture2e("sysctl", "-n", "hw.ncpu")
-        else
-          out, st = Open3.capture2e("nproc", "--all")
-        end
-
-        if !st.signaled? && st.exitstatus.zero?
-          out.strip.to_i
-        else
-          4
-        end
-      end
-
       def run_with_capture(args)
         args = args.compact
         puts "   ... @ #{args.join(" ")}"
diff --git a/lib/tebako/cli.rb b/lib/tebako/cli.rb
index ff1dcaa0..5f776208 100755
--- a/lib/tebako/cli.rb
+++ b/lib/tebako/cli.rb
@@ -28,6 +28,8 @@
 
 require "digest"
 require "fileutils"
+require "find"
+require "pathname"
 require "open3"
 require "thor"
 require "yaml"
@@ -36,6 +38,7 @@
 require_relative "cli_helpers"
 require_relative "error"
 require_relative "ruby_version"
+require_relative "scenario_manager"
 require_relative "version"
 
 # Tebako - an executable packager
@@ -66,10 +69,11 @@ def clean_ruby
       (om,) = bootstrap(clean: true)
 
       suffix = options["Ruby"].nil? ? "" : "_#{options["Ruby"]}"
-      nmr = "src/_ruby#{suffix}*"
-      nms = "stash#{suffix}*"
-      FileUtils.rm_rf(Dir.glob(File.join(om.deps, nmr)), secure: true)
-      FileUtils.rm_rf(Dir.glob(File.join(om.deps, nms)), secure: true)
+      nmr = Dir.glob(File.join(om.deps, "src", "_ruby#{suffix}*"))
+      nms = Dir.glob(File.join(om.deps, "stash#{suffix}*"))
+
+      FileUtils.rm_rf(nmr + nms, secure: true)
+      extra_win_clean(nmr)
     end
 
     desc "hash", "Print build script hash (ci cache key)"
@@ -147,13 +151,29 @@ def bootstrap(clean: false)
         [options_manager, cache_manager]
       end
 
+      # Ruby extension maker sometimes creates files with 'NUL' name on Windows
+      # This method removes such files
+      def extra_win_clean(nmr)
+        return unless nmr.any? && ScenarioManagerBase.new.msys?
+
+        nmr.each do |path|
+          if File.basename(path) == "NUL"
+            full_path = "//?/#{path}"
+            FileUtils.rm_f(full_path)
+          end
+        end
+        FileUtils.rm_rf(nmr, secure: true)
+      end
+
       def initialize(*args)
         super
         return if args[2][:current_command].name.include?("hash")
 
         puts "Tebako executable packager version #{Tebako::VERSION}"
       end
+    end
 
+    no_commands do
       def options
         original_options = super
         tebafile = original_options["tebafile"].nil? ? DEFAULT_TEBAFILE : original_options["tebafile"]
@@ -164,9 +184,7 @@ def options
           original_options
         end
       end
-    end
 
-    no_commands do
       def source
         c_path = Pathname.new(__FILE__).realpath
         @source ||= File.expand_path("../../..", c_path)
@@ -177,7 +195,10 @@ def validate_press_options
 
         opts = ""
         opts += " '--root'" if options["root"].nil?
-        opts += " '--entry-point'" if options["entry-point"].nil?
+        if options["entry-point"].nil?
+          opts += ", " unless opts.empty?
+          opts += " '--entry-point'"
+        end
         raise Thor::Error, "No value provided for required options #{opts}" unless opts.empty?
       end
     end
diff --git a/lib/tebako/cli_helpers.rb b/lib/tebako/cli_helpers.rb
index d3ae05f5..ec40e5dd 100644
--- a/lib/tebako/cli_helpers.rb
+++ b/lib/tebako/cli_helpers.rb
@@ -82,7 +82,7 @@ def do_press_runtime(options_manager, scenario_manager)
       return unless %w[both runtime bundle].include?(options_manager.mode)
 
       generate_files(options_manager, scenario_manager)
-      merged_env = ENV.to_h.merge(options_manager.b_env)
+      merged_env = ENV.to_h.merge(scenario_manager.b_env)
       Tebako.packaging_error(103) unless system(merged_env, press_cfg_cmd(options_manager))
       Tebako.packaging_error(104) unless system(merged_env, press_build_cmd(options_manager))
     end
@@ -90,7 +90,7 @@ def do_press_runtime(options_manager, scenario_manager)
     def do_setup(options_manager)
       puts "Setting up tebako packaging environment"
 
-      merged_env = ENV.to_h.merge(options_manager.b_env)
+      merged_env = ENV.to_h.merge(Tebako::ScenarioManagerBase.new.b_env)
       Tebako.packaging_error(101) unless system(merged_env, setup_cfg_cmd(options_manager))
       Tebako.packaging_error(102) unless system(merged_env, setup_build_cmd(options_manager))
     end
diff --git a/lib/tebako/deploy_helper.rb b/lib/tebako/deploy_helper.rb
index 0ea4769e..38e0736c 100644
--- a/lib/tebako/deploy_helper.rb
+++ b/lib/tebako/deploy_helper.rb
@@ -48,7 +48,6 @@ def initialize(fs_root, fs_entrance, target_dir, pre_dir)
       @target_dir = target_dir
       @pre_dir = pre_dir
       @verbose = %w[yes true].include?(ENV.fetch("VERBOSE", nil))
-      @ncores = BuildHelpers.ncores
     end
 
     attr_reader :gem_home
@@ -162,7 +161,7 @@ def collect_and_deploy_gem_and_gemfile(gemspec)
       Dir.chdir(@pre_dir) do
         bundle_config
         puts "   *** It may take a long time for a big project. It takes REALLY long time on Windows ***"
-        BuildHelpers.run_with_capture_v([@bundler_command, bundler_reference, "install", "--jobs=#{@ncores}"])
+        BuildHelpers.run_with_capture_v([@bundler_command, bundler_reference, "install", "--jobs=#{ncores}"])
         BuildHelpers.run_with_capture_v([@bundler_command, bundler_reference, "exec", @gem_command, "build", gemspec])
         install_all_gems_or_fail
       end
@@ -222,7 +221,7 @@ def deploy_gemfile
       Dir.chdir(@tld) do
         bundle_config
         puts "   *** It may take a long time for a big project. It takes REALLY long time on Windows ***"
-        BuildHelpers.run_with_capture_v([@bundler_command, bundler_reference, "install", "--jobs=#{@ncores}"])
+        BuildHelpers.run_with_capture_v([@bundler_command, bundler_reference, "install", "--jobs=#{ncores}"])
       end
 
       check_entry_point("local")
diff --git a/lib/tebako/options_manager.rb b/lib/tebako/options_manager.rb
index 3b587ba2..092aad64 100644
--- a/lib/tebako/options_manager.rb
+++ b/lib/tebako/options_manager.rb
@@ -44,19 +44,11 @@ def initialize(options)
       @options = options
       @rv = Tebako::RubyVersion.new(@options["Ruby"])
       @ruby_ver, @ruby_hash = @rv.extend_ruby_version
+      @scmb = ScenarioManagerBase.new
     end
 
     attr_reader :ruby_ver, :rv
 
-    def b_env
-      u_flags = if RbConfig::CONFIG["host_os"] =~ /darwin/
-                  "-DTARGET_OS_SIMULATOR=0 -DTARGET_OS_IPHONE=0  #{ENV.fetch("CXXFLAGS", nil)}"
-                else
-                  ENV.fetch("CXXFLAGS", nil)
-                end
-      @b_env ||= { "CXXFLAGS" => u_flags }
-    end
-
     def cfg_options
       ## {v_parts[3]} may be something like rc1 that won't work with CMake
       v_parts = Tebako::VERSION.split(".")
@@ -64,7 +56,7 @@ def cfg_options
       # So we have to use \"xxx\"
       @cfg_options ||=
         "-DCMAKE_BUILD_TYPE=Release -DRUBY_VER:STRING=\"#{@ruby_ver}\" -DRUBY_HASH:STRING=\"#{@ruby_hash}\" " \
-        "-DDEPS:STRING=\"#{deps}\" -G \"#{m_files}\" -B \"#{output_folder}\" -S \"#{source}\" " \
+        "-DDEPS:STRING=\"#{deps}\" -G \"#{@scmb.m_files}\" -B \"#{output_folder}\" -S \"#{source}\" " \
         "#{remove_glibc_private} -DTEBAKO_VERSION:STRING=\"#{v_parts[0]}.#{v_parts[1]}.#{v_parts[2]}\""
     end
 
@@ -127,7 +119,7 @@ def deps_lib_dir
 
     def fs_current
       fs_current = Dir.pwd
-      if RUBY_PLATFORM =~ /msys|mingw|cygwin/
+      if @scmb.msys?
         fs_current, cygpath_res = Open3.capture2e("cygpath", "-w", fs_current)
         Tebako.packaging_error(101) unless cygpath_res.success?
         fs_current.strip!
@@ -158,20 +150,6 @@ def mode
       @mode ||= @options["mode"].nil? ? "bundle" : @options["mode"]
     end
 
-    def m_files
-      # [TODO]
-      # Ninja generates incorrect script for tebako press target -- gets lost in a chain custom targets
-      # Using makefiles has negative performance impact so it needs to be fixed
-      @m_files ||= case RUBY_PLATFORM
-                   when /linux/, /darwin/
-                     "Unix Makefiles"
-                   when /msys|mingw|cygwin/
-                     "MinGW Makefiles"
-                   else
-                     raise Tebako::Error.new("#{RUBY_PLATFORM} is not supported.", 112)
-                   end
-    end
-
     def output_folder
       @output_folder ||= File.join(prefix, "o")
     end
diff --git a/lib/tebako/packager.rb b/lib/tebako/packager.rb
index 12401fd9..b8a1ce99 100644
--- a/lib/tebako/packager.rb
+++ b/lib/tebako/packager.rb
@@ -35,7 +35,7 @@
 require_relative "stripper"
 require_relative "packager/pass1_patch"
 require_relative "packager/pass1a_patch"
-require_relative "packager/pass2"
+require_relative "packager/pass2_patch"
 require_relative "packager/patch_helpers"
 
 # Tebako - an executable packager
@@ -93,15 +93,16 @@ def do_patch(patch_map, root)
         patch_map.each { |fname, mapping| PatchHelpers.patch_file("#{root}/#{fname}", mapping) }
       end
 
-      def finalize(os_type, src_dir, app_name, ruby_ver, patchelf)
+      def finalize(src_dir, app_name, ruby_ver, patchelf)
         puts "-- Running finalize script"
 
         RubyBuilder.new(ruby_ver, src_dir).target_build
-        exe_suffix = Packager::PatchHelpers.exe_suffix(os_type)
+        exe_suffix = ScenarioManagerBase.new.exe_suffix
         src_name = File.join(src_dir, "ruby#{exe_suffix}")
         patchelf(src_name, patchelf)
         package_name = "#{app_name}#{exe_suffix}"
-        strip_or_copy(os_type, src_name, package_name)
+        # strip_or_copy(os_type, src_name, package_name)
+        Tebako::Stripper.strip_file(src_name, package_name)
         puts "Created tebako package at \"#{package_name}\""
       end
 
@@ -149,7 +150,8 @@ def pass1a(ruby_source_dir)
       def pass2(ostype, ruby_source_dir, deps_lib_dir, ruby_ver)
         puts "-- Running pass2 script"
 
-        do_patch(Pass2.get_patch_map(ostype, deps_lib_dir, ruby_ver), ruby_source_dir)
+        patch = Pass2Patch.new(ostype, deps_lib_dir, ruby_ver).patch_map
+        do_patch(patch, ruby_source_dir)
       end
 
       # Stash
@@ -194,15 +196,15 @@ def patchelf(src_name, patchelf)
         BuildHelpers.run_with_capture(params)
       end
 
-      def strip_or_copy(os_type, src_name, package_name)
-        # [TODO] On MSys strip sometimes creates a broken executable
-        # https://github.com/tamatebako/tebako/issues/172
-        if Packager::PatchHelpers.msys?(os_type)
-          FileUtils.cp(src_name, package_name)
-        else
-          Tebako::Stripper.strip_file(src_name, package_name)
-        end
-      end
+      # def strip_or_copy(_os_type, src_name, package_name)
+      # [TODO] On MSys strip sometimes creates a broken executable
+      # https://github.com/tamatebako/tebako/issues/172
+      # if Packager::PatchHelpers.msys?(os_type)
+      # FileUtils.cp(src_name, package_name)
+      # else
+      # Tebako::Stripper.strip_file(src_name, package_name)
+      # end
+      # end
     end
   end
 end
diff --git a/lib/tebako/packager/pass1_patch.rb b/lib/tebako/packager/pass1_patch.rb
index 010ae284..1f75cf00 100644
--- a/lib/tebako/packager/pass1_patch.rb
+++ b/lib/tebako/packager/pass1_patch.rb
@@ -202,23 +202,21 @@ def patch_map
       def gnumakefile_in_patch_p1 # rubocop:disable Metrics/MethodLength
         objext = @ruby_ver.ruby32? ? "$(OBJEXT)" : "@OBJEXT@"
         {
-          "  DLLWRAP += -mno-cygwin" =>
-            "# tebako patched  DLLWRAP += -mno-cygwin",
+          "$(Q) $(DLLWRAP) \\" => GNUMAKEFILE_IN_DLLTOOL_SUBST,
 
           "$(WPROGRAM): $(RUBYW_INSTALL_NAME).res.#{objext}" =>
             "$(WPROGRAM): $(RUBYW_INSTALL_NAME).res.#{objext} $(WINMAINOBJ)  # tebako patched",
 
           "$(MAINOBJ) $(EXTOBJS) $(LIBRUBYARG) $(LIBS) -o $@" =>
+
             "$(WINMAINOBJ) $(EXTOBJS) $(LIBRUBYARG) $(LIBS) -o $@  # tebako patched",
 
-          "--output-exp=$(RUBY_EXP) \\" =>
-           "--output-exp=$(RUBY_EXP) --output-lib=$(LIBRUBY) --output-def=tebako.def \\",
+          "--output-exp=$(RUBY_EXP) \\" => "# tebako patched --output-exp=$(RUBY_EXP) \\",
 
           "--export-all $(LIBRUBY_A) $(LIBS) -o $(PROGRAM)" =>
-            "--export-all $(LIBRUBY_A) $(LIBS) -o program-stub.exe   # tebako patched",
+            "# tebako patched --export-all $(LIBRUBY_A) $(LIBS) -o $(PROGRAM)",
 
-          "@rm -f $(PROGRAM)" =>
-            "@rm -f program-stub.exe   # tebako patched",
+          "@rm -f $(PROGRAM)" => "# tebako patched @rm -f $(PROGRAM)",
 
           "	$(Q) $(LDSHARED) $(DLDFLAGS) $(OBJS) dmyext.o $(SOLIBS) -o $(PROGRAM)" =>
            "# tebako patched  $(Q) $(LDSHARED) $(DLDFLAGS) $(OBJS) dmyext.o $(SOLIBS) -o $(PROGRAM)",
diff --git a/lib/tebako/packager/pass2.rb b/lib/tebako/packager/pass2.rb
deleted file mode 100755
index 8f56b03e..00000000
--- a/lib/tebako/packager/pass2.rb
+++ /dev/null
@@ -1,149 +0,0 @@
-# frozen_string_literal: true
-
-# Copyright (c) 2021-2024 [Ribose Inc](https://www.ribose.com).
-# All rights reserved.
-# This file is a part of tebako
-#
-# Redistribution and use in source and binary forms, with or without
-# modification, are permitted provided that the following conditions
-# are met:
-# 1. Redistributions of source code must retain the above copyright
-#    notice, this list of conditions and the following disclaimer.
-# 2. Redistributions in binary form must reproduce the above copyright
-#    notice, this list of conditions and the following disclaimer in the
-#    documentation and/or other materials provided with the distribution.
-#
-# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-# ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
-# TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
-# PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS
-# BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
-# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
-# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
-# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
-# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
-# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
-# POSSIBILITY OF SUCH DAMAGE.
-
-require_relative "patch_literals"
-require_relative "patch_main"
-require_relative "patch_libraries"
-require_relative "patch_helpers"
-require_relative "patch_buildsystem"
-
-# Tebako - an executable packager
-module Tebako
-  module Packager
-    # Ruby patching definitions (pass2)
-    module Pass2
-      class << self
-        def get_patch_map(ostype, deps_lib_dir, ruby_ver)
-          patch_map = get_patch_map_base(ostype, deps_lib_dir, ruby_ver)
-          patch_map.store("thread_pthread.c", LINUX_MUSL_THREAD_PTHREAD_PATCH) if ostype =~ /linux-musl/
-          if PatchHelpers.msys?(ostype)
-            patch_map.merge!(get_msys_patches(ruby_ver))
-          elsif ruby_ver.ruby3x?
-            patch_map.store("common.mk", COMMON_MK_PATCH)
-          end
-          extend_patch_map_r33(patch_map, ostype, deps_lib_dir, ruby_ver)
-          patch_map.store("prism_compile.c", PRISM_PATCHES) if ruby_ver.ruby34?
-          patch_map
-        end
-
-        private
-
-        include Tebako::Packager::PatchBuildsystem
-        include Tebako::Packager::PatchLiterals
-        def extend_patch_map_r33(patch_map, ostype, deps_lib_dir, ruby_ver)
-          if ruby_ver.ruby33? || PatchHelpers.msys?(ostype)
-            patch_map.store("config.status",
-                            get_config_status_patch(ostype, deps_lib_dir, ruby_ver))
-          end
-          patch_map
-        end
-
-        def get_dir_c_patch(ostype)
-          pattern = PatchHelpers.msys?(ostype) ? "/* define system APIs */" : "#ifdef HAVE_GETATTRLIST"
-          dir_c_patch = PatchHelpers.patch_c_file_pre(pattern)
-          dir_c_patch.merge!(DIR_C_BASE_PATCH)
-          dir_c_patch
-        end
-
-        def get_dln_c_patch(ostype, ruby_ver)
-          pattern = "#ifndef dln_loaderror"
-          # Not using substitutions of dlxxx functions on Windows
-          dln_c_patch = {
-            pattern => "#{PatchHelpers.msys?(ostype) ? C_FILE_SUBST_LESS : C_FILE_SUBST}\n#{pattern}\n"
-          }
-
-          if PatchHelpers.msys?(ostype)
-            patch = ruby_ver.ruby32? ? DLN_C_MSYS_PATCH : DLN_C_MSYS_PATCH_PRE32
-            dln_c_patch.merge!(patch)
-          end
-
-          dln_c_patch
-        end
-
-        def get_io_c_msys_patch(ruby_ver)
-          io_c_msys_patch = ruby_ver.ruby32? ? IO_C_MSYS_PATCH : IO_C_MSYS_PATCH_PRE_32
-          io_c_msys_patch.merge(IO_C_MSYS_BASE_PATCH)
-        end
-
-        def get_io_c_patch(ostype, ruby_ver)
-          io_c_patch = PatchHelpers.patch_c_file_pre("/* define system APIs */")
-          io_c_patch.merge!(get_io_c_msys_patch(ruby_ver)) if PatchHelpers.msys?(ostype)
-          io_c_patch
-        end
-
-        def get_util_c_patch(ruby_ver)
-          if ruby_ver.ruby31?
-            PatchHelpers.patch_c_file_post("#endif /* !HAVE_GNU_QSORT_R */")
-          else
-            PatchHelpers.patch_c_file_pre("#ifndef S_ISDIR")
-          end
-        end
-
-        def get_tool_mkconfig_rb_patch(ostype)
-          subst = PatchHelpers.msys?(ostype) ? TOOL_MKCONFIG_RB_SUBST_MSYS : TOOL_MKCONFIG_RB_SUBST
-          {
-            "    if fast[name]" => subst
-          }
-        end
-
-        def get_msys_patches(ruby_ver)
-          {
-            "cygwin/GNUmakefile.in" => get_gnumakefile_in_patch_p2(ruby_ver),
-            "ruby.c" => RUBY_C_MSYS_PATCHES,
-            "win32/file.c" => WIN32_FILE_C_MSYS_PATCHES,
-            "win32/win32.c" => WIN32_WIN32_C_MSYS_PATCHES
-          }
-        end
-
-        def get_patch_map_base(ostype, deps_lib_dir, ruby_ver)
-          {
-            "template/Makefile.in" => template_makefile_in_patch(ostype, deps_lib_dir, ruby_ver),
-            "tool/mkconfig.rb" => get_tool_mkconfig_rb_patch(ostype),
-            "dir.c" => get_dir_c_patch(ostype),            "dln.c" => get_dln_c_patch(ostype, ruby_ver),
-            "io.c" => get_io_c_patch(ostype, ruby_ver),    "main.c" => PatchMain.get_main_c_patch(ruby_ver),
-            "file.c" => PatchHelpers.patch_c_file_pre("/* define system APIs */"),
-            "util.c" => get_util_c_patch(ruby_ver)
-          }
-        end
-
-        def mlibs_subst(ostype, deps_lib_dir, ruby_ver)
-          yjit_libs = ruby_ver.ruby32only? ? "$(YJIT_LIBS) " : ""
-          {
-            "MAINLIBS = #{yjit_libs}@MAINLIBS@" =>
-              "# -- Start of tebako patch -- \n" \
-              "MAINLIBS = #{yjit_libs}#{PatchLibraries.mlibs(ostype, deps_lib_dir, ruby_ver, true)}\n" \
-              "# -- End of tebako patch -- \n"
-          }
-        end
-
-        def template_makefile_in_patch(ostype, deps_lib_dir, ruby_ver)
-          template_makefile_in_patch_two(ostype, ruby_ver).merge(mlibs_subst(ostype, deps_lib_dir, ruby_ver))
-        end
-      end
-    end
-  end
-end
diff --git a/lib/tebako/packager/pass2_patch.rb b/lib/tebako/packager/pass2_patch.rb
new file mode 100644
index 00000000..108d51db
--- /dev/null
+++ b/lib/tebako/packager/pass2_patch.rb
@@ -0,0 +1,154 @@
+# frozen_string_literal: true
+
+# Copyright (c) 2021-2024 [Ribose Inc](https://www.ribose.com).
+# All rights reserved.
+# This file is a part of tebako
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+# TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+# PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS
+# BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.
+
+require_relative "patch_literals"
+require_relative "patch_main"
+require_relative "patch_libraries"
+require_relative "patch_helpers"
+require_relative "patch_buildsystem"
+
+# Tebako - an executable packager
+module Tebako
+  module Packager
+    # Ruby patching definitions (pass2)
+    class Pass2Patch < Patch
+      def initialize(ostype, deps_lib_dir, ruby_ver)
+        super()
+        @ostype = ostype
+        @scmb = ScenarioManagerBase.new(@ostype)
+        @deps_lib_dir = deps_lib_dir
+        @ruby_ver = ruby_ver
+      end
+
+      def patch_map
+        patch_map = patch_map_base
+        patch_map.store("thread_pthread.c", LINUX_MUSL_THREAD_PTHREAD_PATCH) if @scmb.musl?
+        if @scmb.msys?
+          patch_map.merge!(msys_patches)
+        elsif @ruby_ver.ruby3x?
+          patch_map.store("common.mk", COMMON_MK_PATCH)
+        end
+        extend_patch_map_r33(patch_map)
+        patch_map.store("prism_compile.c", PRISM_PATCHES) if @ruby_ver.ruby34?
+        patch_map
+      end
+
+      private
+
+      include Tebako::Packager::PatchBuildsystem
+      include Tebako::Packager::PatchLiterals
+      def extend_patch_map_r33(patch_map)
+        if @ruby_ver.ruby33? || @scmb.msys?
+          patch_map.store("config.status",
+                          get_config_status_patch(@ostype, @deps_lib_dir, @ruby_ver))
+        end
+        patch_map
+      end
+
+      def dir_c_patch
+        pattern = ScenarioManagerBase.new.msys? ? "/* define system APIs */" : "#ifdef HAVE_GETATTRLIST"
+        patch = PatchHelpers.patch_c_file_pre(pattern)
+        patch.merge!(DIR_C_BASE_PATCH)
+        patch
+      end
+
+      def dln_c_patch
+        pattern = "#ifndef dln_loaderror"
+        # Not using substitutions of dlxxx functions on Windows
+        patch = {
+          pattern => "#{@scmb.msys? ? C_FILE_SUBST_LESS : C_FILE_SUBST}\n#{pattern}\n"
+        }
+
+        if @scmb.msys?
+          patch.merge!(@ruby_ver.ruby32? ? DLN_C_MSYS_PATCH : DLN_C_MSYS_PATCH_PRE32)
+        end
+
+        patch
+      end
+
+      def io_c_msys_patch
+        patch = @ruby_ver.ruby32? ? IO_C_MSYS_PATCH : IO_C_MSYS_PATCH_PRE_32
+        patch.merge(IO_C_MSYS_BASE_PATCH)
+      end
+
+      def io_c_patch
+        patch = PatchHelpers.patch_c_file_pre("/* define system APIs */")
+        patch.merge!(io_c_msys_patch) if @scmb.msys?
+        patch
+      end
+
+      def util_c_patch
+        if @ruby_ver.ruby31?
+          PatchHelpers.patch_c_file_post("#endif /* !HAVE_GNU_QSORT_R */")
+        else
+          PatchHelpers.patch_c_file_pre("#ifndef S_ISDIR")
+        end
+      end
+
+      def tool_mkconfig_rb_patch
+        subst = @scmb.msys? ? TOOL_MKCONFIG_RB_SUBST_MSYS : TOOL_MKCONFIG_RB_SUBST
+        {
+          "    if fast[name]" => subst
+        }
+      end
+
+      def msys_patches
+        {
+          "cygwin/GNUmakefile.in" => get_gnumakefile_in_patch_p2(@ruby_ver),
+          "ruby.c" => RUBY_C_MSYS_PATCHES,
+          "win32/file.c" => WIN32_FILE_C_MSYS_PATCHES,
+          "win32/win32.c" => WIN32_WIN32_C_MSYS_PATCHES
+        }
+      end
+
+      def patch_map_base
+        {
+          "template/Makefile.in" => template_makefile_in_patch,
+          "tool/mkconfig.rb" => tool_mkconfig_rb_patch,
+          "dir.c" => dir_c_patch, "dln.c" => dln_c_patch,
+          "io.c" => io_c_patch, "main.c" => PatchMain.get_main_c_patch(@ruby_ver),
+          "file.c" => PatchHelpers.patch_c_file_pre("/* define system APIs */"),
+          "util.c" => util_c_patch
+        }
+      end
+
+      def mlibs_subst
+        yjit_libs = @ruby_ver.ruby32only? ? "$(YJIT_LIBS) " : ""
+        {
+          "MAINLIBS = #{yjit_libs}@MAINLIBS@" =>
+            "# -- Start of tebako patch -- \n" \
+            "MAINLIBS = #{yjit_libs}#{PatchLibraries.mlibs(@ostype, @deps_lib_dir, @ruby_ver, true)}\n" \
+            "# -- End of tebako patch -- \n"
+        }
+      end
+
+      def template_makefile_in_patch
+        template_makefile_in_patch_two(@ruby_ver).merge(mlibs_subst)
+      end
+    end
+  end
+end
diff --git a/lib/tebako/packager/patch_buildsystem.rb b/lib/tebako/packager/patch_buildsystem.rb
index bb228554..7f52645b 100644
--- a/lib/tebako/packager/patch_buildsystem.rb
+++ b/lib/tebako/packager/patch_buildsystem.rb
@@ -77,8 +77,8 @@ module PatchBuildsystem
         "$(EXTOBJS) $(LIBRUBYARG_STATIC) $(OUTFLAG)$@\n" \
         "# -- End of tebako patch --"
 
-      def template_makefile_in_subst(ostype, ruby_ver)
-        if PatchHelpers.msys?(ostype)
+      def template_makefile_in_subst(ruby_ver)
+        if ScenarioManagerBase.new.msys?
           TEMPLATE_MAKEFILE_IN_BASE_PATCH_MSYS
         elsif !ruby_ver.ruby31?
           TEMPLATE_MAKEFILE_IN_BASE_PATCH_PRE_3_1
@@ -87,16 +87,20 @@ def template_makefile_in_subst(ostype, ruby_ver)
         end
       end
 
-      def template_makefile_in_patch_two(ostype, ruby_ver)
+      def template_makefile_in_patch_two(ruby_ver)
         if !ruby_ver.ruby31?
-          { TEMPLATE_MAKEFILE_IN_BASE_PATTERN_PRE_3_1 => template_makefile_in_subst(ostype, ruby_ver) }
+          { TEMPLATE_MAKEFILE_IN_BASE_PATTERN_PRE_3_1 => template_makefile_in_subst(ruby_ver) }
         elsif !ruby_ver.ruby33?
-          { TEMPLATE_MAKEFILE_IN_BASE_PATTERN_PRE_3_3 => template_makefile_in_subst(ostype, ruby_ver) }
+          { TEMPLATE_MAKEFILE_IN_BASE_PATTERN_PRE_3_3 => template_makefile_in_subst(ruby_ver) }
         else
-          { TEMPLATE_MAKEFILE_IN_BASE_PATTERN => template_makefile_in_subst(ostype, ruby_ver) }
+          { TEMPLATE_MAKEFILE_IN_BASE_PATTERN => template_makefile_in_subst(ruby_ver) }
         end
       end
 
+      GNUMAKEFILE_IN_DLLTOOL_SUBST = <<~SUBST
+        $(Q) dlltool --output-lib=$(LIBRUBY) --output-def=tebako.def --export-all $(LIBRUBY_A) --output-exp=$(RUBY_EXP)   # tebako patched
+      SUBST
+
       # This MSYS specific thing ensure compilation of winmain.c
       # Did try to understand why it did not work out of the box
       GNUMAKEFILE_IN_WINMAIN_SUBST = <<~SUBST
diff --git a/lib/tebako/packager/patch_helpers.rb b/lib/tebako/packager/patch_helpers.rb
index 081ecf79..9e92a209 100755
--- a/lib/tebako/packager/patch_helpers.rb
+++ b/lib/tebako/packager/patch_helpers.rb
@@ -62,18 +62,6 @@ def get_prefix_linux(package)
           out
         end
 
-        def exe_suffix(ostype)
-          msys?(ostype) ? ".exe" : ""
-        end
-
-        def msys?(ostype)
-          ostype =~ /msys|cygwin|mingw/
-        end
-
-        def macos?(ostype)
-          ostype =~ /darwin/
-        end
-
         def patch_c_file_pre(pattern)
           {
             pattern => "#{PatchLiterals::C_FILE_SUBST}\n#{pattern}"
diff --git a/lib/tebako/ruby_builder.rb b/lib/tebako/ruby_builder.rb
index abc5b456..070f36a5 100644
--- a/lib/tebako/ruby_builder.rb
+++ b/lib/tebako/ruby_builder.rb
@@ -37,7 +37,7 @@ class RubyBuilder
     def initialize(ruby_ver, src_dir)
       @ruby_ver = ruby_ver
       @src_dir = src_dir
-      @ncores = BuildHelpers.ncores
+      @ncores = ScenarioManagerBase.new.ncores
     end
 
     # Final build of tebako package
diff --git a/lib/tebako/ruby_version.rb b/lib/tebako/ruby_version.rb
index 4f43fedd..8808b369 100755
--- a/lib/tebako/ruby_version.rb
+++ b/lib/tebako/ruby_version.rb
@@ -120,8 +120,7 @@ def version_check_format
     end
 
     def version_check_msys
-      if Gem::Version.new(@ruby_version) < Gem::Version.new(MIN_RUBY_VERSION_WINDOWS) &&
-         RUBY_PLATFORM =~ /msys|mingw|cygwin/
+      if Gem::Version.new(@ruby_version) < Gem::Version.new(MIN_RUBY_VERSION_WINDOWS) && ScenarioManagerBase.new.msys?
         raise Tebako::Error.new("Ruby version #{@ruby_version} is not supported on Windows", 111)
       end
     end
diff --git a/lib/tebako/scenario_manager.rb b/lib/tebako/scenario_manager.rb
index 89c597ac..83117e53 100644
--- a/lib/tebako/scenario_manager.rb
+++ b/lib/tebako/scenario_manager.rb
@@ -38,47 +38,93 @@ module Tebako
   BUNDLER_VERSION = "2.4.22"
   RUBYGEMS_VERSION = "3.4.22"
 
-  # Manages packaging scenario based on input files (gemfile, gemspec, etc)
-  class ScenarioManager
-    def initialize(fs_root, fs_entrance)
-      @with_gemfile = @with_lockfile = @needs_bundler = false
-      @bundler_version = BUNDLER_VERSION
-      initialize_root(fs_root)
-      initialize_entry_point(fs_entrance || "stub.rb")
+  # A couple of static Scenario definitions
+  class ScenarioManagerBase
+    def initialize(ostype = RUBY_PLATFORM)
+      @ostype = ostype
+      @linux = @ostype =~ /linux/ ? true : false
+      @musl = @ostype =~ /linux-musl/ ? true : false
+      @macos = @ostype =~ /darwin/ ? true : false
+      @msys  = @ostype =~ /msys|mingw|cygwin/ ? true : false
+
+      @fs_mount_point = @msys ? "A:/__tebako_memfs__" : "/__tebako_memfs__"
+      @exe_suffix = @msys ? ".exe" : ""
     end
 
-    attr_reader :fs_entry_point, :fs_mount_point, :fs_entrance, :gemfile_path, :needs_bundler, :with_gemfile
+    attr_reader :fs_mount_point, :exe_suffix
 
-    def bundler_reference
-      @needs_bundler ? "_#{@bundler_version}_" : nil
+    def b_env
+      u_flags = if @macos
+                  "-DTARGET_OS_SIMULATOR=0 -DTARGET_OS_IPHONE=0  #{ENV.fetch("CXXFLAGS", nil)}"
+                else
+                  ENV.fetch("CXXFLAGS", nil)
+                end
+      @b_env ||= { "CXXFLAGS" => u_flags }
     end
 
-    def configure_scenario
-      @fs_mount_point = if msys?
-                          "A:/__tebako_memfs__"
-                        else
-                          "/__tebako_memfs__"
-                        end
-
-      lookup_files
-      configure_scenario_inner
+    def linux?
+      @linux
     end
 
-    def exe_suffix
-      @exe_suffix ||= msys? ? ".exe" : ""
+    def m_files
+      # [TODO]
+      # Ninja generates incorrect script for tebako press target -- gets lost in a chain custom targets
+      # Using makefiles has negative performance impact so it needs to be fixed
+
+      @m_files ||= if @linux || @macos
+                     "Unix Makefiles"
+                   elsif @msys
+                     "MinGW Makefiles"
+                   else
+                     raise Tebako::Error.new("#{RUBY_PLATFORM} is not supported.", 112)
+                   end
     end
 
     def macos?
-      @macos ||= RUBY_PLATFORM =~ /darwin/ ? true : false
+      @macos
     end
 
     def msys?
-      @msys ||= RUBY_PLATFORM =~ /msys|mingw|cygwin/ ? true : false
+      @msys
     end
 
-    private
+    def musl?
+      @musl
+    end
+
+    def ncores
+      if @ncores.nil?
+        if @macos
+          out, st = Open3.capture2e("sysctl", "-n", "hw.ncpu")
+        else
+          out, st = Open3.capture2e("nproc", "--all")
+        end
+
+        @ncores = !st.signaled? && st.exitstatus.zero? ? out.strip.to_i : 4
+      end
+      @ncores
+    end
+  end
+
+  # Manages packaging scenario based on input files (gemfile, gemspec, etc)
+  class ScenarioManager < ScenarioManagerBase
+    def initialize(fs_root, fs_entrance)
+      super()
+      @with_gemfile = @with_lockfile = @needs_bundler = false
+      @bundler_version = BUNDLER_VERSION
+      initialize_root(fs_root)
+      initialize_entry_point(fs_entrance || "stub.rb")
+    end
+
+    attr_reader :fs_entry_point, :fs_entrance, :gemfile_path, :needs_bundler, :with_gemfile
+
+    def bundler_reference
+      @needs_bundler ? "_#{@bundler_version}_" : nil
+    end
+
+    def configure_scenario
+      lookup_files
 
-    def configure_scenario_inner
       case @gs_length
       when 0
         configure_scenario_no_gemspec
@@ -89,6 +135,8 @@ def configure_scenario_inner
       end
     end
 
+    private
+
     def configure_scenario_no_gemspec
       @fs_entry_point = "/local/#{@fs_entrance}" if @with_gemfile || @g_length.zero?
 
diff --git a/spec/build_helpers_spec.rb b/spec/build_helpers_spec.rb
index 22ad863c..40eec602 100644
--- a/spec/build_helpers_spec.rb
+++ b/spec/build_helpers_spec.rb
@@ -31,55 +31,7 @@
 # rubocop:disable Metrics/BlockLength
 
 RSpec.describe Tebako::BuildHelpers do
-  describe ".ncores" do
-    context "when on macOS" do
-      before do
-        stub_const("RUBY_PLATFORM", "darwin")
-        status_double = double(exitstatus: 0, signaled?: false)
-        allow(Open3).to receive(:capture2e).with("sysctl", "-n", "hw.ncpu").and_return(["4", status_double])
-      end
-
-      it "returns the number of cores" do
-        expect(described_class.ncores).to eq(4)
-      end
-    end
-
-    context "when on Linux" do
-      before do
-        stub_const("RUBY_PLATFORM", "linux")
-        status_double = double(exitstatus: 0, signaled?: false)
-        allow(Open3).to receive(:capture2e).with("nproc", "--all").and_return(["8", status_double])
-      end
-
-      it "returns the number of cores" do
-        expect(described_class.ncores).to eq(8)
-      end
-    end
-
-    context "when the command fails" do
-      before do
-        status_double = double(exitstatus: 1, signaled?: false)
-        allow(Open3).to receive(:capture2e).and_return(["", status_double])
-      end
-
-      it "returns 4 as a default value" do
-        expect(described_class.ncores).to eq(4)
-      end
-    end
-
-    context "when the command is terminated by a signal" do
-      before do
-        status_double = double(exitstatus: nil, signaled?: true, termsig: 9)
-        allow(Open3).to receive(:capture2e).and_return(["", status_double])
-      end
-
-      it "returns 4 as a default value" do
-        expect(described_class.ncores).to eq(4)
-      end
-    end
-  end
-
-  describe ".run_with_capture" do
+  describe "#run_with_capture" do
     let(:args) { %w[echo hello] }
 
     describe ".run_with_capture" do
diff --git a/spec/deploy_helper_spec.rb b/spec/deploy_helper_spec.rb
index 097677a3..d31432e5 100644
--- a/spec/deploy_helper_spec.rb
+++ b/spec/deploy_helper_spec.rb
@@ -52,7 +52,6 @@
       expect(deploy_helper.instance_variable_get(:@target_dir)).to eq(target_dir)
       expect(deploy_helper.instance_variable_get(:@pre_dir)).to eq(pre_dir)
       expect(deploy_helper.instance_variable_get(:@verbose)).to eq(false)
-      expect(deploy_helper.instance_variable_get(:@ncores)).to be_a(Integer)
     end
   end
 
@@ -180,8 +179,7 @@
     before do
       allow(Tebako::BuildHelpers).to receive(:ncores).and_return(1) if RUBY_PLATFORM =~ /darwin/
       stub_const("RUBY_PLATFORM", "linux")
-      allow(deploy_helper).to receive(:lookup_files)
-      allow(deploy_helper).to receive(:configure_scenario_inner)
+      allow(deploy_helper).to receive(:configure_scenario)
       deploy_helper.configure(ruby_ver, cwd)
     end
 
@@ -338,8 +336,7 @@
     before do
       allow(Tebako::BuildHelpers).to receive(:ncores).and_return(1) if RUBY_PLATFORM =~ /darwin/
       stub_const("RUBY_PLATFORM", "linux")
-      allow(deploy_helper).to receive(:lookup_files)
-      allow(deploy_helper).to receive(:configure_scenario_inner)
+      allow(deploy_helper).to receive(:configure_scenario)
       deploy_helper.configure(ruby_ver, cwd)
     end
 
@@ -521,7 +518,7 @@
       expect(deploy_helper).to receive(:bundle_config).ordered
       expect(Tebako::BuildHelpers).to receive(:run_with_capture_v)
         .with([deploy_helper.instance_variable_get(:@bundler_command), nil, "install",
-               "--jobs=#{deploy_helper.instance_variable_get(:@ncores)}"])
+               "--jobs=#{deploy_helper.ncores}"])
         .ordered
       expect(deploy_helper).to receive(:check_entry_point).with("local").ordered
 
@@ -765,4 +762,5 @@
     end
   end
 end
+
 # rubocop:enable Metrics/BlockLength
diff --git a/spec/options_manager_spec.rb b/spec/options_manager_spec.rb
index 50ca273c..d5f71e9a 100644
--- a/spec/options_manager_spec.rb
+++ b/spec/options_manager_spec.rb
@@ -37,48 +37,6 @@
   let(:ruby_ver) { "3.2.6" }
   let(:ruby_hash) { Tebako::RubyVersion::RUBY_VERSIONS["3.2.6"] }
 
-  describe "#b_env" do
-    let(:options_manager) { Tebako::OptionsManager.new({}) }
-    before do
-      @original_host_os = RbConfig::CONFIG["host_os"]
-      @original_cxxflags = ENV.fetch("CXXFLAGS", nil)
-    end
-
-    after do
-      RbConfig::CONFIG["host_os"] = @original_host_os
-      ENV["CXXFLAGS"] = @original_cxxflags
-    end
-
-    context "when host OS is Darwin" do
-      it "sets CXXFLAGS with TARGET_OS_SIMULATOR and TARGET_OS_IPHONE" do
-        RbConfig::CONFIG["host_os"] = "darwin"
-        ENV["CXXFLAGS"] = "-O2"
-
-        expected_flags = "-DTARGET_OS_SIMULATOR=0 -DTARGET_OS_IPHONE=0  -O2"
-        expect(options_manager.b_env["CXXFLAGS"]).to eq(expected_flags)
-      end
-    end
-
-    context "when host OS is not Darwin" do
-      it "sets CXXFLAGS with the value from ENV" do
-        RbConfig::CONFIG["host_os"] = "linux"
-        ENV["CXXFLAGS"] = "-O2"
-
-        expected_flags = "-O2"
-        expect(options_manager.b_env["CXXFLAGS"]).to eq(expected_flags)
-      end
-    end
-
-    context "when CXXFLAGS is not set in ENV" do
-      it "sets CXXFLAGS to nil" do
-        RbConfig::CONFIG["host_os"] = "linux"
-        ENV.delete("CXXFLAGS")
-
-        expect(options_manager.b_env["CXXFLAGS"]).to be_nil
-      end
-    end
-  end
-
   describe "#cfg_options" do
     let(:deps) { File.join(Dir.pwd, "deps") }
     let(:output_folder) { File.join(Dir.pwd, "o") }
@@ -250,50 +208,6 @@
     end
   end
 
-  describe "#m_files" do
-    let(:options) { {} }
-    let(:options_manager) { Tebako::OptionsManager.new(options) }
-    context "when on a Linux platform" do
-      before do
-        stub_const("RUBY_PLATFORM", "linux")
-      end
-
-      it 'returns "Unix Makefiles"' do
-        expect(options_manager.m_files).to eq("Unix Makefiles")
-      end
-    end
-
-    context "when on a macOS platform" do
-      before do
-        stub_const("RUBY_PLATFORM", "darwin")
-      end
-
-      it 'returns "Unix Makefiles"' do
-        expect(options_manager.m_files).to eq("Unix Makefiles")
-      end
-    end
-
-    context "when on a Windows platform" do
-      before do
-        stub_const("RUBY_PLATFORM", "msys")
-      end
-
-      it 'returns "MinGW Makefiles"' do
-        expect(options_manager.m_files).to eq("MinGW Makefiles")
-      end
-    end
-
-    context "when on an unsupported platform" do
-      before do
-        stub_const("RUBY_PLATFORM", "unsupported")
-      end
-
-      it "raises a Tebako::Error" do
-        expect { options_manager.m_files }.to raise_error(Tebako::Error, "unsupported is not supported.")
-      end
-    end
-  end
-
   describe "#package" do
     let(:options_manager) { OptionsManager.new(options) }
 
diff --git a/spec/packager/pass2_patch_spec.rb b/spec/packager/pass2_patch_spec.rb
new file mode 100644
index 00000000..68817ea0
--- /dev/null
+++ b/spec/packager/pass2_patch_spec.rb
@@ -0,0 +1,190 @@
+# frozen_string_literal: true
+
+# Copyright (c) 2025 [Ribose Inc](https://www.ribose.com).
+# All rights reserved.
+# This file is a part of tebako
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+# TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+# PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS
+# BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.
+
+# rubocop:disable Metrics/BlockLength
+RSpec.describe Tebako::Packager::Pass2Patch do
+  let(:ostype) { "linux-gnu" }
+  let(:deps_lib_dir) { "deps/lib" }
+  let(:ruby_ver) do
+    double("RubyVersion", ruby34?: false, ruby3x?: true, ruby32only?: true, ruby33?: false, ruby32?: false,
+                          ruby31?: false)
+  end
+  let(:patch) { described_class.new(ostype, deps_lib_dir, ruby_ver) }
+  let(:scmb) { instance_double(Tebako::ScenarioManagerBase, msys?: false, musl?: false) }
+
+  before do
+    allow(Tebako::ScenarioManagerBase).to receive(:new).and_return(scmb)
+  end
+
+  describe "#initialize" do
+    it "sets instance variables correctly" do
+      expect(patch.instance_variable_get(:@ostype)).to eq(ostype)
+      expect(patch.instance_variable_get(:@deps_lib_dir)).to eq(deps_lib_dir)
+      expect(patch.instance_variable_get(:@ruby_ver)).to eq(ruby_ver)
+    end
+  end
+
+  describe "#patch_map" do
+    context "when on musl platform" do
+      before { allow(scmb).to receive(:musl?).and_return(true) }
+
+      it "includes LINUX_MUSL_THREAD_PTHREAD_PATCH" do
+        expect(patch.patch_map).to include("thread_pthread.c" => described_class::LINUX_MUSL_THREAD_PTHREAD_PATCH)
+      end
+    end
+
+    context "when on msys platform" do
+      before do
+        allow(scmb).to receive(:msys?).and_return(true)
+        allow(patch).to receive(:msys_patches).and_return({ "msys_file" => "msys_patch" })
+      end
+
+      it "includes msys patches" do
+        expect(patch.patch_map).to include("msys_file" => "msys_patch")
+      end
+    end
+
+    context "when ruby version is 3.x" do
+      before { allow(ruby_ver).to receive(:ruby3x?).and_return(true) }
+
+      it "includes COMMON_MK_PATCH when not on msys" do
+        expect(patch.patch_map).to include("common.mk" => described_class::COMMON_MK_PATCH)
+      end
+    end
+
+    context "when ruby version is 3.3" do
+      before do
+        allow(ruby_ver).to receive(:ruby33?).and_return(true)
+        allow(patch).to receive(:get_config_status_patch).and_return("config_status_patch")
+      end
+
+      it "includes config.status patch" do
+        expect(patch.patch_map).to include("config.status" => "config_status_patch")
+      end
+    end
+
+    context "when ruby version is 3.4" do
+      before { allow(ruby_ver).to receive(:ruby34?).and_return(true) }
+
+      it "includes PRISM_PATCHES" do
+        expect(patch.patch_map).to include("prism_compile.c" => described_class::PRISM_PATCHES)
+      end
+    end
+  end
+
+  describe "#patch_map_base" do
+    it "includes all base patches" do
+      base_patches = patch.send(:patch_map_base)
+      expect(base_patches.keys).to include(
+        "template/Makefile.in",
+        "tool/mkconfig.rb",
+        "dir.c",
+        "dln.c",
+        "io.c",
+        "main.c",
+        "file.c",
+        "util.c"
+      )
+    end
+  end
+
+  describe "#dir_c_patch" do
+    context "when on msys" do
+      let(:ostype) { "msys" }
+      before { allow(scmb).to receive(:msys?).and_return(true) }
+
+      it "uses correct pattern for msys" do
+        patch = described_class.new(ostype, deps_lib_dir, ruby_ver)
+        expect(patch.send(:dir_c_patch)).to include("/* define system APIs */" => anything)
+      end
+    end
+
+    context "when not on msys" do
+      before { allow(scmb).to receive(:msys?).and_return(false) }
+
+      it "uses correct pattern for non-msys" do
+        patch = described_class.new(ostype, deps_lib_dir, ruby_ver)
+        expect(patch.send(:dir_c_patch)).to include("#ifdef HAVE_GETATTRLIST" => anything)
+      end
+    end
+  end
+
+  describe "#msys_patches" do
+    let(:expected_gnumakefile_patch) { "gnumakefile_patch_content" }
+
+    before do
+      allow(patch).to receive(:get_gnumakefile_in_patch_p2)
+        .with(ruby_ver)
+        .and_return(expected_gnumakefile_patch)
+    end
+
+    it "returns correct patches for MSys platform" do
+      expected_patches = {
+        "cygwin/GNUmakefile.in" => expected_gnumakefile_patch,
+        "ruby.c" => described_class::RUBY_C_MSYS_PATCHES,
+        "win32/file.c" => described_class::WIN32_FILE_C_MSYS_PATCHES,
+        "win32/win32.c" => described_class::WIN32_WIN32_C_MSYS_PATCHES
+      }
+
+      expect(patch.send(:msys_patches)).to eq(expected_patches)
+    end
+
+    it "calls get_gnumakefile_in_patch_p2 with correct ruby_ver" do
+      expect(patch).to receive(:get_gnumakefile_in_patch_p2).with(ruby_ver)
+      patch.send(:msys_patches)
+    end
+  end
+
+  describe "#util_c_patch" do
+    context "when ruby version is 3.1" do
+      before do
+        allow(ruby_ver).to receive(:ruby31?).and_return(true)
+      end
+
+      it "uses post-pattern for ruby 3.1" do
+        patch = described_class.new(ostype, deps_lib_dir, ruby_ver)
+        expect(Tebako::Packager::PatchHelpers).to receive(:patch_c_file_post)
+          .with("#endif /* !HAVE_GNU_QSORT_R */")
+        patch.send(:util_c_patch)
+      end
+    end
+
+    context "when ruby version is not 3.1" do
+      before do
+        allow(ruby_ver).to receive(:ruby31?).and_return(false)
+      end
+
+      it "uses pre-pattern for non-ruby 3.1" do
+        patch = described_class.new(ostype, deps_lib_dir, ruby_ver)
+        expect(Tebako::Packager::PatchHelpers).to receive(:patch_c_file_pre)
+          .with("#ifndef S_ISDIR")
+        patch.send(:util_c_patch)
+      end
+    end
+  end
+end
+# rubocop:enable Metrics/BlockLength
diff --git a/spec/packager/patch_helpers_spec.rb b/spec/packager/patch_helpers_spec.rb
index c5319da4..82fb6cc3 100644
--- a/spec/packager/patch_helpers_spec.rb
+++ b/spec/packager/patch_helpers_spec.rb
@@ -105,19 +105,6 @@
     end
   end
 
-  describe "#exe_suffix" do
-    it "returns '.exe' for msys-based platforms" do
-      expect(Tebako::Packager::PatchHelpers.exe_suffix("msys2")).to eq(".exe")
-      expect(Tebako::Packager::PatchHelpers.exe_suffix("mingw32")).to eq(".exe")
-      expect(Tebako::Packager::PatchHelpers.exe_suffix("cygwin")).to eq(".exe")
-    end
-
-    it "returns an empty string for non-msys platforms" do
-      expect(Tebako::Packager::PatchHelpers.exe_suffix("darwin")).to eq("")
-      expect(Tebako::Packager::PatchHelpers.exe_suffix("linux")).to eq("")
-    end
-  end
-
   describe "#restore_and_save_files" do # rubocop:disable Metrics/BlockLength
     let(:ruby_source_dir) { File.join(temp_dir, "ruby_source") }
     let(:test_files) { ["test1.rb", "test2.rb"] }
diff --git a/spec/packager_spec.rb b/spec/packager_spec.rb
index 2205e3a1..38f0f633 100644
--- a/spec/packager_spec.rb
+++ b/spec/packager_spec.rb
@@ -96,7 +96,6 @@
   end
 
   describe "#finalize" do
-    let(:os_type) { "linux" }
     let(:src_dir) { "/path/to/src" }
     let(:app_name) { "my_app" }
     let(:ruby_ver) { "2.7.2" }
@@ -106,32 +105,32 @@
     before do
       allow(Tebako::RubyBuilder).to receive(:new).and_return(ruby_builder)
       allow(ruby_builder).to receive(:target_build)
-      allow(Tebako::Packager::PatchHelpers).to receive(:exe_suffix).and_return("")
+      allow_any_instance_of(Tebako::ScenarioManagerBase).to receive(:exe_suffix).and_return("")
       allow(Tebako::Packager).to receive(:patchelf)
-      allow(Tebako::Packager).to receive(:strip_or_copy)
+      allow(Tebako::Stripper).to receive(:strip)
     end
 
     it "creates a new RubyBuilder with the correct parameters" do
       expect(Tebako::RubyBuilder).to receive(:new).with(ruby_ver, src_dir).and_return(ruby_builder)
-      Tebako::Packager.finalize(os_type, src_dir, app_name, ruby_ver, patchelf)
+      Tebako::Packager.finalize(src_dir, app_name, ruby_ver, patchelf)
     end
 
     it "calls target_build on the RubyBuilder" do
       expect(ruby_builder).to receive(:target_build)
-      Tebako::Packager.finalize(os_type, src_dir, app_name, ruby_ver, patchelf)
+      Tebako::Packager.finalize(src_dir, app_name, ruby_ver, patchelf)
     end
 
     it "calls patchelf with the correct parameters" do
       src_name = File.join(src_dir, "ruby")
       expect(Tebako::Packager).to receive(:patchelf).with(src_name, patchelf)
-      Tebako::Packager.finalize(os_type, src_dir, app_name, ruby_ver, patchelf)
+      Tebako::Packager.finalize(src_dir, app_name, ruby_ver, patchelf)
     end
 
-    it "calls strip_or_copy with the correct parameters" do
+    it "calls strip_file with the correct parameters" do
       src_name = File.join(src_dir, "ruby")
       package_name = app_name.to_s
-      expect(Tebako::Packager).to receive(:strip_or_copy).with(os_type, src_name, package_name)
-      Tebako::Packager.finalize(os_type, src_dir, app_name, ruby_ver, patchelf)
+      expect(Tebako::Stripper).to receive(:strip_file).with(src_name, package_name)
+      Tebako::Packager.finalize(src_dir, app_name, ruby_ver, patchelf)
     end
   end
 
@@ -244,7 +243,7 @@
     let(:patch_map) { { "file1" => "patch1", "file2" => "patch2" } }
 
     before do
-      allow(Tebako::Packager::Pass2).to receive(:get_patch_map).and_return(patch_map)
+      allow_any_instance_of(Tebako::Packager::Pass2Patch).to receive(:patch_map).and_return(patch_map)
       allow(Tebako::Packager).to receive(:do_patch)
     end
 
@@ -310,34 +309,6 @@
       end
     end
   end
-
-  describe "#strip_or_copy" do
-    let(:os_type) { "linux" }
-    let(:src_name) { "binary" }
-    let(:package_name) { "package" }
-
-    context "when running on MSys" do
-      before do
-        allow(Tebako::Packager::PatchHelpers).to receive(:msys?).with(os_type).and_return(true)
-      end
-
-      it "copies the file" do
-        expect(FileUtils).to receive(:cp).with(src_name, package_name)
-        Tebako::Packager.send(:strip_or_copy, os_type, src_name, package_name)
-      end
-    end
-
-    context "when not running on MSys" do
-      before do
-        allow(Tebako::Packager::PatchHelpers).to receive(:msys?).with(os_type).and_return(false)
-      end
-
-      it "strips the file" do
-        expect(Tebako::Stripper).to receive(:strip_file).with(src_name, package_name)
-        Tebako::Packager.send(:strip_or_copy, os_type, src_name, package_name)
-      end
-    end
-  end
 end
 
 # rubocop:enable Metrics/BlockLength
diff --git a/spec/ruby_builder_spec.rb b/spec/ruby_builder_spec.rb
index cc494c95..bd796aa2 100644
--- a/spec/ruby_builder_spec.rb
+++ b/spec/ruby_builder_spec.rb
@@ -39,7 +39,7 @@
     let(:builder) { described_class.new(Tebako::RubyVersion.new(ruby_ver), src_dir) }
 
     before do
-      allow(Tebako::BuildHelpers).to receive(:ncores).and_return(ncores)
+      allow_any_instance_of(Tebako::ScenarioManagerBase).to receive(:ncores).and_return(ncores)
       allow(Tebako::BuildHelpers).to receive(:run_with_capture)
       allow(Dir).to receive(:chdir).with(src_dir).and_yield
     end
@@ -73,7 +73,7 @@
     let(:builder) { described_class.new(Tebako::RubyVersion.new(ruby_ver), src_dir) }
 
     before do
-      allow(Tebako::BuildHelpers).to receive(:ncores).and_return(ncores)
+      allow_any_instance_of(Tebako::ScenarioManagerBase).to receive(:ncores).and_return(ncores)
       allow(Tebako::BuildHelpers).to receive(:run_with_capture)
       allow(Dir).to receive(:chdir).with(src_dir).and_yield
     end
diff --git a/spec/scenario_manager_base_spec.rb b/spec/scenario_manager_base_spec.rb
new file mode 100644
index 00000000..9285f8c4
--- /dev/null
+++ b/spec/scenario_manager_base_spec.rb
@@ -0,0 +1,277 @@
+# frozen_string_literal: true
+
+# Copyright (c) 2024-2025 [Ribose Inc](https://www.ribose.com).
+# All rights reserved.
+# This file is a part of tebako
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+# TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+# PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS
+# BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.
+
+require "tmpdir"
+require_relative "../lib/tebako/scenario_manager"
+
+# rubocop:disable Metrics/BlockLength
+RSpec.describe Tebako::ScenarioManagerBase do
+  describe "#initialize" do
+    context "on msys platform" do
+      before do
+        stub_const("RUBY_PLATFORM", "msys")
+      end
+
+      it "sets correct fs_mount_point and exe_suffix" do
+        manager = described_class.new
+        expect(manager.fs_mount_point).to eq("A:/__tebako_memfs__")
+        expect(manager.exe_suffix).to eq(".exe")
+      end
+    end
+
+    context "on non-msys platform" do
+      before do
+        stub_const("RUBY_PLATFORM", "linux")
+      end
+
+      it "sets correct fs_mount_point and exe_suffix" do
+        manager = described_class.new
+        expect(manager.fs_mount_point).to eq("/__tebako_memfs__")
+        expect(manager.exe_suffix).to eq("")
+      end
+    end
+  end
+
+  describe "#b_env" do
+    before do
+      @original_cxxflags = ENV.fetch("CXXFLAGS", nil)
+    end
+
+    after do
+      ENV["CXXFLAGS"] = @original_cxxflags
+    end
+
+    context "when host OS is Darwin" do
+      it "sets CXXFLAGS with TARGET_OS_SIMULATOR and TARGET_OS_IPHONE" do
+        stub_const("RUBY_PLATFORM", "darwin")
+        ENV["CXXFLAGS"] = "-O2"
+
+        expected_flags = "-DTARGET_OS_SIMULATOR=0 -DTARGET_OS_IPHONE=0  -O2"
+        expect(described_class.new.b_env["CXXFLAGS"]).to eq(expected_flags)
+      end
+    end
+
+    context "when host OS is not Darwin" do
+      it "sets CXXFLAGS with the value from ENV" do
+        stub_const("RUBY_PLATFORM", "linux")
+        ENV["CXXFLAGS"] = "-O2"
+
+        expected_flags = "-O2"
+        expect(described_class.new.b_env["CXXFLAGS"]).to eq(expected_flags)
+      end
+    end
+
+    context "when CXXFLAGS is not set in ENV" do
+      it "sets CXXFLAGS to nil" do
+        stub_const("RUBY_PLATFORM", "linux")
+        ENV.delete("CXXFLAGS")
+
+        expect(described_class.new.b_env["CXXFLAGS"]).to be_nil
+      end
+    end
+  end
+
+  describe "#linux?" do
+    context "on linux platform" do
+      before do
+        stub_const("RUBY_PLATFORM", "linux")
+      end
+
+      it "returns true" do
+        expect(described_class.new.linux?).to be true
+      end
+    end
+
+    context "on non-linux platform" do
+      before do
+        stub_const("RUBY_PLATFORM", "darwin")
+      end
+
+      it "returns false" do
+        expect(described_class.new.linux?).to be false
+      end
+    end
+  end
+
+  describe "#musl?" do
+    context "on linux-musl platform" do
+      before do
+        stub_const("RUBY_PLATFORM", "linux-musl")
+      end
+
+      it "returns true" do
+        expect(described_class.new.musl?).to be true
+      end
+    end
+
+    context "on non-linux platform" do
+      before do
+        stub_const("RUBY_PLATFORM", "darwin")
+      end
+
+      it "returns false" do
+        expect(described_class.new.musl?).to be false
+      end
+    end
+  end
+
+  describe "#m_files" do
+    context "when on a Linux platform" do
+      before do
+        stub_const("RUBY_PLATFORM", "linux")
+      end
+
+      it 'returns "Unix Makefiles"' do
+        expect(described_class.new.m_files).to eq("Unix Makefiles")
+      end
+    end
+
+    context "when on a macOS platform" do
+      before do
+        stub_const("RUBY_PLATFORM", "darwin")
+      end
+
+      it 'returns "Unix Makefiles"' do
+        expect(described_class.new.m_files).to eq("Unix Makefiles")
+      end
+    end
+
+    context "when on a Windows platform" do
+      before do
+        stub_const("RUBY_PLATFORM", "msys")
+      end
+
+      it 'returns "MinGW Makefiles"' do
+        expect(described_class.new.m_files).to eq("MinGW Makefiles")
+      end
+    end
+
+    context "when on an unsupported platform" do
+      before do
+        stub_const("RUBY_PLATFORM", "unsupported")
+      end
+
+      it "raises a Tebako::Error" do
+        expect { described_class.new.m_files }.to raise_error(Tebako::Error, "unsupported is not supported.")
+      end
+    end
+  end
+
+  describe "#macos?" do
+    context "on macos platform" do
+      before do
+        stub_const("RUBY_PLATFORM", "darwin")
+      end
+
+      it "returns true" do
+        expect(described_class.new.macos?).to be true
+      end
+    end
+
+    context "on non-macos platform" do
+      before do
+        stub_const("RUBY_PLATFORM", "linux")
+      end
+
+      it "returns false" do
+        expect(described_class.new.macos?).to be false
+      end
+    end
+  end
+
+  describe "#msys?" do
+    context "on msys platform" do
+      before do
+        stub_const("RUBY_PLATFORM", "msys")
+      end
+
+      it "returns true" do
+        expect(described_class.new.msys?).to be true
+      end
+    end
+
+    context "on non-msys platform" do
+      before do
+        stub_const("RUBY_PLATFORM", "darwin")
+      end
+
+      it "returns false" do
+        expect(described_class.new.msys?).to be false
+      end
+    end
+  end
+
+  describe "#ncores" do
+    context "when on macOS" do
+      before do
+        stub_const("RUBY_PLATFORM", "darwin")
+        status_double = double(exitstatus: 0, signaled?: false)
+        allow(Open3).to receive(:capture2e).with("sysctl", "-n", "hw.ncpu").and_return(["4", status_double])
+      end
+
+      it "returns the number of cores" do
+        expect(described_class.new.ncores).to eq(4)
+      end
+    end
+
+    context "when on Linux" do
+      before do
+        stub_const("RUBY_PLATFORM", "linux")
+        status_double = double(exitstatus: 0, signaled?: false)
+        allow(Open3).to receive(:capture2e).with("nproc", "--all").and_return(["8", status_double])
+      end
+
+      it "returns the number of cores" do
+        expect(described_class.new.ncores).to eq(8)
+      end
+    end
+
+    context "when the command fails" do
+      before do
+        status_double = double(exitstatus: 1, signaled?: false)
+        allow(Open3).to receive(:capture2e).and_return(["", status_double])
+      end
+
+      it "returns 4 as a default value" do
+        expect(described_class.new.ncores).to eq(4)
+      end
+    end
+
+    context "when the command is terminated by a signal" do
+      before do
+        status_double = double(exitstatus: nil, signaled?: true, termsig: 9)
+        allow(Open3).to receive(:capture2e).and_return(["", status_double])
+      end
+
+      it "returns 4 as a default value" do
+        expect(described_class.new.ncores).to eq(4)
+      end
+    end
+  end
+end
+
+# rubocop:enable Metrics/BlockLength
diff --git a/spec/scenario_manager_spec.rb b/spec/scenario_manager_spec.rb
index 34e3d839..c1d9fb02 100644
--- a/spec/scenario_manager_spec.rb
+++ b/spec/scenario_manager_spec.rb
@@ -52,7 +52,6 @@
       it "sets instance variables correctly" do
         expect(scenario_manager.instance_variable_get(:@fs_root)).to eq(fs_root)
         expect(scenario_manager.instance_variable_get(:@fs_entrance)).to eq(fs_entrance)
-        expect(scenario_manager.instance_variable_get(:@fs_mount_point)).to eq("/__tebako_memfs__")
       end
     end
 
@@ -65,73 +64,76 @@
       it "sets instance variables correctly" do
         expect(scenario_manager.instance_variable_get(:@fs_root)).to eq(fs_root)
         expect(scenario_manager.instance_variable_get(:@fs_entrance)).to eq(fs_entrance)
-        expect(scenario_manager.instance_variable_get(:@fs_mount_point)).to eq("A:/__tebako_memfs__")
       end
     end
   end
 
-  describe "#configure_scenario_inner" do
+  describe "#configure_scenario" do
     before do
       allow(scenario_manager).to receive(:lookup_files)
-      allow(scenario_manager).to receive(:configure_scenario_inner)
-      scenario_manager.configure_scenario
     end
 
-    it "calls configure_scenario_inner" do
-      expect(scenario_manager).to have_received(:configure_scenario_inner)
-    end
-  end
-
-  describe "#configure_scenario" do
-    context "when @gs_length is 0" do
+    context "when no gemspecs are present" do
       before do
         scenario_manager.instance_variable_set(:@gs_length, 0)
+        scenario_manager.instance_variable_set(:@g_length, 0)
+      end
+
+      it "sets scenario to :simple_script" do
+        scenario_manager.configure_scenario
+        expect(scenario_manager.instance_variable_get(:@scenario)).to eq(:simple_script)
       end
 
-      it "calls configure_scenario_no_gemspec" do
-        expect(scenario_manager).to receive(:configure_scenario_no_gemspec)
-        scenario_manager.send(:configure_scenario_inner)
+      context "with Gemfile" do
+        before do
+          scenario_manager.instance_variable_set(:@with_gemfile, true)
+        end
+
+        it "sets scenario to :gemfile" do
+          scenario_manager.configure_scenario
+          expect(scenario_manager.instance_variable_get(:@scenario)).to eq(:gemfile)
+        end
       end
     end
 
-    context "when @gs_length is 1" do
+    context "when one gemspec is present" do
       before do
         scenario_manager.instance_variable_set(:@gs_length, 1)
       end
 
-      context "and @with_gemfile is true" do
+      context "without Gemfile" do
         before do
-          scenario_manager.instance_variable_set(:@with_gemfile, true)
-          scenario_manager.send(:configure_scenario_inner)
+          scenario_manager.instance_variable_set(:@with_gemfile, false)
         end
 
-        it "sets @scenario to :gemspec_and_gemfile" do
-          expect(scenario_manager.instance_variable_get(:@scenario)).to eq(:gemspec_and_gemfile)
+        it "sets scenario to :gemspec" do
+          scenario_manager.configure_scenario
+          expect(scenario_manager.instance_variable_get(:@scenario)).to eq(:gemspec)
         end
       end
 
-      context "and @with_gemfile is false" do
+      context "with Gemfile" do
         before do
-          scenario_manager.instance_variable_set(:@with_gemfile, false)
-          scenario_manager.send(:configure_scenario_inner)
+          scenario_manager.instance_variable_set(:@with_gemfile, true)
         end
 
-        it "sets @scenario to :gemspec" do
-          expect(scenario_manager.instance_variable_get(:@scenario)).to eq(:gemspec)
+        it "sets scenario to :gemspec_and_gemfile" do
+          scenario_manager.configure_scenario
+          expect(scenario_manager.instance_variable_get(:@scenario)).to eq(:gemspec_and_gemfile)
         end
       end
     end
 
-    context "when @gs_length is greater than 1" do
+    context "when multiple gemspecs are present" do
       before do
         scenario_manager.instance_variable_set(:@gs_length, 2)
       end
 
-      it "raises a Tebako::Error" do
-        expect do
-          scenario_manager.send(:configure_scenario_inner)
-        end.to raise_error(Tebako::Error,
-                           "Multiple Ruby gemspecs found in #{scenario_manager.instance_variable_get(:@fs_root)}")
+      it "raises error" do
+        expect { scenario_manager.configure_scenario }.to raise_error(
+          Tebako::Error,
+          "Multiple Ruby gemspecs found in #{fs_root}"
+        )
       end
     end
   end
@@ -174,28 +176,6 @@
     end
   end
 
-  describe "#exe_suffix" do
-    context "when running on Windows" do
-      before do
-        stub_const("RUBY_PLATFORM", "msys")
-      end
-
-      it "returns .exe" do
-        expect(scenario_manager.exe_suffix).to eq(".exe")
-      end
-    end
-
-    context "when not running on Windows" do
-      before do
-        stub_const("RUBY_PLATFORM", "linux")
-      end
-
-      it "returns an empty string" do
-        expect(scenario_manager.exe_suffix).to eq("")
-      end
-    end
-  end
-
   describe "#lookup_files" do
     let(:tmp_root) { Dir.mktmpdir }
     let(:scenario_manager) { described_class.new(tmp_root, "dummy_entry.rb") }
diff --git a/tebako.gemspec b/tebako.gemspec
index 0184985c..b5e525f1 100644
--- a/tebako.gemspec
+++ b/tebako.gemspec
@@ -63,8 +63,10 @@ Gem::Specification.new do |spec|
   spec.add_dependency "thor", "~> 1.2"
   spec.add_dependency "yaml", "~> 0.2.1"
 
+  spec.add_development_dependency "debug"
   spec.add_development_dependency "hoe"
   spec.add_development_dependency "minitest"
+  spec.add_development_dependency "rdbg"
   spec.add_development_dependency "rspec", "~> 3.2"
   spec.add_development_dependency "rubocop", "~> 1.52"
   spec.add_development_dependency "rubocop-rubycw"