diff --git a/examples/temp_sensor/rakefile_helper.rb b/examples/temp_sensor/rakefile_helper.rb
index d1dfcc9..55bea2d 100644
--- a/examples/temp_sensor/rakefile_helper.rb
+++ b/examples/temp_sensor/rakefile_helper.rb
@@ -24,30 +24,24 @@ module RakefileHelpers
 
   def load_configuration(config_file)
     $cfg_file = config_file
-    $cfg = load_yaml(File.read("../../test/targets/#{$cfg_file}"))
     $proj = load_yaml(File.read('./project.yml'))
 
-    # Apply project-level paths, overriding the test-system paths in the target file
-    $cfg['compiler']['source_path']                 = $proj[:paths][:source].first
-    $cfg['compiler']['unit_tests_path']             = $proj[:paths][:test]
-    $cfg['compiler']['build_path']                  = $proj[:project][:build_root]
-    $cfg['compiler']['object_files']['destination'] = $proj[:project][:build_root]
-    $cfg['linker']['object_files']['path']          = $proj[:project][:build_root]
-    $cfg['linker']['bin_files']['destination']      = $proj[:project][:build_root]
+    unity_target = "../../vendor/unity/test/targets/#{$cfg_file}"
+    cmock_target = "../../test/targets/#{$cfg_file}"
 
-    # Merge includes: preserve any target-specific items (tool paths, local headers),
-    # then add project.yml paths (| deduplicates)
-    $cfg['compiler']['includes']['items'] = ($cfg['compiler']['includes']['items'] || []) | $proj[:paths][:include]
-
-    # Merge defines: target-specific first, then project common defines
-    $cfg['compiler']['defines']['items'] ||= []
-    $cfg['compiler']['defines']['items'] |= $proj[:defines][:common]
+    if File.exist?(unity_target)
+      $unity_cfg = load_yaml(File.read(unity_target))
+      $cmock_cfg = File.exist?(cmock_target) ? load_yaml(File.read(cmock_target)) : {}
+    else
+      $unity_cfg = load_yaml(File.read(cmock_target))
+      $cmock_cfg = {}
+    end
 
     $colour_output = $proj[:project][:colour]
   end
 
   def configure_clean
-    CLEAN.include("#{$cfg['compiler']['build_path']}*.*") unless $cfg['compiler']['build_path'].nil?
+    CLEAN.include("#{$proj[:project][:build_root]}*.*")
   end
 
   def configure_toolchain(config_file = DEFAULT_CONFIG_FILE)
@@ -57,15 +51,13 @@ module RakefileHelpers
   end
 
   def unit_test_files
-    path = $cfg['compiler']['unit_tests_path'] + "Test*#{C_EXTENSION}"
+    path = $proj[:paths][:test] + "Test*#{C_EXTENSION}"
     path.tr!('\\', '/')
     FileList.new(path)
   end
 
   def local_include_dirs
-    include_dirs = $cfg['compiler']['includes']['items'].dup
-    include_dirs.delete_if { |dir| dir.is_a?(Array) }
-    include_dirs
+    $proj[:paths][:include].reject { |dir| dir.is_a?(Array) }
   end
 
   def extract_headers(filename)
@@ -73,9 +65,7 @@ module RakefileHelpers
     lines = File.readlines(filename)
     lines.each do |line|
       m = line.match(/^\s*#include\s+"\s*(.+\.[hH])\s*"/)
-      unless m.nil?
-        includes << m[1]
-      end
+      includes << m[1] unless m.nil?
     end
     includes
   end
@@ -83,9 +73,7 @@ module RakefileHelpers
   def find_source_file(header, paths)
     paths.each do |dir|
       src_file = dir + header.ext(C_EXTENSION)
-      if File.exist?(src_file)
-        return src_file
-      end
+      return src_file if File.exist?(src_file)
     end
     nil
   end
@@ -103,79 +91,85 @@ module RakefileHelpers
     end
   end
 
-  def squash(prefix, items)
-    result = ''
-    items.each { |item| result += " #{prefix}#{tackit(item)}" }
-    result
+  # All defines: project common + Unity target + CMock overlay + any extras
+  def all_defines(extra = [])
+    (($proj[:defines][:common] || []) +
+     ($unity_cfg[:defines][:test] || []) +
+     (($cmock_cfg[:defines] || {})[:test] || []) +
+     extra).uniq
   end
 
-  def build_compiler_fields
-    command = tackit($cfg['compiler']['path'])
-    defines = if $cfg['compiler']['defines']['items'].nil?
-                ''
-              else
-                squash($cfg['compiler']['defines']['prefix'], $cfg['compiler']['defines']['items'])
-              end
-    options = squash('', $cfg['compiler']['options'])
-    includes = squash($cfg['compiler']['includes']['prefix'], $cfg['compiler']['includes']['items'])
-    includes = includes.gsub(/\\ /, ' ').gsub(/\\"/, '"').gsub(/\\$/, '') # Remove trailing slashes (for IAR)
-    { :command => command, :defines => defines, :options => options, :includes => includes }
+  # Toolchain-specific include paths: Array items in Unity's :paths: :test:
+  def toolchain_include_paths
+    if $unity_cfg[:paths] && $unity_cfg[:paths][:test]
+      $unity_cfg[:paths][:test]
+    else
+      []
+    end
   end
 
-  def compile(file, _defines = [])
-    compiler = build_compiler_fields
-    cmd_str  = "#{compiler[:command]}#{compiler[:defines]}#{compiler[:options]}#{compiler[:includes]} #{file} " \
-               "#{$cfg['compiler']['object_files']['prefix']}#{$cfg['compiler']['object_files']['destination']}"
-    obj_file = "#{File.basename(file, C_EXTENSION)}#{$cfg['compiler']['object_files']['extension']}"
-    execute(cmd_str + obj_file)
-    obj_file
+  # Resolve Unity's argument template tokens into a flat argument string.
+  def build_argument_list(raw_args, toolchain_paths, project_paths, defines, input, output)
+    result = []
+    raw_args.each do |arg|
+      if arg.is_a?(Array)
+        result << arg.join
+      elsif arg.include?('COLLECTION_PATHS_TEST_TOOLCHAIN_INCLUDE')
+        toolchain_paths.each { |p| result << "-I\"#{p.is_a?(Array) ? p.join : p}\"" }
+      elsif arg.include?('COLLECTION_PATHS_TEST_SUPPORT_SOURCE_INCLUDE_VENDOR')
+        project_paths.each { |p| result << "-I\"#{p}\"" }
+      elsif arg.include?('COLLECTION_DEFINES_TEST_AND_VENDOR')
+        defines.each { |d| result << "-D#{d}" }
+      else
+        result << arg.gsub('${1}', input.to_s).gsub('${2}', output.to_s)
+      end
+    end
+    result.join(' ')
   end
 
-  def build_linker_fields
-    command = tackit($cfg['linker']['path'])
-    options = if $cfg['linker']['options'].nil?
-                ''
-              else
-                squash('', $cfg['linker']['options'])
-              end
-    includes = if $cfg['linker']['includes'].nil? || $cfg['linker']['includes']['items'].nil?
-                 ''
-               else
-                 squash($cfg['linker']['includes']['prefix'], $cfg['linker']['includes']['items'])
-               end
-    includes = includes.gsub(/\\ /, ' ').gsub(/\\"/, '"').gsub(/\\$/, '') # Remove trailing slashes (for IAR)
-    { :command => command, :options => options, :includes => includes }
+  def compile(file, extra_defines = [])
+    tool       = $unity_cfg[:tools][:test_compiler]
+    ext        = $unity_cfg[:extension][:object]
+    build_root = $proj[:project][:build_root]
+    obj_file   = build_root + File.basename(file, C_EXTENSION) + ext
+
+    cmd_str = "#{tackit(tool[:executable])} #{
+              build_argument_list(tool[:arguments],
+                                  toolchain_include_paths,
+                                  $proj[:paths][:include],
+                                  all_defines(extra_defines),
+                                  file, obj_file)}"
+    execute(cmd_str)
+    File.basename(obj_file)
   end
 
   def link_it(exe_name, obj_list)
-    linker = build_linker_fields
-    cmd_str = "#{linker[:command]}#{linker[:includes]} " \
-              "#{(obj_list.map { |obj| "#{$cfg['linker']['object_files']['path']}#{obj} " }).join}" \
-              "#{$cfg['linker']['bin_files']['prefix']} " \
-              "#{$cfg['linker']['bin_files']['destination']}" \
-              "#{exe_name}#{$cfg['linker']['bin_files']['extension']} #{linker[:options]}"
+    tool       = $unity_cfg[:tools][:test_linker]
+    ext        = $unity_cfg[:extension][:executable]
+    build_root = $proj[:project][:build_root]
+
+    input_files = obj_list.uniq.map { |obj| build_root + obj }.join(' ')
+    output_file = build_root + exe_name + ext
+
+    cmd_str = "#{tackit(tool[:executable])} #{build_argument_list(tool[:arguments], [], [], [], input_files, output_file)}"
     execute(cmd_str)
   end
 
   def build_simulator_fields
-    return nil if $cfg['simulator'].nil?
+    return nil unless $unity_cfg[:tools][:test_fixture]
 
-    command = if $cfg['simulator']['path'].nil?
-                ''
-              else
-                "#{tackit($cfg['simulator']['path'])} "
-              end
-    pre_support = if $cfg['simulator']['pre_support'].nil?
-                    ''
-                  else
-                    squash('', $cfg['simulator']['pre_support'])
-                  end
-    post_support = if $cfg['simulator']['post_support'].nil?
-                     ''
-                   else
-                     squash('', $cfg['simulator']['post_support'])
-                   end
-    { :command => command, :pre_support => pre_support, :post_support => post_support }
+    tool       = $unity_cfg[:tools][:test_fixture]
+    executable = tackit(tool[:executable])
+    raw_args   = tool[:arguments] || []
+    idx        = raw_args.index('${1}')
+    if idx
+      pre  = raw_args[0...idx].map { |a| a.is_a?(Array) ? a.join : a }.join(' ')
+      post = raw_args[(idx + 1)..].map { |a| a.is_a?(Array) ? a.join : a }.join(' ')
+    else
+      pre  = ''
+      post = raw_args.map { |a| a.is_a?(Array) ? a.join : a }.join(' ')
+    end
+    { command: "#{executable} ", pre_support: pre, post_support: post }
   end
 
   def execute(command_string, verbose = true, ok_to_fail = false)
@@ -192,7 +186,7 @@ module RakefileHelpers
   def report_summary
     summary = UnityTestSummary.new
     summary.root = HERE
-    results_glob = "#{$cfg['compiler']['build_path']}*.test*"
+    results_glob = "#{$proj[:project][:build_root]}*.test*"
     results_glob.tr!('\\', '/')
     results = Dir[results_glob]
     summary.targets = results
@@ -203,17 +197,13 @@ module RakefileHelpers
   def run_tests(test_files)
     report 'Running system tests...'
 
-    # Tack on TEST define for compiling unit tests
     load_configuration($cfg_file)
-    test_defines = ['TEST']
-    $cfg['compiler']['defines']['items'] = [] if $cfg['compiler']['defines']['items'].nil?
-    $cfg['compiler']['defines']['items'] << 'TEST'
 
     include_dirs = local_include_dirs
 
     # Build and execute each unit test
     test_files.each do |test|
-      # Detect dependencies and build required required modules
+      # Detect dependencies and build required modules
       header_list = (extract_headers(test) + ['cmock.h'] + [($proj[:cmock] || {})[:unity_helper_path]]).compact.uniq
       header_list.each do |header|
         # create mocks if needed
@@ -221,53 +211,42 @@ module RakefileHelpers
 
         require '../../lib/cmock'
         @cmock ||= CMock.new($proj[:cmock])
-        @cmock.setup_mocks([$cfg['compiler']['source_path'] + header.gsub('Mock', '')])
+        @cmock.setup_mocks([$proj[:paths][:source].first + header.gsub('Mock', '')])
       end
 
-      # compile all mocks
+      # compile all mocks and dependencies
       obj_list = []
       header_list.each do |header|
-        # compile source file header if it exists
         src_file = find_source_file(header, include_dirs)
-        unless src_file.nil?
-          obj_list << compile(src_file, test_defines)
-        end
+        obj_list << compile(src_file, ['TEST']) unless src_file.nil?
       end
 
-      # Build the test runner (generate if configured to do so)
-      test_base = File.basename(test, C_EXTENSION)
+      # Build the test runner
+      test_base   = File.basename(test, C_EXTENSION)
       runner_name = "#{test_base}_Runner.c"
-      if $cfg['compiler']['runner_path'].nil?
-        runner_path = "#{$cfg['compiler']['build_path']}#{runner_name}"
-        test_gen = UnityTestRunnerGenerator.new($cfg)
-        test_gen.run(test, runner_path)
-      else
-        runner_path = $cfg['compiler']['runner_path'] + runner_name
-      end
+      runner_path = "#{$proj[:project][:build_root]}#{runner_name}"
+      UnityTestRunnerGenerator.new({}).run(test, runner_path)
 
-      obj_list << compile(runner_path, test_defines)
+      obj_list << compile(runner_path, ['TEST'])
 
       # Build the test module
-      obj_list << compile(test, test_defines)
+      obj_list << compile(test, ['TEST'])
 
       # Link the test executable
       link_it(test_base, obj_list)
 
       # Execute unit test and generate results file
-      simulator = build_simulator_fields
-      executable = $cfg['linker']['bin_files']['destination'] + test_base + $cfg['linker']['bin_files']['extension']
+      simulator  = build_simulator_fields
+      build_root = $proj[:project][:build_root]
+      executable = build_root + test_base + $unity_cfg[:extension][:executable]
       cmd_str = if simulator.nil?
                   executable
                 else
                   "#{simulator[:command]} #{simulator[:pre_support]} #{executable} #{simulator[:post_support]}"
                 end
       output = execute(cmd_str, true)
-      test_results = $cfg['compiler']['build_path'] + test_base
-      test_results += if output.match(/OK$/m).nil?
-                        '.testfail'
-                      else
-                        '.testpass'
-                      end
+      test_results = build_root + test_base
+      test_results += output.match(/OK$/m).nil? ? '.testfail' : '.testpass'
       File.open(test_results, 'w') { |f| f.print output }
     end
   end
@@ -277,22 +256,19 @@ module RakefileHelpers
 
     obj_list = []
     load_configuration($cfg_file)
-    main_path = $cfg['compiler']['source_path'] + main + C_EXTENSION
+    main_path = $proj[:paths][:source].first + main + C_EXTENSION
 
-    # Detect dependencies and build required required modules
+    # Detect dependencies and build required modules
     include_dirs = local_include_dirs
     extract_headers(main_path).each do |header|
       src_file = find_source_file(header, include_dirs)
-      unless src_file.nil?
-        obj_list << compile(src_file)
-      end
+      obj_list << compile(src_file) unless src_file.nil?
     end
 
     # Build the main source file
-    main_base = File.basename(main_path, C_EXTENSION)
     obj_list << compile(main_path)
 
     # Create the executable
-    link_it(main_base, obj_list)
+    link_it(File.basename(main_path, C_EXTENSION), obj_list)
   end
 end
diff --git a/test/project.yml b/test/project.yml
index 83c3aa1..9b1123e 100644
--- a/test/project.yml
+++ b/test/project.yml
@@ -30,5 +30,4 @@
 :defines:
   :common:
     - CMOCK
-    - UNITY_SUPPORT_64
 
diff --git a/test/rakefile b/test/rakefile
index 1ccf5e4..c48f1d2 100644
--- a/test/rakefile
+++ b/test/rakefile
@@ -14,7 +14,7 @@ require './rakefile_helper'
 
 include RakefileHelpers
 
-DEFAULT_CONFIG_FILE = 'gcc.yml'
+DEFAULT_CONFIG_FILE = 'gcc_64.yml'
 CMOCK_TEST_ROOT = File.expand_path(File.dirname(__FILE__))
 
 SYSTEM_TEST_SUPPORT_DIRS = [
@@ -30,7 +30,6 @@ end
 
 task :prep_system_tests => SYSTEM_TEST_SUPPORT_DIRS
 
-configure_clean
 configure_toolchain(DEFAULT_CONFIG_FILE)
 
 task :default => [:test]
@@ -67,7 +66,7 @@ namespace :test do
 
   desc "Run C Unit Tests"
   task :c => [:prep_system_tests] do
-    unless ($cfg['unsupported'].include? "C")
+    unless (unsupported_tests.include? "C")
       build_and_test_c_files
     end
   end
@@ -75,9 +74,9 @@ namespace :test do
   desc "Run System Tests"
   task :system => [:clobber, :prep_system_tests] do
     #get a list of all system tests, removing unsupported tests for this compiler
-    sys_unsupported  = $cfg['unsupported'].map {|a| 'system/test_interactions/'+a+'.yml'}
+    sys_unsupported  = unsupported_tests.map {|a| 'system/test_interactions/'+a+'.yml'}
     sys_tests_to_run = FileList['system/test_interactions/*.yml'] - sys_unsupported
-    compile_unsupported  = $cfg['unsupported'].map {|a| SYSTEST_COMPILE_MOCKABLES_PATH+a+'.h'}
+    compile_unsupported  = unsupported_tests.map {|a| SYSTEST_COMPILE_MOCKABLES_PATH+a+'.h'}
     compile_tests_to_run = FileList[SYSTEST_COMPILE_MOCKABLES_PATH + '*.h'] - compile_unsupported
     unless (sys_unsupported.empty? and compile_unsupported.empty?)
       report "\nIgnoring these system tests..."
@@ -134,7 +133,7 @@ namespace :style do
 
   desc "Attempt to Autocorrect style"
   task :auto  => ['style:clean'] do
-    report execute("rubocop ../lib ../examples ../config ../scripts --auto-correct --config ../vendor/unity/test/.rubocop.yml", true)
+    report execute("rubocop ../lib ../examples ../config ../scripts --autocorrect --config ../vendor/unity/test/.rubocop.yml", true)
     report "Autocorrected What We Could."
   end
 
diff --git a/test/rakefile_helper.rb b/test/rakefile_helper.rb
index 1eb93f5..7f7723e 100644
--- a/test/rakefile_helper.rb
+++ b/test/rakefile_helper.rb
@@ -31,30 +31,26 @@ module RakefileHelpers
 
   def load_configuration(config_file)
     $cfg_file = config_file
-    $cfg = load_yaml('./targets/' + $cfg_file)
     $proj = load_yaml('./project.yml')
 
-    # Apply project-level paths, overriding any hardcoded paths in the target file
-    $cfg['compiler']['source_path']                 = $proj[:paths][:source].first
-    $cfg['compiler']['build_path']                  = $proj[:project][:build_root]
-    $cfg['compiler']['object_files']['destination'] = $proj[:project][:build_root]
-    $cfg['linker']['object_files']['path']          = $proj[:project][:build_root]
-    $cfg['linker']['bin_files']['destination']      = $proj[:project][:build_root]
+    unity_target = "../vendor/unity/test/targets/#{$cfg_file}"
+    cmock_target = "./targets/#{$cfg_file}"
 
-    # Merge includes: preserve any target-specific items (tool paths, local headers),
-    # then add project.yml paths (| deduplicates)
-    $cfg['compiler']['includes']['items'] = ($cfg['compiler']['includes']['items'] || []) | $proj[:paths][:include]
-
-    # Merge defines: target-specific first, then project common defines
-    $cfg['compiler']['defines']['items'] ||= []
-    $cfg['compiler']['defines']['items'] |= $proj[:defines][:common]
+    if File.exist?(unity_target)
+      # Load Unity base target, then CMock overlay (unsupported list, extra defines)
+      $unity_cfg = load_yaml(unity_target)
+      $cmock_cfg = File.exist?(cmock_target) ? load_yaml(cmock_target) : {}
+    else
+      # CMock-only target (no Unity equivalent); it uses Unity format directly
+      $unity_cfg = load_yaml(cmock_target)
+      $cmock_cfg = {}
+    end
 
     $colour_output = $proj[:project][:colour]
   end
 
   def configure_clean
-    CLEAN.include(SYSTEST_GENERATED_FILES_PATH + '*.*')
-    CLEAN.include(SYSTEST_BUILD_FILES_PATH + '*.*')
+    CLEAN.include($proj[:project][:build_root] + '*.*')
   end
 
   def configure_toolchain(config_file)
@@ -63,9 +59,7 @@ module RakefileHelpers
   end
 
   def get_local_include_dirs
-    include_dirs = $cfg['compiler']['includes']['items'].dup
-    include_dirs.delete_if {|dir| dir.is_a?(Array)}
-    return include_dirs
+    $proj[:paths][:include].reject { |dir| dir.is_a?(Array) }
   end
 
   def extract_headers(filename)
@@ -73,100 +67,123 @@ module RakefileHelpers
     lines = File.readlines(filename)
     lines.each do |line|
       m = line.match(/^\s*#include\s+\"\s*(.+\.[hH])\s*\"/)
-      if not m.nil?
-        includes << m[1]
-      end
+      includes << m[1] unless m.nil?
     end
-    includes << File.basename(filename,".c").slice(5,256) + "_unity_helper.h"
+    includes << File.basename(filename, ".c").slice(5, 256) + "_unity_helper.h"
     return includes
   end
 
   def find_source_file(header, paths)
     paths.each do |dir|
       src_file = dir + header.ext(C_EXTENSION)
-      if (File.exist?(src_file))
-        return src_file
+      return src_file if File.exist?(src_file)
+    end
+    nil
+  end
+
+  def tackit(strings)
+    case strings
+    when Array
+      "\"#{strings.join}\""
+    when /^-/
+      strings
+    when /\s/
+      "\"#{strings}\""
+    else
+      strings
+    end
+  end
+
+  # All defines: project common + Unity target + CMock overlay + any extras
+  def all_defines(extra = [])
+    (($proj[:defines][:common] || []) +
+     ($unity_cfg[:defines][:test] || []) +
+     (($cmock_cfg[:defines] || {})[:test] || []) +
+     extra).uniq
+  end
+
+  # Toolchain-specific include paths: Array items in Unity's :paths: :test:
+  # (e.g., IAR compiler include directories encoded as path-concatenation arrays)
+  def toolchain_include_paths
+    ($unity_cfg[:paths][:test] || []).select { |p| p.is_a?(Array) }
+  end
+
+  # Returns the unsupported test list, regardless of whether it came from
+  # a CMock overlay or a CMock-only target file.
+  def unsupported_tests
+    $cmock_cfg[:unsupported] || $unity_cfg[:unsupported] || []
+  end
+
+  # Resolve Unity's argument template tokens and produce a flat argument string.
+  #   COLLECTION_PATHS_TEST_TOOLCHAIN_INCLUDE  → -I per toolchain path (Arrays from :paths: :test:)
+  #   COLLECTION_PATHS_TEST_SUPPORT_SOURCE_INCLUDE_VENDOR → -I per project include path
+  #   COLLECTION_DEFINES_TEST_AND_VENDOR       → -D per define
+  #   ${1}  → input file(s)
+  #   ${2}  → output file
+  def build_argument_list(raw_args, toolchain_paths, project_paths, defines, input, output)
+    result = []
+    raw_args.each do |arg|
+      if arg.is_a?(Array)
+        result << arg.join
+      elsif arg.include?('COLLECTION_PATHS_TEST_TOOLCHAIN_INCLUDE')
+        toolchain_paths.each { |p| result << "-I\"#{p.is_a?(Array) ? p.join : p}\"" }
+      elsif arg.include?('COLLECTION_PATHS_TEST_SUPPORT_SOURCE_INCLUDE_VENDOR')
+        project_paths.each { |p| result << "-I\"#{p}\"" }
+      elsif arg.include?('COLLECTION_DEFINES_TEST_AND_VENDOR')
+        defines.each { |d| result << "-D#{d}" }
+      else
+        result << arg.gsub('${1}', input.to_s).gsub('${2}', output.to_s)
       end
     end
-    return nil
+    result.join(' ')
   end
 
-  def squash(prefix, items)
-    result = ''
-    items.each { |item| result += " #{prefix}#{tackit(item)}" }
-    return result
-  end
+  def compile(file, extra_defines = [])
+    tool       = $unity_cfg[:tools][:test_compiler]
+    ext        = $unity_cfg[:extension][:object]
+    build_root = $proj[:project][:build_root]
+    obj_file   = build_root + File.basename(file, C_EXTENSION) + ext
 
-  def build_compiler_fields
-    command  = tackit($cfg['compiler']['path'])
-    if $cfg['compiler']['defines']['items'].nil?
-      defines  = ''
-    else
-      defines  = squash($cfg['compiler']['defines']['prefix'], $cfg['compiler']['defines']['items'])
-    end
-    options  = squash('', $cfg['compiler']['options'])
-    includes = squash($cfg['compiler']['includes']['prefix'], $cfg['compiler']['includes']['items'])
-    includes = includes.gsub(/\\ /, ' ').gsub(/\\\"/, '"').gsub(/\\$/, '') # Remove trailing slashes (for IAR)
-    return {:command => command, :defines => defines, :options => options, :includes => includes}
-  end
-
-  def compile(file, defines=[])
-    compiler = build_compiler_fields
-    cmd_str = "#{compiler[:command]}#{compiler[:defines]}#{defines.inject(''){|all, a| ' -D'+a+all }}#{compiler[:options]}#{compiler[:includes]} #{file} " +
-      "#{$cfg['compiler']['object_files']['prefix']}#{$cfg['compiler']['object_files']['destination']}"
-    obj_file = "#{File.basename(file, C_EXTENSION)}#{$cfg['compiler']['object_files']['extension']}"
-    execute(cmd_str + obj_file)
-    return obj_file
-  end
-
-  def build_linker_fields
-    command  = tackit($cfg['linker']['path'])
-    if $cfg['linker']['options'].nil?
-      options  = ''
-    else
-      options  = squash('', $cfg['linker']['options'])
-    end
-    if ($cfg['linker']['includes'].nil? || $cfg['linker']['includes']['items'].nil?)
-      includes = ''
-    else
-      includes = squash($cfg['linker']['includes']['prefix'], $cfg['linker']['includes']['items'])
-    end
-    includes = includes.gsub(/\\ /, ' ').gsub(/\\\"/, '"').gsub(/\\$/, '') # Remove trailing slashes (for IAR)
-    return {:command => command, :options => options, :includes => includes}
+    cmd_str = tackit(tool[:executable]) + ' ' +
+              build_argument_list(tool[:arguments],
+                                  toolchain_include_paths,
+                                  $proj[:paths][:include],
+                                  all_defines(extra_defines),
+                                  file, obj_file)
+    execute(cmd_str)
+    File.basename(obj_file)
   end
 
   def link_it(exe_name, obj_list)
-    linker = build_linker_fields
-    cmd_str = "#{linker[:command]}#{linker[:options]}#{linker[:includes]} " +
-      (obj_list.map{|obj|"#{$cfg['linker']['object_files']['path']}#{obj} "}).uniq.join +
-      $cfg['linker']['bin_files']['prefix'] + ' ' +
-      $cfg['linker']['bin_files']['destination'] +
-      exe_name + $cfg['linker']['bin_files']['extension']
+    tool       = $unity_cfg[:tools][:test_linker]
+    ext        = $unity_cfg[:extension][:executable]
+    build_root = $proj[:project][:build_root]
+
+    input_files = obj_list.uniq.map { |obj| build_root + obj }.join(' ')
+    output_file = build_root + exe_name + ext
+
+    cmd_str = tackit(tool[:executable]) + ' ' +
+              build_argument_list(tool[:arguments], [], [], [], input_files, output_file)
     execute(cmd_str)
   end
 
   def build_simulator_fields
-    return nil if $cfg['simulator'].nil?
-    if $cfg['simulator']['path'].nil?
-      command = ''
+    return nil unless $unity_cfg[:tools][:test_fixture]
+    tool      = $unity_cfg[:tools][:test_fixture]
+    executable = tackit(tool[:executable])
+    raw_args   = tool[:arguments] || []
+    idx        = raw_args.index('${1}')
+    if idx
+      pre  = raw_args[0...idx].map { |a| a.is_a?(Array) ? a.join : a }.join(' ')
+      post = raw_args[(idx + 1)..].map { |a| a.is_a?(Array) ? a.join : a }.join(' ')
     else
-      command = (tackit($cfg['simulator']['path']) + ' ')
+      pre  = ''
+      post = raw_args.map { |a| a.is_a?(Array) ? a.join : a }.join(' ')
     end
-    if $cfg['simulator']['pre_support'].nil?
-      pre_support = ''
-    else
-      pre_support = squash('', $cfg['simulator']['pre_support'])
-    end
-    if $cfg['simulator']['post_support'].nil?
-      post_support = ''
-    else
-      post_support = squash('', $cfg['simulator']['post_support'])
-    end
-    return {:command => command, :pre_support => pre_support, :post_support => post_support}
+    { command: "#{executable} ", pre_support: pre, post_support: post }
   end
 
   def execute(command_string, verbose=true, raise_on_failure=true)
-    #report command_string
     output = `#{command_string}`.chomp
     report(output) if (verbose && !output.nil? && (output.length > 0))
     if ($?.exitstatus != 0) and (raise_on_failure)
@@ -175,19 +192,6 @@ module RakefileHelpers
     return output
   end
 
-  def tackit(strings)
-    case(strings)
-      when Array
-        "\"#{strings.join}\""
-      when /^-/
-        strings
-      when /\s/
-        "\"#{strings}\""
-      else
-        strings
-    end
-  end
-
   def run_astyle(style_what)
     report "Styling C Code..."
     command = "AStyle " \
@@ -203,7 +207,7 @@ module RakefileHelpers
   def report_summary
     summary = UnityTestSummary.new
     summary.root = File.expand_path(File.dirname(__FILE__)) + '/'
-    results_glob = "#{$cfg['compiler']['build_path']}*.test*"
+    results_glob = "#{$proj[:project][:build_root]}*.test*"
     results_glob.gsub!(/\\/, '/')
     results = Dir[results_glob]
     summary.targets = results
@@ -218,7 +222,6 @@ module RakefileHelpers
     test_files = FileList.new(SYSTEST_GENERATED_FILES_PATH + 'test*.c')
 
     load_configuration($cfg_file)
-    $cfg['compiler']['defines']['items'] = [] if $cfg['compiler']['defines']['items'].nil?
 
     include_dirs = get_local_include_dirs
 
@@ -232,25 +235,23 @@ module RakefileHelpers
 
       report "Executing system tests in #{File.basename(test)}..."
 
-      # Detect dependencies and build required required modules
+      # Detect dependencies and build required modules
       extract_headers(test).each do |header|
 
         # Generate any needed mocks
-        if header =~ /^mock_(.*)\.h/i
+        if header =~ /^mock_(.*)\.[hH]$/i
           module_name = $1
           cmock = CMock.new(SYSTEST_GENERATED_FILES_PATH + cmock_config)
-          cmock.setup_mocks("#{$cfg['compiler']['source_path']}#{module_name}.h")
+          cmock.setup_mocks("#{$proj[:paths][:source].first}#{module_name}.h")
         end
         # Compile corresponding source file if it exists
         src_file = find_source_file(header, include_dirs)
-        if !src_file.nil?
-          obj_list << compile(src_file)
-        end
+        obj_list << compile(src_file) unless src_file.nil?
       end
 
       # Generate and build the test suite runner
       runner_name = test_base + '_runner.c'
-      runner_path = $cfg['compiler']['source_path'] + runner_name
+      runner_path = $proj[:paths][:source].first + runner_name
       UnityTestRunnerGenerator.new(SYSTEST_GENERATED_FILES_PATH + cmock_config).run(test, runner_path)
       obj_list << compile(runner_path)
 
@@ -261,15 +262,17 @@ module RakefileHelpers
       link_it(test_base, obj_list)
 
       # Execute unit test and generate results file
-      simulator = build_simulator_fields
-      executable = $cfg['linker']['bin_files']['destination'] + test_base + $cfg['linker']['bin_files']['extension']
-      if simulator.nil?
-        cmd_str = executable
-      else
-        cmd_str = "#{simulator[:command]} #{simulator[:pre_support]} #{executable} #{simulator[:post_support]}"
-      end
+      simulator  = build_simulator_fields
+      ext        = $unity_cfg[:extension][:executable]
+      build_root = $proj[:project][:build_root]
+      executable = build_root + test_base + ext
+      cmd_str = if simulator.nil?
+                  executable
+                else
+                  "#{simulator[:command]} #{simulator[:pre_support]} #{executable} #{simulator[:post_support]}"
+                end
       output = execute(cmd_str, false, false)
-      test_results = $cfg['compiler']['build_path'] + test_base + RESULT_EXTENSION
+      test_results = build_root + test_base + RESULT_EXTENSION
       File.open(test_results, 'w') { |f| f.print output }
     end
 
@@ -284,10 +287,8 @@ module RakefileHelpers
 
       test_file    = 'test_' + File.basename(test_case).ext(C_EXTENSION)
       result_file  = test_file.ext(RESULT_EXTENSION)
-      test_results = File.readlines(SYSTEST_BUILD_FILES_PATH + result_file).reject {|line| line.size < 10 } # we're rejecting lines that are too short to be realistic, which handles line ending problems
+      test_results = File.readlines(SYSTEST_BUILD_FILES_PATH + result_file).reject {|line| line.size < 10 }
       tests.each_with_index do |test, index|
-        # compare test's intended pass/fail state with pass/fail state in actual results;
-        # if they don't match, the system test has failed
         this_failed = case(test[:pass])
           when :ignore
             (test_results[index] =~ /:IGNORE/).nil?
@@ -301,7 +302,6 @@ module RakefileHelpers
           test_results[index] =~ /test#{index+1}:(.+)/
           failure_messages << "#{test_file}:test#{index+1}:should #{test[:should]}:#{$1}"
         end
-        # some tests have additional requirements to check for (checking the actual output message)
         if (test[:verify_error]) and not (test_results[index] =~ /test#{index+1}:.*#{test[:verify_error]}/)
           total_failures += 1
           failure_messages << "#{test_file}:test#{index+1}:should #{test[:should]}:should have output matching '#{test[:verify_error]}' but was '#{test_results[index]}'"
@@ -318,13 +318,10 @@ module RakefileHelpers
 
     if (failure_messages.size > 0)
       report 'System test failures:'
-      failure_messages.each do |failure|
-        report failure
-      end
+      failure_messages.each { |failure| report failure }
     end
 
     report ''
-
     return total_failures
   end
 
@@ -349,9 +346,7 @@ module RakefileHelpers
 
   def run_system_test_compilations(mockables)
     load '../lib/cmock.rb'
-
     load_configuration($cfg_file)
-    $cfg['compiler']['defines']['items'] = [] if $cfg['compiler']['defines']['items'].nil?
 
     report "\n"
     report "------------------------------------\n"
@@ -367,9 +362,7 @@ module RakefileHelpers
 
   def run_system_test_profiles(mockables)
     load '../lib/cmock.rb'
-
     load_configuration($cfg_file)
-    $cfg['compiler']['defines']['items'] = [] if $cfg['compiler']['defines']['items'].nil?
 
     report "\n"
     report "--------------------------\n"
@@ -392,23 +385,21 @@ module RakefileHelpers
     report "----------------\n"
     report "UNIT TEST C CODE\n"
     report "----------------\n"
-    errors = false
+    ext        = $unity_cfg[:extension][:executable]
+    build_root = $proj[:project][:build_root]
     FileList.new("c/*.yml").each do |yaml_file|
       test = load_yaml(yaml_file)
       report "\nTesting #{yaml_file.sub('.yml','')}"
       report "(#{test[:options].join(', ')})"
       test[:files].each { |f| compile(f, test[:options]) }
-      obj_files = test[:files].map { |f| f.gsub!(/.*\//,'').gsub!(C_EXTENSION, $cfg['compiler']['object_files']['extension']) }
+      obj_files = test[:files].map { |f| f.gsub!(/.*\//,'').gsub!(C_EXTENSION, $unity_cfg[:extension][:object]) }
       link_it('TestCMockC', obj_files)
-      if $cfg['simulator'].nil?
-        execute($cfg['linker']['bin_files']['destination'] + 'TestCMockC' + $cfg['linker']['bin_files']['extension'])
+      simulator = build_simulator_fields
+      executable = build_root + 'TestCMockC' + ext
+      if simulator.nil?
+        execute(executable)
       else
-        execute(tackit($cfg['simulator']['path'].join) + ' ' +
-            $cfg['simulator']['pre_support'].map{|o| tackit(o)}.join(' ') + ' ' +
-            $cfg['linker']['bin_files']['destination'] +
-            'TestCMockC' +
-            $cfg['linker']['bin_files']['extension'] + ' ' +
-            $cfg['simulator']['post_support'].map{|o| tackit(o)}.join(' ') )
+        execute("#{simulator[:command]} #{simulator[:pre_support]} #{executable} #{simulator[:post_support]}")
       end
     end
   end
@@ -418,8 +409,8 @@ module RakefileHelpers
     report "-----------------\n"
     report "VALIDATE EXAMPLES\n"
     report "-----------------\n"
-    [ "cd #{File.join("..","examples","make_example")} && make clean && make setup && make test",
-      "cd #{File.join("..","examples","temp_sensor")} && rake ci"
+    [ "cd #{File.join("..", "examples", "make_example")} && make clean && make setup && make test",
+      "cd #{File.join("..", "examples", "temp_sensor")} && rake ci"
     ].each do |cmd|
       report "Testing '#{cmd}'"
       execute(cmd, verbose, raise_on_failure)
@@ -431,4 +422,3 @@ module RakefileHelpers
     exit(-1)
   end
 end
-
diff --git a/test/system/systest_generator.rb b/test/system/systest_generator.rb
index b82c52a..4568802 100644
--- a/test/system/systest_generator.rb
+++ b/test/system/systest_generator.rb
@@ -151,7 +151,7 @@ class SystemTestGenerator
 
     require 'cmock.rb'
     cmock = CMock.new(GENERATED_PATH + namix + 'cmock' + YAML_EXTENSION)
-    cmock.setup_skeletons("#{$cfg['compiler']['source_path']}#{name}.h")
+    cmock.setup_skeletons("#{$proj[:paths][:source].first}#{name}.h")
   end
 
   def write_header_file(filename, upcase_name, include_list=[])
diff --git a/test/targets/clang_strict.yml b/test/targets/clang_strict.yml
index f2c4d93..9063f8c 100644
--- a/test/targets/clang_strict.yml
+++ b/test/targets/clang_strict.yml
@@ -5,73 +5,13 @@
 #   SPDX-License-Identifier: MIT
 # =========================================================================
 
----
-compiler:
-  path: clang
-  options:
-    - '-c'
-    - '-Wall'
-    - '-Wextra'
-    - '-Werror'
-    #- '-Wcast-qual'
-    - '-Wconversion'
-    - '-Wtautological-compare'
-    #- '-Wtautological-pointer-compare'
-    - '-Wdisabled-optimization'
-    - '-Wformat=2'
-    - '-Winit-self'
-    - '-Winline'
-    - '-Winvalid-pch'
-    - '-Wmissing-declarations'
-    - '-Wmissing-include-dirs'
-    - '-Wmissing-prototypes'
-    - '-Wnonnull'
-    - '-Wpacked'
-    - '-Wpointer-arith'
-    - '-Wredundant-decls'
-    - '-Wswitch-default'
-    - '-Wstrict-aliasing=2'
-    - '-Wstrict-overflow=5'
-    - '-Wuninitialized'
-    - '-Wunused'
-    - '-Wunreachable-code'
-    - '-Wreturn-type'
-    - '-Wshadow'
-    - '-Wundef'
-    - '-Wwrite-strings'
-    - '-Wbad-function-cast'
-    - '-Wno-missing-prototypes' #we've been lazy about things like setUp and tearDown
-    - '-Wno-invalid-token-paste'
-    - '-fms-extensions'
-    - '-fno-omit-frame-pointer'
-    #- '-ffloat-store'
-    - '-fno-common'
-    - '-fstrict-aliasing'
-    - '-std=gnu99'
-    - '-pedantic'
-    - '-O0'
-  includes:
-    prefix: '-I'
-  defines:
-    prefix: '-D'
-    items:
-      - CMOCK
-      - 'UNITY_SUPPORT_64'
-      - 'UNITY_POINTER_WIDTH=64'
-  object_files:
-    prefix: '-o'
-    extension: '.o'
+# CMock overlay for vendor/unity/test/targets/clang_strict.yml
+# Only contains additions not present in the Unity base target.
 
-linker:
-  path: gcc
-  options:
-    - -lm
-  object_files:
-    extension: '.o'
-  bin_files:
-    prefix: '-o'
-    extension: '.exe'
+:defines:
+  :test:
+  - UNITY_POINTER_WIDTH=64
 
-unsupported:
+:unsupported:
   - out_of_memory
   - callingconv
diff --git a/test/targets/gcc.yml b/test/targets/gcc.yml
index 5eace39..93e518d 100644
--- a/test/targets/gcc.yml
+++ b/test/targets/gcc.yml
@@ -6,40 +6,40 @@
 # =========================================================================
 
 ---
-compiler:
-  path: gcc
-  options:
-    - '-c'
-    - '-Wall'
-    - '-Wextra'
-    - '-Wunused-parameter'
-    - '-Wno-address'
-    - '-Wno-invalid-token-paste'
-    - '-std=c99'
-    - '-pedantic'
-    - '-O0'
-  includes:
-    prefix: '-I'
-  defines:
-    prefix: '-D'
-    items:
-      - CMOCK
-      - 'UNITY_SUPPORT_64'
-  object_files:
-    prefix: '-o'
-    extension: '.o'
-
-linker:
-  path: gcc
-  options:
-    - -lm
-  object_files:
-    extension: '.o'
-  bin_files:
-    prefix: '-o'
-    extension: '.exe'
-
-unsupported:
+colour: true
+:tools:
+  :test_compiler:
+    :name: compiler
+    :executable: gcc
+    :arguments:
+    - "-c"
+    - "-Wall"
+    - "-Wextra"
+    - "-Wunused-parameter"
+    - "-Wno-address"
+    - "-Wno-invalid-token-paste"
+    - "-std=c99"
+    - "-pedantic"
+    - "-O0"
+    - '-I"$": COLLECTION_PATHS_TEST_TOOLCHAIN_INCLUDE'
+    - '-I"$": COLLECTION_PATHS_TEST_SUPPORT_SOURCE_INCLUDE_VENDOR'
+    - "-D$: COLLECTION_DEFINES_TEST_AND_VENDOR"
+    - "${1}"
+    - "-o ${2}"
+  :test_linker:
+    :name: linker
+    :executable: gcc
+    :arguments:
+    - "${1}"
+    - "-lm"
+    - "-o ${2}"
+:extension:
+  :object: ".o"
+  :executable: ".exe"
+:defines:
+  :test:
+  - UNITY_SUPPORT_64
+:unsupported:
   - out_of_memory
   - unity_64bit_support
   - callingconv
diff --git a/test/targets/gcc_64.yml b/test/targets/gcc_64.yml
index b1ff927..61a9de9 100644
--- a/test/targets/gcc_64.yml
+++ b/test/targets/gcc_64.yml
@@ -5,41 +5,13 @@
 #   SPDX-License-Identifier: MIT
 # =========================================================================
 
----
-compiler:
-  path: gcc
-  options:
-    - '-c'
-    - '-m64'
-    - '-Wall'
-    - '-Wunused-parameter'
-    - '-Wno-address'
-    - '-Wno-invalid-token-paste'
-    - '-std=c99'
-    - '-pedantic'
-  includes:
-    prefix: '-I'
-  defines:
-    prefix: '-D'
-    items:
-      - CMOCK
-      - 'UNITY_SUPPORT_64'
-      - 'UNITY_POINTER_WIDTH=64'
-  object_files:
-    prefix: '-o'
-    extension: '.o'
+# CMock overlay for vendor/unity/test/targets/gcc_64.yml
+# Only contains additions not present in the Unity base target.
 
-linker:
-  path: gcc
-  options:
-    - -lm
-    - '-m64'
-  object_files:
-    extension: '.o'
-  bin_files:
-    prefix: '-o'
-    extension: '.exe'
+:defines:
+  :test:
+  - UNITY_POINTER_WIDTH=64
 
-unsupported:
+:unsupported:
   - out_of_memory
   - callingconv
diff --git a/test/targets/gcc_tiny.yml b/test/targets/gcc_tiny.yml
index 3d10c89..a8064da 100644
--- a/test/targets/gcc_tiny.yml
+++ b/test/targets/gcc_tiny.yml
@@ -6,41 +6,41 @@
 # =========================================================================
 
 ---
-compiler:
-  path: gcc
-  options:
-    - '-c'
-    - '-Wall'
-    - '-Wextra'
-    - '-Wunused-parameter'
-    - '-Wno-address'
-    - '-Wno-invalid-token-paste'
-    - '-std=c99'
-    - '-pedantic'
-    - '-O0'
-  includes:
-    prefix: '-I'
-  defines:
-    prefix: '-D'
-    items:
-      - CMOCK
-      - 'CMOCK_MEM_STATIC'
-      - 'CMOCK_MEM_SIZE=1024'
-  object_files:
-    prefix: '-o'
-    extension: '.o'
-
-linker:
-  path: gcc
-  options:
-    - -lm
-  object_files:
-    extension: '.o'
-  bin_files:
-    prefix: '-o'
-    extension: '.exe'
-
-unsupported:
+colour: true
+:tools:
+  :test_compiler:
+    :name: compiler
+    :executable: gcc
+    :arguments:
+    - "-c"
+    - "-Wall"
+    - "-Wextra"
+    - "-Wunused-parameter"
+    - "-Wno-address"
+    - "-Wno-invalid-token-paste"
+    - "-std=c99"
+    - "-pedantic"
+    - "-O0"
+    - '-I"$": COLLECTION_PATHS_TEST_TOOLCHAIN_INCLUDE'
+    - '-I"$": COLLECTION_PATHS_TEST_SUPPORT_SOURCE_INCLUDE_VENDOR'
+    - "-D$: COLLECTION_DEFINES_TEST_AND_VENDOR"
+    - "${1}"
+    - "-o ${2}"
+  :test_linker:
+    :name: linker
+    :executable: gcc
+    :arguments:
+    - "${1}"
+    - "-lm"
+    - "-o ${2}"
+:extension:
+  :object: ".o"
+  :executable: ".exe"
+:defines:
+  :test:
+  - CMOCK_MEM_STATIC
+  - CMOCK_MEM_SIZE=1024
+:unsupported:
   - all_plugins_but_other_limits
   - all_plugins_coexist
   - array_and_pointer_handling
diff --git a/test/targets/iar_arm_v4.yml b/test/targets/iar_arm_v4.yml
index 76c1bd1..2b46d6b 100644
--- a/test/targets/iar_arm_v4.yml
+++ b/test/targets/iar_arm_v4.yml
@@ -5,90 +5,10 @@
 #   SPDX-License-Identifier: MIT
 # =========================================================================
 
-tools_root: &tools_root 'C:\Program Files\IAR Systems\Embedded Workbench 4.0\'
-compiler:
-  path:             [*tools_root, 'arm\bin\iccarm.exe']
-  options:
-    - --dlib_config
-    - [*tools_root, 'arm\lib\dl4tptinl8n.h']
-    - -z3
-    - --no_cse
-    - --no_unroll
-    - --no_inline
-    - --no_code_motion
-    - --no_tbaa
-    - --no_clustering
-    - --no_scheduling
-    - --debug
-    - --cpu_mode thumb
-    - --endian little
-    - --cpu ARM7TDMI
-    - --stack_align 4
-    - --interwork
-    - -e
-    - --silent
-    - --warnings_are_errors
-    - --fpu None
-    #We are supressing some warnings here because we test CMock against some questionable code to make sure it still works
-    - --diag_suppress Pa050
-    - --diag_suppress Pe191
-    - --diag_suppress=Pe494
-    - --diag_suppress=Pe083
-  includes:
-    prefix: '-I'
-    items:
-      - [*tools_root, 'arm\inc\']
-  defines:
-    prefix: '-D'
-    items:
-      - CMOCK
-  object_files:
-    prefix: '-o'
-    extension: '.r79'
+# CMock overlay for vendor/unity/test/targets/iar_arm_v4.yml
+# Only contains additions not present in the Unity base target.
 
-linker:
-  path: [*tools_root, 'common\bin\xlink.exe']
-  options:
-    - -rt
-    - [*tools_root, 'arm\lib\dl4tptinl8n.r79']
-    - -D_L_EXTMEM_START=0
-    - -D_L_EXTMEM_SIZE=0
-    - -D_L_HEAP_SIZE=120
-    - -D_L_STACK_SIZE=32
-    - -e_small_write=_formatted_write
-    - -s
-    - __program_start
-    - '-f iar\iar_v4\Resource\at91SAM7X256_FLASH.xcl'
-  includes:
-    prefix: '-I'
-    items:
-      - [*tools_root, 'arm\config\']
-      - [*tools_root, 'arm\lib\']
-  object_files:
-    extension: '.r79'
-  bin_files:
-    prefix: '-o'
-    extension: '.d79'
-
-simulator:
-  path: [*tools_root, 'common\bin\CSpyBat.exe']
-  pre_support:
-    - --silent
-    - [*tools_root, 'arm\bin\armproc.dll']
-    - [*tools_root, 'arm\bin\armsim.dll']
-  post_support:
-    - --plugin
-    - [*tools_root, 'arm\bin\armbat.dll']
-    - --macro
-    - 'iar\iar_v4\Resource\SAM7_SIM.mac'
-    - --backend
-    - -B
-    - -p
-    - [*tools_root, 'arm\config\ioat91sam7X256.ddf']
-    - -d
-    - sim
-
-unsupported:
+:unsupported:
   - out_of_memory
   - nonstandard_parsed_stuff_1
   - const
diff --git a/test/targets/iar_arm_v5.yml b/test/targets/iar_arm_v5.yml
index 0c57dea..443e5b2 100644
--- a/test/targets/iar_arm_v5.yml
+++ b/test/targets/iar_arm_v5.yml
@@ -5,79 +5,10 @@
 #   SPDX-License-Identifier: MIT
 # =========================================================================
 
-tools_root: &tools_root 'C:\Program Files\IAR Systems\Embedded Workbench 5.3\'
-compiler:
-  path:             [*tools_root, 'arm\bin\iccarm.exe']
-  options:
-    - --dlib_config
-    - [*tools_root, 'arm\inc\DLib_Config_Normal.h']
-    - --no_cse
-    - --no_unroll
-    - --no_inline
-    - --no_code_motion
-    - --no_tbaa
-    - --no_clustering
-    - --no_scheduling
-    - --debug
-    - --cpu_mode thumb
-    - --endian=little
-    - --cpu=ARM7TDMI
-    - --interwork
-    - --warnings_are_errors
-    - --fpu=None
-    - -e
-    - -On
-    #We are supressing some warnings here because we test CMock against some questionable code to make sure it still works
-    - --diag_suppress=Pa050
-    - --diag_suppress=Pe191
-    - --diag_suppress=Pe494
-    - --diag_suppress=Pe083
-  includes:
-    prefix: '-I'
-    items:
-      - [*tools_root, 'arm\inc\']
-      - '.\iar\iar_v5\incIAR\'
-  defines:
-    prefix: '-D'
-    items:
-      - CMOCK
-  object_files:
-    prefix: '-o'
-    extension: '.r79'
+# CMock overlay for vendor/unity/test/targets/iar_arm_v5.yml
+# Only contains additions not present in the Unity base target.
 
-linker:
-  path: [*tools_root, 'arm\bin\ilinkarm.exe']
-  options:
-    - --redirect _Printf=_PrintfLarge
-    - --redirect _Scanf=_ScanfSmall
-    - --semihosting
-    - --entry __iar_program_start
-    - --config iar\iar_v5\Resource\at91SAM7X256_RAM.icf
-  object_files:
-    extension: '.o'
-  bin_files:
-    prefix: '-o'
-    extension: '.out'
-
-simulator:
-  path: [*tools_root, 'common\bin\CSpyBat.exe']
-  pre_support:
-    - --silent
-    - [*tools_root, 'arm\bin\armproc.dll']
-    - [*tools_root, 'arm\bin\armsim.dll']
-  post_support:
-    - --plugin
-    - [*tools_root, 'arm\bin\armbat.dll']
-    - --macro
-    - 'iar\iar_v5\Resource\SAM7_SIM.mac'
-    - --backend
-    - -B
-    - -p
-    - [*tools_root, 'arm\config\debugger\Atmel\ioat91sam7X256.ddf']
-    - -d
-    - sim
-
-unsupported:
+:unsupported:
   - out_of_memory
   - nonstandard_parsed_stuff_1
   - const