diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index bf4f1597..3c64183f 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -67,7 +67,7 @@ add_subdirectory(core)
 include(app/gfx/gfx_library.cmake)
 include(app/net/net_library.cmake)
 include(app/gui/gui_library.cmake)
-include(app/core/core_library.cmake)
+# NOTE: app/core/core_library.cmake merged into app/app.cmake
 
 # Include test support library BEFORE yaze_editor so it can link against it
 # (yaze_editor needs TestManager for editor features)
diff --git a/src/app/app.cmake b/src/app/app.cmake
index ecf76291..98a4947d 100644
--- a/src/app/app.cmake
+++ b/src/app/app.cmake
@@ -1,4 +1,167 @@
-# This file defines the main `yaze` application executable.
+# ==============================================================================
+# Application Core Library (Platform, Controller, ROM, Services)
+# ==============================================================================
+# This library contains application-level core components:
+# - ROM management (app/rom.cc)
+# - Application controller (app/controller.cc)
+# - Window/platform management (app/platform/)
+# - gRPC services for AI automation (app/service/)
+#
+# Dependencies: yaze_core_lib (foundational), yaze_util, yaze_gfx, SDL2, ImGui
+# ==============================================================================
+
+set(
+  YAZE_APP_CORE_SRC
+  app/rom.cc
+  app/controller.cc
+  app/platform/window.cc
+)
+
+# Platform-specific sources
+if (WIN32 OR MINGW OR (UNIX AND NOT APPLE))
+  list(APPEND YAZE_APP_CORE_SRC
+    app/platform/font_loader.cc
+    app/platform/asset_loader.cc
+    app/platform/file_dialog_nfd.cc  # NFD file dialog for Windows/Linux
+  )
+endif()
+
+if(APPLE)
+    list(APPEND YAZE_APP_CORE_SRC
+      app/platform/font_loader.cc
+      app/platform/asset_loader.cc
+    )
+
+    set(YAZE_APPLE_OBJCXX_SRC
+      app/platform/file_dialog.mm
+      app/platform/app_delegate.mm
+      app/platform/font_loader.mm
+    )
+
+    add_library(yaze_app_objcxx OBJECT ${YAZE_APPLE_OBJCXX_SRC})
+    set_target_properties(yaze_app_objcxx PROPERTIES
+      OBJCXX_STANDARD 20
+      OBJCXX_STANDARD_REQUIRED ON
+    )
+
+    target_include_directories(yaze_app_objcxx PUBLIC
+      ${CMAKE_SOURCE_DIR}/src
+      ${CMAKE_SOURCE_DIR}/src/app
+      ${CMAKE_SOURCE_DIR}/src/lib
+      ${CMAKE_SOURCE_DIR}/src/lib/imgui
+      ${CMAKE_SOURCE_DIR}/incl
+      ${SDL2_INCLUDE_DIR}
+      ${PROJECT_BINARY_DIR}
+    )
+    target_link_libraries(yaze_app_objcxx PUBLIC ${ABSL_TARGETS} yaze_util)
+    target_compile_definitions(yaze_app_objcxx PUBLIC MACOS)
+
+    find_library(COCOA_LIBRARY Cocoa)
+    if(NOT COCOA_LIBRARY)
+        message(FATAL_ERROR "Cocoa not found")
+    endif()
+    set(CMAKE_EXE_LINKER_FLAGS "-framework ServiceManagement -framework Foundation -framework Cocoa")
+endif()
+
+# Create the application core library
+add_library(yaze_app_core_lib STATIC 
+  ${YAZE_APP_CORE_SRC}
+  $<$<BOOL:${APPLE}>:$<TARGET_OBJECTS:yaze_app_objcxx>>
+)
+
+target_precompile_headers(yaze_app_core_lib PRIVATE
+  "$<$<COMPILE_LANGUAGE:CXX>:${CMAKE_SOURCE_DIR}/src/yaze_pch.h>"
+)
+
+target_include_directories(yaze_app_core_lib PUBLIC
+  ${CMAKE_SOURCE_DIR}/src
+  ${CMAKE_SOURCE_DIR}/src/app
+  ${CMAKE_SOURCE_DIR}/src/lib
+  ${CMAKE_SOURCE_DIR}/src/lib/imgui
+  ${CMAKE_SOURCE_DIR}/incl
+  ${SDL2_INCLUDE_DIR}
+  ${PROJECT_BINARY_DIR}
+)
+
+target_link_libraries(yaze_app_core_lib PUBLIC
+  yaze_core_lib    # Foundational core library with project management
+  yaze_util
+  yaze_gfx
+  yaze_zelda3
+  yaze_common
+  ImGui
+  ${ABSL_TARGETS}
+  ${SDL_TARGETS}
+  ${CMAKE_DL_LIBS}
+)
+
+# Link nativefiledialog-extended for Windows/Linux file dialogs
+if(WIN32 OR (UNIX AND NOT APPLE))
+  add_subdirectory(${CMAKE_SOURCE_DIR}/src/lib/nativefiledialog-extended ${CMAKE_BINARY_DIR}/nfd EXCLUDE_FROM_ALL)
+  target_link_libraries(yaze_app_core_lib PUBLIC nfd)
+  target_include_directories(yaze_app_core_lib PUBLIC ${CMAKE_SOURCE_DIR}/src/lib/nativefiledialog-extended/src/include)
+endif()
+
+# gRPC Services (Optional)
+if(YAZE_WITH_GRPC)
+  target_include_directories(yaze_app_core_lib PRIVATE
+    ${CMAKE_SOURCE_DIR}/third_party/json/include)
+  target_compile_definitions(yaze_app_core_lib PRIVATE YAZE_WITH_JSON)
+
+  # Add proto definitions for ROM service and canvas automation
+  # NOTE: Test harness proto is in test.cmake with yaze_test_support
+  target_add_protobuf(yaze_app_core_lib
+    ${PROJECT_SOURCE_DIR}/src/protos/rom_service.proto)
+  target_add_protobuf(yaze_app_core_lib
+    ${PROJECT_SOURCE_DIR}/src/protos/canvas_automation.proto)
+
+  # Add unified gRPC server (non-test services only)
+  target_sources(yaze_app_core_lib PRIVATE
+    ${CMAKE_SOURCE_DIR}/src/app/service/unified_grpc_server.cc
+    ${CMAKE_SOURCE_DIR}/src/app/service/unified_grpc_server.h
+  )
+
+  target_link_libraries(yaze_app_core_lib PUBLIC
+    grpc++
+    grpc++_reflection
+  )
+  if(YAZE_PROTOBUF_TARGETS)
+    target_link_libraries(yaze_app_core_lib PUBLIC ${YAZE_PROTOBUF_TARGETS})
+    if(MSVC AND YAZE_PROTOBUF_WHOLEARCHIVE_TARGETS)
+      foreach(_yaze_proto_target IN LISTS YAZE_PROTOBUF_WHOLEARCHIVE_TARGETS)
+        target_link_options(yaze_app_core_lib PUBLIC /WHOLEARCHIVE:$<TARGET_FILE:${_yaze_proto_target}>)
+      endforeach()
+    endif()
+  endif()
+  
+  message(STATUS "  - gRPC ROM service + canvas automation enabled")
+endif()
+
+# Platform-specific libraries
+if(APPLE)
+  target_link_libraries(yaze_app_core_lib PUBLIC ${COCOA_LIBRARY})
+endif()
+
+set_target_properties(yaze_app_core_lib PROPERTIES
+  POSITION_INDEPENDENT_CODE ON
+  ARCHIVE_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}/lib"
+  LIBRARY_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}/lib"
+)
+
+# Platform-specific compile definitions
+if(UNIX AND NOT APPLE)
+  target_compile_definitions(yaze_app_core_lib PRIVATE linux stricmp=strcasecmp)
+elseif(APPLE)
+  target_compile_definitions(yaze_app_core_lib PRIVATE MACOS)
+elseif(WIN32)
+  target_compile_definitions(yaze_app_core_lib PRIVATE WINDOWS)
+endif()
+
+message(STATUS "✓ yaze_app_core_lib library configured (application layer)")
+
+# ==============================================================================
+# Yaze Application Executable
+# ==============================================================================
 
 if (APPLE)
   add_executable(yaze MACOSX_BUNDLE app/main.cc ${YAZE_RESOURCE_FILES})
diff --git a/src/app/core/core_library.cmake b/src/app/core/core_library.cmake
deleted file mode 100644
index 47209e48..00000000
--- a/src/app/core/core_library.cmake
+++ /dev/null
@@ -1,175 +0,0 @@
-# ==============================================================================
-# Application Core Library (Platform, Controller, Services)
-# ==============================================================================
-# This file defines the application-level core components that were moved
-# from the monolithic app/core structure. This is distinct from the foundational
-# yaze_core_lib in src/core/ which handles project management and asar.
-#
-# Components:
-# - ROM management (app/rom.cc)
-# - Application controller (app/controller.cc)
-# - Window/platform management (app/platform/)
-# - gRPC services for AI automation (app/service/)
-# - Test harness (app/test/)
-#
-# Dependencies: yaze_core_lib (foundational), yaze_util, yaze_gfx, SDL2, ImGui
-# ==============================================================================
-
-set(
-  YAZE_APP_CORE_SRC
-  app/controller.cc
-  app/platform/window.cc
-)
-
-# Platform-specific sources
-if (WIN32 OR MINGW OR (UNIX AND NOT APPLE))
-  list(APPEND YAZE_APP_CORE_SRC
-    app/platform/font_loader.cc
-    app/platform/asset_loader.cc
-    app/platform/file_dialog_nfd.cc  # NFD file dialog for Windows/Linux
-  )
-endif()
-
-if(APPLE)
-    list(APPEND YAZE_APP_CORE_SRC
-      app/platform/font_loader.cc
-      app/platform/asset_loader.cc
-    )
-
-    set(YAZE_APPLE_OBJCXX_SRC
-      app/platform/file_dialog.mm
-      app/platform/app_delegate.mm
-      app/platform/font_loader.mm
-    )
-
-    add_library(yaze_app_objcxx OBJECT ${YAZE_APPLE_OBJCXX_SRC})
-    set_target_properties(yaze_app_objcxx PROPERTIES
-      OBJCXX_STANDARD 20
-      OBJCXX_STANDARD_REQUIRED ON
-    )
-
-    target_include_directories(yaze_app_objcxx PUBLIC
-      ${CMAKE_SOURCE_DIR}/src
-      ${CMAKE_SOURCE_DIR}/src/app
-      ${CMAKE_SOURCE_DIR}/src/lib
-      ${CMAKE_SOURCE_DIR}/src/lib/imgui
-      ${CMAKE_SOURCE_DIR}/incl
-      ${SDL2_INCLUDE_DIR}
-      ${PROJECT_BINARY_DIR}
-    )
-    target_link_libraries(yaze_app_objcxx PUBLIC ${ABSL_TARGETS} yaze_util)
-    target_compile_definitions(yaze_app_objcxx PUBLIC MACOS)
-
-    find_library(COCOA_LIBRARY Cocoa)
-    if(NOT COCOA_LIBRARY)
-        message(FATAL_ERROR "Cocoa not found")
-    endif()
-    set(CMAKE_EXE_LINKER_FLAGS "-framework ServiceManagement -framework Foundation -framework Cocoa")
-endif()
-
-# ==============================================================================
-# Application Core Library
-# ==============================================================================
-# Renamed from old yaze_core_lib to yaze_app_core_lib to distinguish from
-# the foundational yaze_core_lib in src/core/
-# ==============================================================================
-
-add_library(yaze_app_core_lib STATIC 
-  app/rom.cc
-  ${YAZE_APP_CORE_SRC}
-  $<$<BOOL:${APPLE}>:$<TARGET_OBJECTS:yaze_app_objcxx>>
-)
-
-target_precompile_headers(yaze_app_core_lib PRIVATE
-  "$<$<COMPILE_LANGUAGE:CXX>:${CMAKE_SOURCE_DIR}/src/yaze_pch.h>"
-)
-
-target_include_directories(yaze_app_core_lib PUBLIC
-  ${CMAKE_SOURCE_DIR}/src
-  ${CMAKE_SOURCE_DIR}/src/app
-  ${CMAKE_SOURCE_DIR}/src/lib
-  ${CMAKE_SOURCE_DIR}/src/lib/imgui
-  ${CMAKE_SOURCE_DIR}/incl
-  ${SDL2_INCLUDE_DIR}
-  ${PROJECT_BINARY_DIR}
-)
-
-target_link_libraries(yaze_app_core_lib PUBLIC
-  yaze_core_lib    # NEW foundational core library with project management
-  yaze_util
-  yaze_gfx
-  yaze_zelda3
-  yaze_common
-  ImGui
-  ${ABSL_TARGETS}
-  ${SDL_TARGETS}
-  ${CMAKE_DL_LIBS}
-)
-
-# Link nativefiledialog-extended for Windows/Linux file dialogs
-if(WIN32 OR (UNIX AND NOT APPLE))
-  add_subdirectory(${CMAKE_SOURCE_DIR}/src/lib/nativefiledialog-extended ${CMAKE_BINARY_DIR}/nfd EXCLUDE_FROM_ALL)
-  target_link_libraries(yaze_app_core_lib PUBLIC nfd)
-  target_include_directories(yaze_app_core_lib PUBLIC ${CMAKE_SOURCE_DIR}/src/lib/nativefiledialog-extended/src/include)
-endif()
-
-# ==============================================================================
-# gRPC Services and Test Harness (Optional)
-# ==============================================================================
-
-if(YAZE_WITH_GRPC)
-  target_include_directories(yaze_app_core_lib PRIVATE
-    ${CMAKE_SOURCE_DIR}/third_party/json/include)
-  target_compile_definitions(yaze_app_core_lib PRIVATE YAZE_WITH_JSON)
-
-  # Add proto definitions for ROM service and canvas automation
-  # NOTE: Test harness proto moved to test.cmake with yaze_test_support
-  target_add_protobuf(yaze_app_core_lib
-    ${PROJECT_SOURCE_DIR}/src/protos/rom_service.proto)
-  target_add_protobuf(yaze_app_core_lib
-    ${PROJECT_SOURCE_DIR}/src/protos/canvas_automation.proto)
-
-  # Add unified gRPC server (non-test services only)
-  target_sources(yaze_app_core_lib PRIVATE
-    ${CMAKE_SOURCE_DIR}/src/app/service/unified_grpc_server.cc
-    ${CMAKE_SOURCE_DIR}/src/app/service/unified_grpc_server.h
-  )
-
-  target_link_libraries(yaze_app_core_lib PUBLIC
-    grpc++
-    grpc++_reflection
-  )
-  if(YAZE_PROTOBUF_TARGETS)
-    target_link_libraries(yaze_app_core_lib PUBLIC ${YAZE_PROTOBUF_TARGETS})
-    if(MSVC AND YAZE_PROTOBUF_WHOLEARCHIVE_TARGETS)
-      foreach(_yaze_proto_target IN LISTS YAZE_PROTOBUF_WHOLEARCHIVE_TARGETS)
-        target_link_options(yaze_app_core_lib PUBLIC /WHOLEARCHIVE:$<TARGET_FILE:${_yaze_proto_target}>)
-      endforeach()
-    endif()
-  endif()
-  
-  message(STATUS "  - gRPC ROM service + canvas automation enabled")
-  message(STATUS "  - gRPC test harness moved to yaze_test_support (avoid circular deps)")
-endif()
-
-# Platform-specific libraries
-if(APPLE)
-  target_link_libraries(yaze_app_core_lib PUBLIC ${COCOA_LIBRARY})
-endif()
-
-set_target_properties(yaze_app_core_lib PROPERTIES
-  POSITION_INDEPENDENT_CODE ON
-  ARCHIVE_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}/lib"
-  LIBRARY_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}/lib"
-)
-
-# Platform-specific compile definitions
-if(UNIX AND NOT APPLE)
-  target_compile_definitions(yaze_app_core_lib PRIVATE linux stricmp=strcasecmp)
-elseif(APPLE)
-  target_compile_definitions(yaze_app_core_lib PRIVATE MACOS)
-elseif(WIN32)
-  target_compile_definitions(yaze_app_core_lib PRIVATE WINDOWS)
-endif()
-
-message(STATUS "✓ yaze_app_core_lib library configured (application layer)")