diff --git a/cmake/AnyAvrGcc.cmake b/cmake/AnyAvrGcc.cmake
index e050888..65f1871 100644
--- a/cmake/AnyAvrGcc.cmake
+++ b/cmake/AnyAvrGcc.cmake
@@ -2,6 +2,10 @@ get_filename_component(PROJECT_CMAKE_DIR "${CMAKE_CURRENT_LIST_FILE}" DIRECTORY)
 include("${PROJECT_CMAKE_DIR}/Utilities.cmake")
 set(CMAKE_SYSTEM_NAME Generic)
 set(CMAKE_SYSTEM_PROCESSOR avr)
+set(gcc_version 7.3.0)
+# set(CMAKE_CROSSCOMPILING 1)
+set(AVR_TOOLCHAIN_DIR "${PROJECT_CMAKE_DIR}/../.dependencies/gcc-avr-${gcc_version}/")
+message("ToolChain dir is ${AVR_TOOLCHAIN_DIR}")
 
 #
 # Utilities
diff --git a/src/main.cpp b/src/main.cpp
index b37af1b..3039277 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -166,3 +166,9 @@ int main() {
     }
     return 0;
 }
+
+// avoid avr-gcc 5.4 link time code generation bug
+extern "C" void __cxa_pure_virtual() {
+    while (1)
+        ;
+}
diff --git a/utils/bootstrap.py b/utils/bootstrap.py
index e01994a..5cbe7cc 100755
--- a/utils/bootstrap.py
+++ b/utils/bootstrap.py
@@ -29,30 +29,28 @@ dependencies_dir = project_root_dir / '.dependencies'
 # yapf: disable
 dependencies = {
     'ninja': {
-        'version': '1.9.0',
+        'version': '1.10.2',
         'url': {
-            'Linux': 'https://github.com/ninja-build/ninja/releases/download/v1.9.0/ninja-linux.zip',
-            'Windows': 'https://github.com/ninja-build/ninja/releases/download/v1.9.0/ninja-win.zip',
-            'Darwin': 'https://github.com/ninja-build/ninja/releases/download/v1.9.0/ninja-mac.zip',
+            'Linux': 'https://github.com/ninja-build/ninja/releases/download/v1.10.2/ninja-linux.zip',
+            'Windows': 'https://github.com/ninja-build/ninja/releases/download/v1.10.2/ninja-win.zip',
+            'Darwin': 'https://github.com/ninja-build/ninja/releases/download/v1.10.2/ninja-mac.zip',
         },
     },
     'cmake': {
-        'version': '3.15.5',
+        'version': '3.21.3',
         'url': {
-            'Linux': 'https://github.com/Kitware/CMake/releases/download/v3.15.5/cmake-3.15.5-Linux-x86_64.tar.gz',
-            'Windows': 'https://github.com/Kitware/CMake/releases/download/v3.15.5/cmake-3.15.5-win64-x64.zip',
-            'Darwin': 'https://github.com/Kitware/CMake/releases/download/v3.15.5/cmake-3.15.5-Darwin-x86_64.tar.gz',
+            'Linux': 'https://github.com/Kitware/CMake/releases/download/v3.21.3/cmake-3.21.3-linux-x86_64.tar.gz',
+            'Windows': 'https://github.com/Kitware/CMake/releases/download/v3.21.3/cmake-3.21.3-windows-x86_64.zip',
+            'Darwin': 'https://github.com/Kitware/CMake/releases/download/v3.21.3/cmake-3.21.3-macos-universal.tar.gz',
         },
     },
     'gcc-avr': {
-        # dummy placeholder (currently downloading cmake just for the sake of a valid url/zip archive)
-        # ... we truly need the binaries! :)
-        'version': '0.0.0',
+        'version': '7.3.0',
         'url': {
-            'Linux': 'https://github.com/Kitware/CMake/releases/download/v3.15.5/cmake-3.15.5-Linux-x86_64.tar.gz',
-            'Windows': 'https://github.com/Kitware/CMake/releases/download/v3.15.5/cmake-3.15.5-win64-x64.zip',
-            'Darwin': 'https://github.com/Kitware/CMake/releases/download/v3.15.5/cmake-3.15.5-Darwin-x86_64.tar.gz',
-        }
+            'Linux': 'https://ww1.microchip.com/downloads/aemDocuments/documents/DEV/ProductDocuments/SoftwareTools/avr8-gnu-toolchain-3.7.0.1796-linux.any.x86_64.tar.gz',
+            'Windows': 'https://ww1.microchip.com/downloads/aemDocuments/documents/DEV/ProductDocuments/SoftwareTools/avr8-gnu-toolchain-3.7.0.1796-win32.any.x86_64.zip',
+            'Darwin': 'https://ww1.microchip.com/downloads/aemDocuments/documents/DEV/ProductDocuments/SoftwareTools/avr8-gnu-toolchain-osx-3.7.0.518-darwin.any.x86_64.tar.gz',
+        },
     },
     'clang-format': {
         'version': '9.0.0-noext',