diff --git a/CMakeLists.txt b/CMakeLists.txt
index a01e73d3..a2f25eb6 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -2,7 +2,7 @@
 # Copyright Benoit Blanchon 2014-2021
 # MIT License
 
-cmake_minimum_required(VERSION 3.3)
+cmake_minimum_required(VERSION 3.15)
 
 if(ESP_PLATFORM)
    # Build ArduinoJson as an ESP-IDF component
diff --git a/appveyor.yml b/appveyor.yml
index edabdf00..38ec08a3 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -9,8 +9,7 @@ environment:
     CMAKE_GENERATOR: Visual Studio 15 2017
   - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2015
     CMAKE_GENERATOR: Visual Studio 14 2015
-  - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2013
-    CMAKE_GENERATOR: Visual Studio 12 2013
+  - CMAKE_GENERATOR: Visual Studio 12 2013
   - CMAKE_GENERATOR: Visual Studio 11 2012
   - CMAKE_GENERATOR: Visual Studio 10 2010
   - CMAKE_GENERATOR: MinGW Makefiles