update ReadMe:Building

README.md

@@ -17,4 +17,12 @@ It is not shown here, but when using a *model* it doesn't have to be a `QObject`
 
 # Building
 
-Should work out of the box with Qt Creator, VSCode and the CMake and C++ plugins installed.  
+Should work out of the box with Qt Creator, VSCode and the CMake and C++ plugins installed.  
\ No newline at end of file
+
+    [cmake] CMake Error: CMake was unable to find a build program corresponding to "Unix Makefiles".  CMAKE_MAKE_PROGRAM is not set.  You probably need to select a different build tool.
+
+    #Manjaro:
+    sudo pacman -S base-devel
+
+    #Ubuntu:
+    sudo apt install build-essential
\ No newline at end of file