docs(frontend-python): add compiler verbose and debug modes to how to…

… debug

docs/howto/debug.md

@@ -2,6 +2,17 @@
 
 In this section, you will learn how to debug the compilation process easily and find help in the case that you cannot resolve your issue.
 
+## Compiler debug and verbose modes
+
+There are two [configuration](../howto/configure.md) options that you can use to understand what's happening under the hood during compilation process.
+
+- **compiler_verbose_mode** will print the passes applied by the compiler and let you see the transformations done by the compiler. Also, in case of crashes, it could narrow down the crash location. 
+- **compiler_debug_mode** is a lot more detailed version of the verbose mode. Even better for crashes.
+
+{% hint style="warning" %}
+These flags might not work as expected in Jupyter notebooks as they output to stderr directly from C++.
+{% endhint %}
+
 ## Debug artifacts
 
 **Concrete** has an artifact system to simplify the process of debugging issues.