guide: add user journey live debugging document

locale/en/docs/guides/diagnostics/index.md

@@ -16,5 +16,6 @@ root-cause their issues.
 This is the available set of diagnostics guides:
 
 * [Memory](/en/docs/guides/diagnostics/memory)
+* [Live Debugging](/en/docs/guides/diagnostics/live-debugging)
 
 [Diagnostics Working Group]: https://github.com/nodejs/diagnostics

locale/en/docs/guides/diagnostics/live-debugging/index.md

@@ -0,0 +1,31 @@
+---
+title: Live Debugging
+layout: docs.hbs
+---
+
+# Live Debugging
+
+* [Live Debugging](#live-debugging)
+  * [My application doesn’t behave as expected](#my-application-doesnt-behave-as-expected)
+    * [Symptoms](#symptoms)
+    * [Debugging](#debugging)
+
+In this document you can learn about how to live debug a Node.js process.
+
+## My application doesn’t behave as expected
+
+### Symptoms
+
+The user may observe that the application doesn’t provide the expected output
+for certain inputs, for example, an HTTP server returns a JSON response where
+certain fields are empty. Various things can go wrong in the process but in this
+use case, we are mainly focused on the application logic and its correctness.
+
+### Debugging
+
+In this use case, the user would like to understand the code path that our
+application executes for a certain trigger like an incoming HTTP request. They
+may also want to step through the code and control the execution as well as
+inspect what values variables hold in memory.
+
+* [Using Inspector](/en/docs/guides/diagnostics/live-debugging/using-inspector)

locale/en/docs/guides/diagnostics/live-debugging/using-inspector.md

@@ -0,0 +1,17 @@
+---
+title: Using Inspector
+layout: docs.hbs
+---
+
+# Using Inspector
+
+In a local environment, we usually speak about live debugging where we attach a
+debugger to our application and we add breakpoints to suspend the program
+execution. Then we step through the code paths and inspect our heap over the
+different steps. Using the live debugger in production is usually not an option
+as we have limited access to the machine and we cannot interrupt the execution
+of the application as it handles a business-critical workload.
+
+## How To
+
+https://nodejs.org/en/docs/guides/debugging-getting-started/