Recap In the previous chapters, we explored: Scheduler internals Memory and graph management Priority and layered scheduling Time-slicing and cooperative scheduling All of these mechanisms are essential for making a reactivity system work correctly internally. But internal correctness alone is not enough. For developers, the more important question is: How do we observe, debug, and understand the system? That is where DevTools and diagnostics become critical. Inspecting Nodes Why do we need inspect() ? One of the most common debugging needs during development is: “What is the current value of this signal or computed?” If the only solution is console.log , debugging quickly becomes inconvenient and intrusive. A proper inspection layer gives developers visibility without polluting application logic.…