frontend-error-handling

Avoid deep try-catch nesting in sequential async flows by treating errors as values with the AsyncResult and tryCatchAsync patterns, which preserve linear control flow for dependent mutations.

Manage independent parallel fetch calls with Promise.allSettled to prevent one failed request from rejecting the entire batch, preserving individual error states for each parallel task.

Branch user-friendly messages by applying ky HTTPError type guards to catch specific 400, 409, and 422 status codes, enabling targeted domain-specific feedback for API request failures.

Isolate rendering-time exceptions by wrapping vulnerable UI sections with ErrorBoundary components to catch throws and display fallback interfaces without crashing the entire application.

Use simple try-catch for single API requests where immediate failure is acceptable, and reserve Promise.allSettled for independent parallel tasks where surviving requests must continue processing.

Standardize order, payment, and delivery flows by combining AsyncResult for sequential mutations, ky HTTPError branching for API failures, and ErrorBoundary for UI section fallbacks.