What is an Isolate in Dart?
Why Interviewers Ask This
Mid-level Flutter roles require deep understanding of this topic. Interviewers ask this to separate candidates who truly understand the mechanics from those who only know surface-level concepts.
Answer
Dart is single-threaded, but you can achieve true parallelism using Isolates — independent workers that have their own memory heap and Dart event loop. Isolates do not share memory; they communicate by passing messages through ports. This design eliminates race conditions. Use isolates for CPU-intensive work like parsing large JSON, image processing, or complex computations that would otherwise freeze the UI. The simpler compute() function is a shortcut for spawning a one-off isolate and returning its result.
Pro Tip
This topic has Flutter-specific nuances that differ from general programming. Highlighting those nuances in your answer shows expertise rather than generic knowledge.