Memory model, capability scoping, and the right way to think about node-js sandboxing in multi-tenant systems.
"Isolate" is a word people use to mean very different things. In V8, an isolate is a self-contained JavaScript engine with its own heap and microtask queue.
Two isolates cannot read each other's heap. That alone makes them a useful primitive for multi-tenant nodejs workloads.
What an isolate can do is determined by the host. The Adensabais runtime hands each node-js isolate a capability set — fs, network, env — scoped to the workload manifest.
They do not give you side-channel resistance. For workloads with adversarial tenants, pair isolates with process-level boundaries.