local appVango

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Interactive Labs

Flip the inputs and watch the platform decision change. The point is to build operational reflexes.

Horizontal Scale Readiness

Decide whether multiple allocations are allowed.

Sticky live-session routingDurable session storeBroadcast backendApp uses global live stateCross-allocation resume promisedUnsafe replay routes existIdempotency store bound

Decision

Blocked

Same-region horizontal scale would violate one or more Vango runtime contracts.

Cross-allocation resume requires a durable Vango session store binding.

Global live state fanout requires a broadcast backend such as NATS or Redis pub/sub.

Unsafe replay routes require an idempotency posture before edge wake/retry can be trusted.

Live sessions can stay pinned to their original allocation.

Deploy Impact Gate

Compose Vango state, database impact, sessions, and generated artifacts.

Persisted state change

Database migration impact

Active sessions

Generated artifacts freshRequired approval recorded

Decision

warm

Promotion can proceed under warm deploy policy.

Wake Request Classifier

Classify sleeping/waking traffic before backend selection.

Lifecycle state

Request class

A hot allocation existsExplicit idempotency key

Decision

wake_and_hold 200 or 503

Safe idempotent page requests may wait within the configured wake budget.

NATS/JetStream Route Event

Converge edge workers from snapshots plus durable events.

Verified snapshot loadedJetStream replay available

Last applied route epoch

Incoming route epoch

Replay gap detected

Decision

apply event

The event advances the route epoch from a verified baseline with replay continuity.

Drain, Resume, Or Fresh Session

Choose the honest session continuity mode during replacement or failure.

Active WebSocket existsDurable session storeState schema compatibleOld allocation healthyDrain deadline expired

Decision

drain in place

The existing live session remains attached to the old allocation while new sessions route elsewhere.

mark old allocation no-new-sessions

route new sessions to replacement

wait for close or drain deadline

Multi-Region Enablement

Route eligibility is gated by data, runtime, secrets, artifacts, and residency.

Artifact replicatedRuntime services readyDatabase/data readyResidency policy allowsRegion secrets readyPromises live-session move

Decision

Blocked

Do not route traffic to the new region until each correctness-bearing dependency is ready.

Required session, broadcast, cache, queue, or idempotency bindings are not region-ready.

Database topology, migrations, bootstrap data, or credentials are not ready.

OS Upgrade Host Drain

Treat host upgrades as scheduler-aware drain and replacement operations.

Quorum-capable hosts

Active allocations on host

Runner headroom availableSessions can drain

Decision

Safe

Maintenance is safe under the selected quorum, headroom, and drain posture.

cordon host so no new allocations land there

drain app allocations with no-new-sessions policy

wait for readiness on replacement allocations where needed

preserve route ownership while allocation selection changes

rebuild or upgrade host through bootstrap automation

run runner, edge, scheduler, and observability checks

uncordon host after health and drift checks pass