async function handle(event) if (event.type === "TRANSACTION") return await processTx(event.data);

// State persistence state consecutive_failures = 0

for (const target of targets) const result = await checkEndpoint(target); if (!result.healthy) console.error(`[FAIL] $target - $result.error`); state.consecutive_failures++; if (state.consecutive_failures >= 3) console.log("Initiating recovery procedure..."); await executeRecovery(target); state.consecutive_failures = 0; else console.log(`[PASS] $target - $result.latencyms`); state.consecutive_failures = Math.max(0, state.consecutive_failures - 1);

| Feature | Fly V2 | Fly V3 | | :--- | :--- | :--- | | Syntax | Callback-based ( callback(err, res) ) | Async/Await | | State | Volatile (lost on restart) | Persistent (disk-backed) | | Concurrency | Manual Promise.all | Built-in Fly.parallelMap | | Error Handling | .catch() blocks | Try/Catch with automatic retries |