async/await and the sequential trap in JavaScript

async/await didn't make your code faster. It just made the slowness harder to see. ───────────────────────── Most devs write this and ship it with confidence: const user = await getUser(id) const posts = await getPosts(id) const comments = await getComments(id) Clean. Readable. And quietly costing you 3x the wait time. ───────────────────────── Here's what's actually happening under the hood 👇 async/await is syntax sugar over Promises. Your linear-looking code compiles into a Promise chain. await doesn't block the thread — it pauses that function and resumes it later. Which means: you can run things in parallel. You're just choosing not to. ───────────────────────── The sequential trap When you await three independent requests in a row, you're making them wait for each other — for no reason. Total time = request1 + request2 + request3 On a slow network, that gap is seconds, not milliseconds. ───────────────────────── The fix: Promise.all const [user, posts, comments] = await Promise.all([ getUser(id), getPosts(id), getComments(id) ]) Total time = slowest request only. ───────────────────────── When one failure shouldn't kill the rest: Promise.allSettled Promise.all fails fast — one rejection kills everything. Promise.allSettled lets every Promise finish and returns each result individually. Use it when partial failure is acceptable. ───────────────────────── The error handling gap nobody talks about A floating Promise that rejects has nowhere to go. No catch. No log. Silent failure in production. Rule: every Promise either gets awaited inside a try/catch, or gets a .catch() attached. No exceptions. ───────────────────────── One question that saves you every time: Before writing a second await — ask yourself: Does this actually need to wait for the previous one? If the answer is no, run them together. ───────────────────────── This post took me 5 seconds to write and 2 years of production bugs to learn. If it saves you the same bugs — repost it for your team ♻️ #JavaScript #WebPerformance #FrontendDevelopment #WebDev #Programming

I have faced the same issue and sloved it using primrose

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