◆ JavaScript

Optimize JavaScript for high performance

This is real work, not a feature someone invented — it comes from real job ads and real questions people asked. Below are four ready AI prompts: get it done, make it easy for the next person to say yes to, work out the right move when you are stuck, and stop it coming back.

4prompts

The same task, four prompts

today's deadline · the next reviewer · the stuck moment · the pattern
AExecute — do the immediate taskReview this JavaScript function and suggest any obvious changes to make it run faster,…+
Review this JavaScript function and suggest any obvious changes to make it run faster, especially if it's called frequently.
when the reply comes backPush once: ask it to sharpen the weakest part, and to say what it assumed. Helpful?
BImprove — make it easier to acceptBefore I deploy this new dashboard feature, analyze the JavaScript code for performance…+
Before I deploy this new dashboard feature, analyze the JavaScript code for performance bottlenecks. Suggest specific optimizations, especially for data processing and DOM manipulation, so the dashboard loads quickly and feels responsive to users on older devices.
when the reply comes backPush once: ask it to sharpen the weakest part, and to say what it assumed. Helpful?
CDecide — diagnose the stuck momentThe new product catalog page is taking 5-7 seconds to become interactive, which is unacceptable…+
The new product catalog page is slow to load, and I'm not sure where the bottleneck is.
The new product catalog page is taking 5-7 seconds to become interactive, which is unacceptable for our users. I've profiled it, but the waterfall chart shows many small scripts and image loads contributing, and I can't pinpoint one major bottleneck in the page's interactivity. The marketing team is furious, and we need this fixed by Monday. I'm afraid of making changes that break existing functionality. What's the most effective way to identify the biggest performance culprits for page interactivity and what's the safest first step to optimize it?
when the reply comes backPush once: ask it to sharpen the weakest part, and to say what it assumed. Helpful?
DBecome — change the patternMy web applications consistently get flagged for poor performance after they go live, leading…+
My JavaScript applications frequently get flagged for poor performance after launch.
My web applications consistently get flagged for poor performance after they go live, leading to user complaints and emergency fixes. I often focus on functionality first and optimize later, but it always bites me. What habit should I change in my development workflow to proactively build performant web applications from the start, instead of scrambling to optimize under pressure?
when the reply comes backPush once: ask it to sharpen the weakest part, and to say what it assumed. Helpful?

Questions people actually ask

honest answers, no sign-up

Every task here was seen in the real world. Someone doing the job named it, a real job ad asked for it, or a lot of people asked about it online.

If nothing real showed a task, it is not on the page. That is the whole rule.

They are the same job approached four ways, because what you need depends on where you are.

Get it done today. Make it easy for the next person to say yes to. Work out the right move when you are stuck. Learn the pattern so the job stops coming back.

For most of these jobs it can carry the heavy thinking - draft it, sort it, check it, rehearse it with you.

It cannot sit in your chair, take the blame when a number is wrong, or notice what nobody wrote down. Let it do the first 80%. Keep the last 20% that is truly yours.

No. Copy any prompt and paste it into the AI you already use. No account, no score, no wall in the way.

Any of them. The prompts describe the work rather than naming a product, so they are not tied to one assistant.

That is also why they keep working when you switch.

Change it freely. Every prompt is a starting line, not a rule.

Put in your real numbers, your real names and your real deadline. The more you make it yours, the better the answer comes back.

The tasks come from real job ads, published job data and the questions people ask in public forums.

The steps come from JavaScript's own documentation, with practitioner sources for the traps the manual does not mention.

Push once. Ask it to sharpen the weakest part and to say what it assumed.

Most wrong answers come from a missing detail rather than a bad prompt - tell it the thing it could not know.