Fix · Speed

The JavaScript is too big (slow to start)

What you may see

The speed tool says reduce unused JavaScript
A small page ships a huge script

Most likely cause

A big library imported in full, or code for pages the visitor never opens, is sent to everyone.

Check first (about two minutes)

Run the build's size report (or a bundle analyser, with my permission to add it).

The fix prompt

What you type here never leaves your browser. The search runs on this page, and nothing is sent to a server or to an AI.

The exact error or what you see

What you did before it happened

Kept only in this browser, on this device. Keys and passwords are removed before anything is saved.

Prompt language

You are a senior web performance engineer who explains speed problems to people who are not developers. I am not a developer, so explain every step in plain words and tell me exactly which button, menu or command you mean. If you are not sure about something, say so; do not guess.

THE PROBLEM
The JavaScript is too big (slow to start)

THE EXACT ERROR OR WHAT I SEE
[paste the exact error here]

WHAT I DID BEFORE IT HAPPENED
[write in a few words what you did before it happened]

MOST LIKELY CAUSE
A big library imported in full, or code for pages the visitor never opens, is sent to everyone.

DO THESE STEPS, IN THIS ORDER
1. Find the biggest packages in the page's script and what uses them.
2. Replace heavy libraries with light ones or native features, import only what is used, and load big pieces only when needed (dynamic import).
3. Re-measure the size of the first page load.
Stop and tell me if what you see does not match a step. Do not skip ahead.

CHECK THAT IT WORKED
- The first page script is clearly smaller and everything still works.
Tell me exactly what I should see on the screen when it works.

DO NOT CHANGE
- Do not remove features without asking.
- Anything I did not ask about: the design, the text, other pages, other settings or the data.
- Do not delete files, data or branches, do not reset or force-push, and do not rewrite history, unless you first show me exactly what would be lost and I say yes.
- Do not paste, print or ask me to paste a password or secret key into this chat. If one is needed, tell me which settings page of the right service to store it in.

WHEN YOU FINISH
Explain in simple words what you changed (file by file or setting by setting), why you changed it, and how I can undo it.

Paste it into Claude, ChatGPT, Gemini or Cursor, then follow what it says.

After you tried it, did it work?

Steps

Find the biggest packages in the page's script and what uses them.
Replace heavy libraries with light ones or native features, import only what is used, and load big pieces only when needed (dynamic import).
Re-measure the size of the first page load.

Do not do this

Do not add a bundle tool without telling me.
Do not remove features without asking.

Try another entry