Fix · Node, npm and build

Mixed package managers (npm, yarn, pnpm lock files)

What you may see

The project has more than one lock file
Installs give different versions on different machines

Most likely cause

Two tools install the same project and each writes its own lock file, so people get different packages.

Check first (about two minutes)

List the files in the root with names ending in lock.

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 patient senior engineer who knows Node.js, npm and build tools and explains them 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
Mixed package managers (npm, yarn, pnpm lock files)

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
Two tools install the same project and each writes its own lock file, so people get different packages.

DO THESE STEPS, IN THIS ORDER
1. Find which lock files exist and which one the host uses.
2. Choose ONE manager with me, keep only its lock file, and note it in package.json (packageManager) and the README.
3. Reinstall from that lock file and run the build.
Stop and tell me if what you see does not match a step. Do not skip ahead.

CHECK THAT IT WORKED
- One lock file remains and a clean install gives the same result as the host.
Tell me exactly what I should see on the screen when it works.

DO NOT CHANGE
- Do not delete the lock file you keep.
- 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 which lock files exist and which one the host uses.
Choose ONE manager with me, keep only its lock file, and note it in package.json (packageManager) and the README.
Reinstall from that lock file and run the build.

Do not do this

Do not use two managers on the same project.
Do not delete the lock file you keep.

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