Fix · Node, npm and build

process.env.X is undefined (my .env value is not read)

What you may see

A value from my .env file is undefined in the app
It is undefined only in the browser

Most likely cause

The file name or variable name is not what the tool reads, the dev server was not restarted, or browser code needs the public prefix.

Check first (about two minutes)

Is the file in the project root (next to package.json) and named exactly as the tool expects?
Did you stop and start the dev server after editing 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 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
process.env.X is undefined (my .env value is not read)

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
The file name or variable name is not what the tool reads, the dev server was not restarted, or browser code needs the public prefix.

DO THESE STEPS, IN THIS ORDER
1. Show the file NAMES (not contents) in the root, and the variable names the code reads.
2. Explain the prefix rule of this framework for browser code and for server code, and fix the names.
3. Tell me to restart the dev server; check that .env is listed in .gitignore.
Stop and tell me if what you see does not match a step. Do not skip ahead.

CHECK THAT IT WORKED
- The value is read where needed (test with a harmless value like a site name, not a key).
Tell me exactly what I should see on the screen when it works.

DO NOT CHANGE
- Do not print real secret values.
- Do not give a secret a public prefix.
- 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

Show the file NAMES (not contents) in the root, and the variable names the code reads.
Explain the prefix rule of this framework for browser code and for server code, and fix the names.
Tell me to restart the dev server; check that .env is listed in .gitignore.

Do not do this

Do not commit .env.
Do not print real secret values.
Do not give a secret a public prefix.

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