Should I commit my .env file so the build can read it?

No. Keep .env out of Git and add the variables in Netlify’s or Vercel’s settings instead. Never put a secret such as a Supabase service_role key or a Stripe secret key in a VITE_ variable, because Vite builds those into code anyone can read.

The build passes but the live site is blank. Why?

Usually a VITE_ variable was missing at build time, so the app starts with an undefined URL or key and stops. Open the browser console on the live site, add the missing variable in the host’s settings, and redeploy.

Can I fix it inside Bolt or Lovable instead?

Sometimes. Ask the builder to fix the exact first error from the build log, then run the production build command locally (usually npm run build) before deploying again. If it keeps coming back, the same error is worth fixing by hand.

Can you fix it for me?

If one bug is the whole problem, the App Fix Ticket covers it: a written diagnosis first, then the fix. If the app has more going on, the Launch Check is a written check of the whole app. Each issue found is rated critical, high, medium or low, with where it is and how it was confirmed. No issues worth fixing, no charge. If the Launch Check finds nothing rated medium or higher, Simon refunds the full $450. You keep the report either way.

Bolt or Lovable Build Fails on Netlify or Vercel

Short answer

Scroll up the build log to the first error, not the last line. Most often it’s a missing environment variable: Vite builds VITE_ variables into the code at build time, and Netlify doesn’t read .env files, so they must be set in the host’s settings. Next: a different Node version, a file name whose capital letters don’t match the import, or warnings treated as errors.

The four usual causes, and the fix

01
Environment variables missing at build time
Vite replaces VITE_ variables with their values when it builds, so they have to exist on the build machine. Netlify doesn’t read .env files during builds: add each variable in the site’s settings with the Builds scope. On Vercel, changed variables apply only to new deployments, so redeploy after adding them. Only put public values in VITE_ variables, since they end up in the browser.
02
A different Node version
The build machine uses its default Node version, which may not match yours. On Netlify, set a NODE_VERSION environment variable or add a .nvmrc file. On Vercel, set the Node.js version in the project’s build settings, or engines.node in package.json, which overrides the project setting.
```
// package.json (Vercel)
"engines": { "node": "22.x" }

# .nvmrc (Netlify)
22
```
03
File name case doesn’t match the import
Mac and Windows treat Button.tsx and button.tsx as the same file; Netlify’s build machine doesn’t. An import that works on your laptop fails there, and Netlify warns the error may not say so. Match every import to the file’s exact name. To rename a file’s case, use git mv so Git records the change.
04
Warnings treated as errors, or peer dependency conflicts
Netlify sets CI=true, and some tools then fail the build on warnings. Netlify’s fix is to start the build command with CI='' (CI=false may not work). For "Could not resolve dependency" or "Conflicting peer dependency" errors, Netlify’s fix is an NPM_FLAGS environment variable set to --legacy-peer-deps. Also confirm the publish directory matches your build output folder (dist for a default Vite app).

Checked against the vendor’s docs on October 30, 2026: Vite docs: Env variables and modes; Netlify docs: Environment variables; Netlify docs: Manage build dependencies (Node.js version); Netlify docs: Build troubleshooting tips; Vercel docs: Environment variables; Vercel docs: Node.js versions.

Rather hand it over?

Fixed scope, fixed price, paid upfront. The work happens in writing; no call needed.

Netlify and Vercel build errorThe app works in Bolt or Lovable, but the deploy build fails

The four usual causes, and the fix

Environment variables missing at build time

A different Node version

File name case doesn’t match the import

Warnings treated as errors, or peer dependency conflicts

Rather hand it over?

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