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Public debug memory

Vercel build failed because env variable is missing

Added May 7, 2026 · fingerprint 10a302a76b69fb0c

VercelNext.jsSupabase
Error message
Error: Missing NEXT_PUBLIC_SUPABASE_URL
Validated candidate
Candidate fix

Add the missing environment variable in Vercel project settings for the correct environment and redeploy.

Snippets are manually submitted minimal examples. Verytis does not collect full files or repositories automatically.

Broken code

const supabase = createClient(
  process.env.NEXT_PUBLIC_SUPABASE_URL!,
  process.env.NEXT_PUBLIC_SUPABASE_ANON_KEY!
)

Fixed code

# Vercel project environment variables
NEXT_PUBLIC_SUPABASE_URL=https://example-project.supabase.co
NEXT_PUBLIC_SUPABASE_ANON_KEY=public-anon-key

Why this fixed it

The build read a required public Supabase variable that only existed locally. Adding the public environment variables to the Vercel project let the deployment build with the same configuration.

Steps

  1. 1Open Vercel Project Settings > Environment Variables.
  2. 2Add `NEXT_PUBLIC_SUPABASE_URL` to Production, Preview, and Development as needed.
  3. 3Confirm related variables such as `NEXT_PUBLIC_SUPABASE_ANON_KEY` are also set.
  4. 4Redeploy the failed build instead of only restarting the local dev server.
Validation command
npm run build
Proof-of-fix validations are ranked above unverified suggestions.
Known failures
  • The variable exists locally in `.env.local` but not in Vercel.
  • The variable was added only to Preview while the failing deployment is Production.