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uploy docs

App won't start

Where to look first

Section titled “Where to look first”

Logs tab of the app. uploy captures stdout/stderr from the container, including panics and unhandled exceptions.

Common causes

Section titled “Common causes”

Wrong start command

Section titled “Wrong start command”
  • Symptom: /bin/sh: <command>: not found in runtime logs.
  • Fix: Nixpacks auto-detects a start command. If yours is non-standard, add a start script in package.json or the language equivalent.

Port binding

Section titled “Port binding”
  • Symptom: App starts but health checks fail.
  • Fix: Bind to 0.0.0.0 on the port in the PORT environment variable. uploy injects PORT at runtime.

Missing environment variable

Section titled “Missing environment variable”

Database not reachable

Section titled “Database not reachable”
  • Symptom: App boots, immediately fails to connect to Postgres.
  • Fix: Confirm a managed Postgres is attached, not just created. Attachment injects DATABASE_URL. See Database connection errors.

If none of the above matches

Section titled “If none of the above matches”

Contact support with the app URL and the last runtime log lines.