Application settings have sensible defaults for new users

New users who land in a broken default state — blank required fields, null configuration, a settings page they must complete before anything works — don't file bug reports. They churn silently. ISO 25010 functional suitability covers exactly this failure: the software doesn't do what a new user reasonably expects it to do on first run. Missing defaults also create data integrity hazards: if a default timezone is never set, date math silently breaks on the first query that needs it.

Define defaults at the database schema level so they're persisted on account creation, not just applied as runtime fallbacks. In prisma/schema.prisma:

model UserSettings {
  id           String  @id @default(cuid())
  userId       String  @unique
  emailNotifs  Boolean @default(true)
  theme        String  @default("system")
  timezone     String  @default("UTC")
  language     String  @default("en")
}

In your account creation handler, call prisma.userSettings.create({ data: { userId } }) immediately after inserting the user — the schema defaults fill the rest. Never rely on application-layer fallbacks to cover missing rows.