v0.31.0

Minor Changes

• 69bf59e: Breaking: createTaggedError now requires .withMessage(fn) as a mandatory terminal builder step before factories are available.

  What Changed

  • .withMessage(fn) is now required: Factories (XxxError, XxxErr) are only returned after calling .withMessage(). Previously you could destructure factories after just .withContext() or .withCause().
  • Message is auto-computed: The message field is no longer a required input at the factory call site — it is derived from the template function passed to .withMessage(). You can still pass message: as an optional override.
  • Context type tightened: context constraint changed from Record<string, unknown> to JsonObject (values must be JSON-serializable).
  • Strict builder/factory separation: ErrorBuilder only has chain methods (.withContext(), .withCause(), .withMessage()). FinalFactories only has factory functions — no more mixing.

  Migration

  Before:

  const { UserError, UserErr } = createTaggedError("UserError").withContext<{
    userId: string;
  }>();
  // ❌ Error: factories not available without .withMessage()

  After:

  const { UserError, UserErr } = createTaggedError("UserError")
    .withContext<{ userId: string }>()
    .withMessage(({ context }) => `User ${context.userId} failed`);
  // ✅ Factories now available