Code reviewHardcr-g093

Subject Partial failureLevel Senior–Staff~30 minCommon in Distributed systems interviewsIndustries Software development

Question

Review this JavaScript multi-write notifier.

What a strong answer looks like

Separate real bugs from style. Rank issues by severity, point at the root cause rather than the symptom, and suggest a concrete fix — specific and kind.

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Code to reviewjs

1async function notifyAll(userIds, message) {2  if (!userIds.length) return [];3  const results = await Promise.all(4    userIds.map((id) => pushService.send(id, message))5  );6  await db.markNotified(userIds);7  return results;8}9 10// caller11async function broadcast(segment, message) {12  const ids = await db.usersInSegment(segment);13  const sent = await notifyAll(ids, message);14  metrics.incr("push.sent", sent.length);15  return sent;16}

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