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MetaProduct SenseHard~25 min

WhatsApp Spam Detection

Duration
~25 minutes
Difficulty
Hard

WhatsApp is seeing a surge in spam messages across both individual and group chats. You've been asked to design a spam detection system. The catch: WhatsApp is end-to-end encrypted, which limits what data you can use.

Skills tested

System designPrivacy-constrained MLPrecision/recall tradeoffsMeasurement

Interview stages

  • 1Design the system
  • 2Precision vs. recall
  • 3Measure effectiveness
  • 4Encryption constraints

What you'll get back

After the session, you'll receive a detailed AI-generated debrief with stage-by-stage ratings (Strong / Developing / Weak), a signal coverage map showing which key points you hit, specific feedback on your reasoning and communication, and a reference response for comparison.

$3
One-time payment · No account required
  • ~25 minute AI-powered mock interview
  • Realistic interviewer pushback
  • Stage-by-stage debrief with ratings
  • Signal coverage map
  • Reference response for comparison

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