The WhatsApp team is discussing: should we implement cloud backup with slower restore times or local backup with quicker recovery?

Introduction

The WhatsApp team is facing a critical decision: should we implement cloud backup with slower restore times or local backup with quicker recovery? This trade-off involves balancing user experience, data security, and technical considerations. I'll analyze this problem by examining the product context, identifying key metrics, designing experiments, and providing a data-driven recommendation.

Step 1

Clarifying Questions (3 minutes)

• Based on WhatsApp's global user base, I'm thinking data privacy regulations might be a key factor. Could you provide insights on our current compliance status across different regions?

Why it matters: Helps determine feasibility of cloud backup in various markets Expected answer: Varying compliance levels across regions Impact on approach: May need to consider region-specific backup solutions

• Considering user behavior, I'm assuming message history is crucial for many users. What percentage of our users regularly use the existing backup feature?

Why it matters: Indicates importance of backup functionality to our user base Expected answer: High usage, possibly 70-80% of active users Impact on approach: High usage would prioritize reliability over speed

• Looking at technical constraints, I'm wondering about our current server capacity. How much additional load can our infrastructure handle for cloud backups?

Why it matters: Determines feasibility and cost of cloud backup implementation Expected answer: Moderate capacity available, but significant investment needed for full rollout Impact on approach: May need to consider phased implementation or hybrid solution

• Regarding our product roadmap, I'm curious about upcoming features that might affect backup needs. Are there any major changes planned that could impact data volume or backup frequency?

Why it matters: Ensures our backup solution is future-proof Expected answer: Plans for increased media sharing or new content types Impact on approach: Might influence choice between scalable cloud solution vs. limited local storage