Backend Developer Interview

Technical Discussion Questions

About This Interview

These questions focus on backend development challenges you might encounter while building a multi-tenant WhatsApp automation platform for businesses.

We're interested in your thought process, problem-solving approach, and technical reasoning rather than perfect answers.

Duration: 30-45 minutes | Format: Technical discussion with examples

1

Multi-Tenant Data Isolation

We have 50+ gym and trek companies using our platform. If Gym A sends a WhatsApp message, how would you ensure their conversation data never accidentally shows up in Gym B's dashboard? Walk me through your database design.
2

WhatsApp Webhook Performance

WhatsApp expects us to respond to webhooks within 5 seconds or they'll retry. If we need to generate a trek itinerary PDF, qualify a lead, and send a response - how do you handle this without timing out?
3

Real-World Debugging

A gym owner calls saying 'My WhatsApp bot is responding to trek messages instead of gym messages.' Your logs show the tenant_id is correct. What could be wrong and how do you debug this?
4

Database Schema Design

Different gyms want different membership plans - some have 3 plans, others have 10. Trek companies have different difficulty levels and group sizes. How do you design a flexible database schema for this?
5

API Design Under Load

We're processing 1000+ WhatsApp messages per minute across all tenants. Your API endpoint is getting slow. How do you identify the bottleneck and fix it?