How do I approach System Design interview questions?

System Design questions require understanding of core concepts and practice. PracHub provides solutions with explanations to help you master system design interviews.

What difficulty level is this interview question?

This is a hard difficulty System Design question, commonly asked during Onsite rounds at Remitly.

What role is this question designed for?

This question is commonly asked for Software Engineer candidates at Remitly during technical interviews.

Whiteboard and Deep Dive a Past Project | Remitly Interview Question

Quick Overview

This question evaluates a candidate's end-to-end system design skills, including architecture decomposition, trade-off analysis, data consistency choices, scalability and resiliency patterns, and integration of operational practices for a user-facing distributed service.

System Design: End-to-End Architecture Walkthrough

Prompt

Whiteboard the end-to-end architecture of a complex, user-facing system you led. Cover:

Major components and their responsibilities.
Data flows and key interactions (happy-path and failure-path).
Storage choices and data models (including consistency needs).
External dependencies and how you integrated with them.
Key trade-offs (e.g., consistency vs. availability, latency vs. cost).
Scaling strategy and failure recovery/resiliency patterns.
Testing, monitoring/alerting, and iteration practices.
What you would change if you rebuilt it today.

Minimal Context (to keep the exercise concrete)

Assume a high-availability, low-latency service with the following example constraints:

p99 latency: ≤ 300 ms for synchronous APIs.
Availability: ≥ 99.95%.
Peak load: ~2,000 requests/sec (bursty), average ~300 requests/sec.
Multi-region read traffic; write traffic primarily in one region initially.
Mix of strongly consistent operations (e.g., money movement, ledgers) and eventually consistent operations (e.g., analytics, notifications).

If you don't have a past project that fits, you may use a representative example such as "Real-time transaction authorization and settlement" or "High-traffic quotes and checkout service."

Quick Overview

Prompt

Whiteboard the end-to-end architecture of a complex, user-facing system you led. Cover:

Major components and their responsibilities.

Data flows and key interactions (happy-path and failure-path).

Storage choices and data models (including consistency needs).

External dependencies and how you integrated with them.

Key trade-offs (e.g., consistency vs. availability, latency vs. cost).

Scaling strategy and failure recovery/resiliency patterns.

Testing, monitoring/alerting, and iteration practices.

What you would change if you rebuilt it today.

Minimal Context (to keep the exercise concrete)

Assume a high-availability, low-latency service with the following example constraints:

p99 latency: ≤ 300 ms for synchronous APIs.

Availability: ≥ 99.95%.

Peak load: ~2,000 requests/sec (bursty), average ~300 requests/sec.

Multi-region read traffic; write traffic primarily in one region initially.

Mix of strongly consistent operations (e.g., money movement, ledgers) and eventually consistent operations (e.g., analytics, notifications).

If you don't have a past project that fits, you may use a representative example such as "Real-time transaction authorization and settlement" or "High-traffic quotes and checkout service."

Whiteboard and Deep Dive a Past Project

Quick Overview

System Design: End-to-End Architecture Walkthrough

Prompt

Minimal Context (to keep the exercise concrete)

Solution

Submit Your Answer to Earn 20XP

Whiteboard and Deep Dive a Past Project

Quick Overview

System Design: End-to-End Architecture Walkthrough

Prompt

Minimal Context (to keep the exercise concrete)

Solution

Submit Your Answer to Earn 20XP