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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 Take-home Project rounds at Coinbase.

What role is this question designed for?

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

Design account opening workflow | Coinbase Interview Question

Quick Overview

This question evaluates a candidate's ability to architect a high-scale, secure, and regulated online account opening workflow, including API design, workflow orchestration, data modeling, PII protection, KYC/AML and sanctions integration, auditability, and operational reliability.

System Design: Online Bank Account Opening Workflow

Context

You are designing a high-scale online bank account opening workflow for web and mobile clients. The system must operate in a regulated environment, integrate with external KYC/AML and sanctions providers, and provide a secure, resilient, and auditable experience across multiple regions.

Requirements

Design the following:

APIs

Start a new application, save partial progress, submit, and resume an application.
Upload documents and verify them.
Provide real-time application status.

Workflow orchestration

Which steps are synchronous vs. asynchronous, and why.
How to model long-running tasks, callbacks, and manual review.

Correctness and safety

Idempotency and deduplication to prevent duplicate accounts.
Failure handling, retries, and exactly-once or at-least-once guarantees where appropriate.
Audit trails sufficient for regulatory compliance.

Data and security

Data model for Applicants, Applications, Documents, and related entities.
PII security: encryption, key management, access control, and safe logging.
Rate limiting and abuse controls.

Risk and compliance

KYC/AML and sanctions checks (and re-checks as needed).
Fraud/risk scoring and decisioning (auto-approve, reject, manual review).

Scale and reliability

Scale to millions of applications per day.
Multi-region architecture and data residency.

State any minimal assumptions you make.

Quick Overview

Requirements

Design the following:

APIs

Start a new application, save partial progress, submit, and resume an application.

Upload documents and verify them.

Provide real-time application status.

Workflow orchestration

Which steps are synchronous vs. asynchronous, and why.

How to model long-running tasks, callbacks, and manual review.

Correctness and safety

Idempotency and deduplication to prevent duplicate accounts.

Failure handling, retries, and exactly-once or at-least-once guarantees where appropriate.

Audit trails sufficient for regulatory compliance.

Data and security

Data model for Applicants, Applications, Documents, and related entities.

PII security: encryption, key management, access control, and safe logging.

Rate limiting and abuse controls.

Risk and compliance

KYC/AML and sanctions checks (and re-checks as needed).

Fraud/risk scoring and decisioning (auto-approve, reject, manual review).

Scale and reliability

Scale to millions of applications per day.

Multi-region architecture and data residency.

State any minimal assumptions you make.

Design account opening workflow

Quick Overview

System Design: Online Bank Account Opening Workflow

Context

Requirements

Solution

Comments (0)

Design account opening workflow

Quick Overview

System Design: Online Bank Account Opening Workflow

Context

Requirements

Solution

Comments (0)