What is QuizBytesDaily?

QuizBytesDaily posts bite-sized tech quiz Shorts every day on YouTube. Each video is under 60 seconds and covers Python, AI, Algorithms, System Design, or JavaScript.

How can I test my tech knowledge?

Visit quizbytes.dev to play interactive tech quizzes for free, or subscribe on YouTube to get a new quiz Short every day.

What topics are covered?

Python, AI/ML, Algorithms, Data Structures, JavaScript, TypeScript, System Design, DevOps, and more.

System Design Quiz — Test Your Architecture Knowledge

About System Design Quizzes

System design is the discipline of architecting software systems that are scalable, reliable, maintainable, and cost-effective. Unlike coding problems, system design has no single correct answer — it requires weighing trade-offs: consistency vs. availability, latency vs. throughput, simplicity vs. flexibility.

QuizBytesDaily's system design quizzes translate abstract principles into concrete questions. What consistency guarantees does a relational database provide that a document store doesn't? When should you prefer a message queue over a direct HTTP call? What is the practical difference between horizontal and vertical scaling? How do CDNs work, and what are their failure modes?

We cover the building blocks every senior engineer must know: load balancers, caches (Redis, Memcached), relational and NoSQL databases, message queues (Kafka, RabbitMQ), CDNs, API gateways, service meshes, and observability tooling. We also cover the theoretical foundations: the CAP theorem, PACELC, eventual consistency, consensus algorithms, and the two generals' problem.

Why Learn System Design?

Senior-level interviews

System design rounds are mandatory at senior+ levels at all major tech companies. Structured daily practice builds the vocabulary and intuition you need.

Make better architectural decisions

Every engineering decision is a design decision. Understanding the trade-offs at a systems level helps you propose and evaluate solutions more rigorously.

Communicate with your team

System design vocabulary — idempotency, eventual consistency, back-pressure — is the lingua franca of senior engineering discussions.

What You'll Find in Our System Design Quizzes

✓CAP theorem, PACELC, and consistency models
✓Database choices: RDBMS, NoSQL, NewSQL, time-series
✓Caching strategies: write-through, write-back, cache-aside, CDN
✓Message queues: Kafka partitions, consumer groups, at-least-once delivery
✓Load balancing: L4 vs L7, sticky sessions, health checks
✓Microservices: service discovery, circuit breakers, API gateways
✓Rate limiting, back-pressure, and bulkhead patterns

Other Quiz Categories

🐍 Python 🤖 AI & Machine Learning 🧮 Algorithms ⚡ JavaScript 📘 TypeScript

Sample System Design Quiz Questions

A taste of what you'll find in the System Design quiz series.

According to the CAP theorem, which two properties can a distributed system guarantee simultaneously during a network partition?

A.Consistency and Availability

B.Availability and Partition tolerance

C.Consistency and Partition tolerance✓ Correct

D.All three: Consistency, Availability, and Partition tolerance

Explanation: The CAP theorem states that during a network partition, a distributed system can provide either Consistency (every read returns the most recent write) OR Availability (every request gets a non-error response), but not both. Partition tolerance (the system continues despite network failures between nodes) is non-optional in any real distributed system — network failures happen. Systems like HBase and ZooKeeper choose CP; Cassandra and CouchDB choose AP.

What is the key difference between a cache 'write-through' and 'write-back' strategy?

A.Write-through updates the cache only; write-back updates both cache and database

B.Write-through updates both cache and database synchronously; write-back writes to cache immediately and database asynchronously✓ Correct

C.Write-through is used for reads; write-back is used for writes

D.There is no difference — the terms are interchangeable

Explanation: Write-through: every write updates the cache and the database synchronously before acknowledging the write to the client. This ensures consistency but adds write latency. Write-back (write-behind): writes go to the cache immediately, and the cache asynchronously flushes to the database later. This gives much lower write latency but risks data loss if the cache node fails before the flush. Write-back is used where write throughput matters more than strict durability.

What does a circuit breaker pattern do in a microservices architecture?

A.Encrypts traffic between services to prevent data leaks

B.Balances load across service instances using round-robin

C.Stops calls to a failing downstream service to prevent cascading failures, then periodically retries✓ Correct

D.Caches responses from downstream services to reduce latency

Explanation: A circuit breaker wraps calls to an external service. When the failure rate exceeds a threshold, the breaker trips to 'open' state and immediately rejects further calls without attempting the network request. After a timeout (half-open state), it allows a probe request through. If the probe succeeds, the breaker resets to closed; if it fails, the breaker stays open. This prevents a slow or failed dependency from consuming all threads and crashing the calling service.