Distributed System interview questions

What is a distributed system?

Easy · Distributed System, Fundamentals, Fresher

The 8 fallacies of distributed computing

Easy · Distributed System, Fundamentals, Fresher

Monolith vs Distributed / Microservices

Easy · Distributed System, Fundamentals, Fresher

Scalability: vertical vs horizontal

Easy · Distributed System, Fundamentals, Fresher

Reliability vs Availability vs Durability

Easy · Distributed System, Fundamentals, Fresher

Fault vs Failure vs Error

Easy · Distributed System, Fundamentals, Fresher

Latency vs Throughput

Easy · Distributed System, Fundamentals, Fresher

RTT & Bandwidth-Delay Product

Easy · Distributed System, Networking, Fresher

Transparency types

Easy · Distributed System, Fundamentals, Fresher

Coupling & Cohesion

Easy · Distributed System, Scalability & Scenarios, Senior

Elasticity vs Scalability

Easy · Distributed System, Fundamentals, Fresher

SLA vs SLO vs SLI

Easy · Distributed System, Fundamentals, Fresher

Error budgets

Easy · Distributed System, Fundamentals, Fresher

Capacity planning basics

Easy · Distributed System, Fundamentals, Fresher

TCP vs UDP

Easy · Distributed System, Networking, Fresher

TCP 3-way handshake & 4-way termination

Easy · Distributed System, Networking, Fresher

HTTP/1.1 vs HTTP/2 vs HTTP/3

Easy · Distributed System, Networking, Fresher

HTTPS & TLS 1.3 handshake

Easy · Distributed System, Security, Fresher

DNS resolution flow

Easy · Distributed System, Networking, Fresher

Public IP, Private IP, NAT

Easy · Distributed System, Networking, Fresher

Ports & well-known port numbers

Easy · Distributed System, Networking, Fresher

CDN — what & why

Easy · Distributed System, Networking, Fresher

Forward vs Reverse proxy

Easy · Distributed System, Networking, Fresher

REST fundamentals

Easy · Distributed System, Fundamentals, Fresher

gRPC basics

Easy · Distributed System, Fundamentals, Fresher

GraphQL basics

Easy · Distributed System, Fundamentals, Fresher

WebSocket vs SSE vs Long-polling

Easy · Distributed System, Fundamentals, Fresher

HTTP status-code families

Easy · Distributed System, Fundamentals, Fresher

IPv4 vs IPv6

Easy · Distributed System, Networking, Fresher

Synchronous vs Asynchronous communication

Easy · Distributed System, Fundamentals, Fresher

Request-response vs Pub-Sub

Easy · Distributed System, Fundamentals, Fresher

Message queue vs Topic

Easy · Distributed System, Messaging & Streaming, Fresher

Point-to-point vs Fan-out / Fan-in

Easy · Distributed System, Fundamentals, Fresher

Event-driven architecture (EDA)

Easy · Distributed System, Fundamentals, Fresher

Orchestration vs Choreography

Easy · Distributed System, Distributed Transactions, Fresher

Streaming vs Batch processing

Easy · Distributed System, Fundamentals, Fresher

Unicast / Multicast / Broadcast / Anycast

Easy · Distributed System, Networking, Fresher

Callback vs Webhook

Easy · Distributed System, Fundamentals, Fresher

Push vs Pull

Easy · Distributed System, Fundamentals, Fresher

Backpressure basics

Easy · Distributed System, Fundamentals, Fresher

Idempotency intro

Easy · Distributed System, Fundamentals, Fresher

CAP theorem

Easy · Distributed System, CAP & Consistency, Fresher

ACID vs BASE

Easy · Distributed System, CAP & Consistency, Fresher

Strong vs Eventual consistency

Easy · Distributed System, CAP & Consistency, Fresher

Read-your-writes

Easy · Distributed System, CAP & Consistency, Fresher

Monotonic reads

Easy · Distributed System, CAP & Consistency, Fresher

Causal consistency

Easy · Distributed System, CAP & Consistency, Fresher

Session consistency

Easy · Distributed System, CAP & Consistency, Fresher

Replication overview

Easy · Distributed System, Replication & Partitioning, Fresher

Master-Slave (Leader-Follower) replication

Easy · Distributed System, Replication & Partitioning, Fresher

Quorum reads & writes

Easy · Distributed System, Replication & Partitioning, Fresher

Split-brain intro

Easy · Distributed System, Replication & Partitioning, Fresher

Isolation vs Consistency

Easy · Distributed System, Fundamentals, Fresher

What is caching & why

Easy · Distributed System, Fundamentals, Fresher

Prove the CAP theorem intuitively

Medium · Distributed System, CAP & Consistency, Senior

Common CAP misconceptions

Medium · Distributed System, CAP & Consistency, Senior

PACELC theorem

Medium · Distributed System, CAP & Consistency, Senior

Split-brain scenarios & prevention

Medium · Distributed System, Consensus & Coordination, Senior

Jepsen testing

Medium · Distributed System, CAP & Consistency, Senior

Types of network partitions

Medium · Distributed System, Networking, Senior

How to pick CP vs AP

Medium · Distributed System, CAP & Consistency, Senior

Harvest vs Yield

Medium · Distributed System, Fundamentals, Senior

Linearizability

Medium · Distributed System, CAP & Consistency, Senior

Sequential consistency

Medium · Distributed System, CAP & Consistency, Senior

Causal consistency (deep)

Medium · Distributed System, CAP & Consistency, Senior

Eventual consistency

Medium · Distributed System, CAP & Consistency, Senior

Bounded staleness

Medium · Distributed System, CAP & Consistency, Senior

Consistent prefix reads

Medium · Distributed System, CAP & Consistency, Senior

Read/Write quorum trade-offs

Medium · Distributed System, Replication & Partitioning, Senior

Cassandra tunable consistency

Medium · Distributed System, Fundamentals, Senior

DynamoDB consistency modes

Medium · Distributed System, Fundamentals, Senior

Session guarantees (Bayou)

Medium · Distributed System, CAP & Consistency, Senior

Monotonic writes

Medium · Distributed System, CAP & Consistency, Senior

Writes-follow-reads

Medium · Distributed System, CAP & Consistency, Senior

Synchronous vs Asynchronous replication (deep)

Medium · Distributed System, Replication & Partitioning, Senior

Chain replication

Medium · Distributed System, Replication & Partitioning, Senior

Multi-leader replication

Medium · Distributed System, Replication & Partitioning, Senior

Leaderless replication (Dynamo style)

Medium · Distributed System, Replication & Partitioning, Senior

Anti-entropy & Merkle trees

Medium · Distributed System, Replication & Partitioning, Senior

Read repair

Medium · Distributed System, Replication & Partitioning, Senior

Hinted handoff

Medium · Distributed System, Replication & Partitioning, Senior

Sloppy quorum

Medium · Distributed System, Replication & Partitioning, Senior

Conflict resolution: LWW & alternatives

Medium · Distributed System, Replication & Partitioning, Senior

Vector clocks

Medium · Distributed System, Fundamentals, Senior

Logical vs physical replication

Medium · Distributed System, Fundamentals, Senior

Replication lag remediation

Medium · Distributed System, Replication & Partitioning, Senior

Range vs Hash vs List partitioning

Medium · Distributed System, Replication & Partitioning, Senior

Consistent hashing (deep)

Medium · Distributed System, Replication & Partitioning, Senior

Virtual nodes (vnodes)

Medium · Distributed System, Replication & Partitioning, Senior

Hot partitions & mitigation

Medium · Distributed System, Replication & Partitioning, Senior

Online resharding

Medium · Distributed System, Replication & Partitioning, Senior

Secondary indexes: local vs global

Medium · Distributed System, Fundamentals, Senior

Cross-shard queries

Medium · Distributed System, Replication & Partitioning, Senior

Geo partitioning

Medium · Distributed System, Replication & Partitioning, Senior

Multi-tenant sharding strategies

Medium · Distributed System, Fundamentals, Senior

When to pick range vs hash

Medium · Distributed System, Replication & Partitioning, Senior

Rebalancing strategies

Medium · Distributed System, Replication & Partitioning, Senior

Consistent hash vs Jump hash vs Rendezvous

Medium · Distributed System, Replication & Partitioning, Senior

Two-Phase Commit (2PC)

Medium · Distributed System, Distributed Transactions, Senior

Three-Phase Commit (3PC)

Medium · Distributed System, Distributed Transactions, Senior

The blocking problem of 2PC

Medium · Distributed System, Distributed Transactions, Senior

XA transactions

Medium · Distributed System, Distributed Transactions, Senior

Saga (orchestration)

Medium · Distributed System, Distributed Transactions, Senior

Saga (choreography)

Medium · Distributed System, Distributed Transactions, Senior

TCC (Try-Confirm-Cancel)

Medium · Distributed System, Distributed Transactions, Senior

Outbox pattern

Medium · Distributed System, Distributed Transactions, Senior

Inbox pattern

Medium · Distributed System, Distributed Transactions, Senior

Transactional messaging

Medium · Distributed System, Messaging & Streaming, Senior

Designing compensating actions

Medium · Distributed System, Distributed Transactions, Senior

Raft internals: full state machine

Hard · Distributed System, Consensus & Coordination, Staff

Raft log truncation & snapshots

Hard · Distributed System, Consensus & Coordination, Staff

Basic Paxos in detail

Hard · Distributed System, Consensus & Coordination, Staff

Multi-Paxos

Hard · Distributed System, Consensus & Coordination, Staff

Fast Paxos

Hard · Distributed System, Consensus & Coordination, Staff

EPaxos (Egalitarian Paxos)

Hard · Distributed System, Consensus & Coordination, Staff

Cheap Paxos & Flexible quorums

Hard · Distributed System, Consensus & Coordination, Staff

ZAB (ZooKeeper Atomic Broadcast) in detail

Hard · Distributed System, Consensus & Coordination, Staff

Byzantine faults & PBFT

Hard · Distributed System, Consensus & Coordination, Architect

HotStuff / Tendermint

Hard · Distributed System, Consensus & Coordination, Architect

Raft vs Paxos — trade-offs

Hard · Distributed System, Consensus & Coordination, Staff

Membership changes (Raft joint consensus)

Hard · Distributed System, Consensus & Coordination, Staff

Google Spanner architecture

Hard · Distributed System, Scalability & Scenarios, Architect

CockroachDB architecture

Hard · Distributed System, Scalability & Scenarios, Architect

Amazon Aurora

Hard · Distributed System, Scalability & Scenarios, Staff

DynamoDB internals

Hard · Distributed System, Scalability & Scenarios, Staff

Cassandra internals

Hard · Distributed System, Scalability & Scenarios, Staff

HBase & Bigtable

Hard · Distributed System, Scalability & Scenarios, Staff

FoundationDB

Hard · Distributed System, Scalability & Scenarios, Architect

Chubby

Hard · Distributed System, Scalability & Scenarios, Architect

ZooKeeper deep

Hard · Distributed System, Scalability & Scenarios, Staff

etcd deep

Hard · Distributed System, Scalability & Scenarios, Staff

Kafka Controller / KRaft

Hard · Distributed System, Messaging & Streaming, Staff

TiDB / Vitess

Hard · Distributed System, Scalability & Scenarios, Staff

Linearizability — formal

Hard · Distributed System, CAP & Consistency, Staff

External consistency (Spanner)

Hard · Distributed System, CAP & Consistency, Staff

Snapshot Isolation (SI)

Hard · Distributed System, Scalability & Scenarios, Staff

Serializable Snapshot Isolation (SSI)

Hard · Distributed System, Scalability & Scenarios, Staff

State-based CRDTs (CvRDT)

Hard · Distributed System, Scalability & Scenarios, Staff

Operation-based CRDTs (CmRDT)

Hard · Distributed System, Scalability & Scenarios, Staff

Operational Transformation vs CRDT

Hard · Distributed System, Scalability & Scenarios, Staff

COPS & causal+ consistency

Hard · Distributed System, CAP & Consistency, Staff

Bayou

Hard · Distributed System, CAP & Consistency, Staff

Choosing consistency for geo replicas

Hard · Distributed System, CAP & Consistency, Architect

Percolator (Google 2010)

Hard · Distributed System, Distributed Transactions, Architect

Calvin

Hard · Distributed System, Distributed Transactions, Architect

Spanner transactions

Hard · Distributed System, Distributed Transactions, Staff

Deterministic transactions

Hard · Distributed System, Distributed Transactions, Staff

2PC failure modes (deep)

Hard · Distributed System, Distributed Transactions, Staff

Distributed lock — the Redlock debate

Hard · Distributed System, Scalability & Scenarios, Staff

Fencing tokens

Hard · Distributed System, Scalability & Scenarios, Staff

Saga pitfalls at scale

Hard · Distributed System, Distributed Transactions, Staff

TCC pitfalls

Hard · Distributed System, Distributed Transactions, Staff

Distributed deadlock detection

Hard · Distributed System, Distributed Transactions, Staff

TrueTime — full deep-dive

Hard · Distributed System, Scalability & Scenarios, Architect

Explain how DNS resolution works step by step.

Medium · Distributed System, DNS, Senior

What is the difference between recursive and iterative DNS queries?

Medium · Distributed System, DNS, Senior

What are common DNS record types (A, AAAA, CNAME, MX, TXT, SRV)?

Medium · Distributed System, DNS, Senior

How do DNS caching and TTL (Time-to-Live) impact performance?

Medium · Distributed System, DNS, Senior

How does Amazon Route 53 provide high availability and latency-based routing?

Medium · Distributed System, DNS, Senior

What is DNS poisoning/spoofing? How do you prevent it?

Medium · Distributed System, DNS, Senior

Explain how CDN providers integrate with DNS for load balancing.

Medium · Distributed System, DNS, Senior

Design a fault-tolerant DNS resolution system for a global e-commerce app.

Hard · Distributed System, DNS, Staff

What’s the difference between Layer 4 and Layer 7 load balancers?

Medium · Distributed System, Load Balancing, Senior

How does AWS ELB detect unhealthy instances and reroute traffic?

Medium · Distributed System, Load Balancing, Senior

Explain sticky sessions and when you’d use them.

Medium · Distributed System, Load Balancing, Senior

How would you design a load balancing strategy for a real-time chat system?

Hard · Distributed System, Load Balancing, Staff

What’s the role of reverse proxies like Nginx in load balancing?

Medium · Distributed System, Load Balancing, Senior

How do load balancers handle SSL/TLS termination?

Medium · Distributed System, Load Balancing, Senior

Explain how global load balancing differs from regional load balancing.

Medium · Distributed System, Load Balancing, Senior

How do you design a load balancer setup that supports disaster recovery?

Hard · Distributed System, Load Balancing, Staff

Compare SQL vs NoSQL databases and when to use each.

Medium · Distributed System, Database, Senior

How does database replication improve availability?

Medium · Distributed System, Database, Senior

How do sharding and partitioning differ?

Medium · Distributed System, Database, Senior

Explain CAP theorem and its application in database systems.

Medium · Distributed System, Database, Senior

How does DynamoDB achieve horizontal scalability?

Medium · Distributed System, Database, Senior

Design a schema for a high-volume transaction system (like UPI).

Hard · Distributed System, Database, Staff

How do you handle database migration in production without downtime?

Medium · Distributed System, Database, Senior

How do Redis and DynamoDB differ in design and use cases?

Hard · Distributed System, Key-Value Store, Staff

What are typical eviction policies in Redis?

Medium · Distributed System, Key-Value Store, Senior

How do you ensure consistency in a distributed key-value store?

Medium · Distributed System, Key-Value Store, Senior

Explain write-through, write-back, and write-around caching strategies.

Medium · Distributed System, Key-Value Store, Senior

Design a leaderboard system using Redis sorted sets.

Hard · Distributed System, Key-Value Store, Staff

How do you prevent cache stampede and thundering herd problems?

Medium · Distributed System, Key-Value Store, Senior

How do you secure Redis or DynamoDB in production?

Medium · Distributed System, Key-Value Store, Senior

How does a CDN reduce latency for end users?

Medium · Distributed System, CDN, Senior

How do you handle cache invalidation in CDN?

Medium · Distributed System, CDN, Senior

Explain edge caching and its importance in video streaming.

Medium · Distributed System, CDN, Senior

How does Cloudflare handle DDoS protection via CDN?

Medium · Distributed System, CDN, Senior

Design a global CDN strategy for an OTT video platform.

Hard · Distributed System, CDN, Staff

What are challenges in serving dynamic vs static content via CDN?

Medium · Distributed System, CDN, Senior

Why do distributed systems need a sequencer?

Medium · Distributed System, Sequencer, Senior

Explain Twitter’s Snowflake ID generator design.

Hard · Distributed System, Sequencer, Staff

What are trade-offs between UUID and Snowflake IDs?

Medium · Distributed System, Sequencer, Senior

How do you design a sequencer to avoid collisions in a high-scale system?

Hard · Distributed System, Sequencer, Staff

How do sequencers preserve causality in event processing?

Medium · Distributed System, Sequencer, Senior

What are scalability challenges in a centralized sequencer?

Medium · Distributed System, Sequencer, Senior

How do you implement distributed ID generation in DynamoDB?

Medium · Distributed System, Sequencer, Senior

What are key metrics to monitor in distributed systems?

Medium · Distributed System, Monitoring, Senior

How do you implement health checks in microservices?

Medium · Distributed System, Monitoring, Senior

What is the difference between master-slave and master-master replication?

Medium · Distributed System, Database, Senior

What's the difference between strong and eventual consistency in key-value stores?

Medium · Distributed System, Key-Value Store, Senior

What's the difference between push CDN and pull CDN?

Easy · Distributed System, CDN, Fresher

What's the difference between black-box and white-box monitoring?

Easy · Distributed System, Monitoring, Fresher

Explain Prometheus pull vs push metrics collection.

Medium · Distributed System, Monitoring, Senior

How do you design an alerting system to avoid alert fatigue?

Medium · Distributed System, Monitoring, Senior

How does AWS CloudWatch integrate with auto-scaling?

Medium · Distributed System, Monitoring, Senior

What is the difference between logging, monitoring, and observability?

Easy · Distributed System, Monitoring, Fresher

Why do we need distributed caching instead of local cache?

Easy · Distributed System, Distributed Caching, Fresher

How does Redis cluster ensure partition tolerance?

Medium · Distributed System, Distributed Caching, Senior

What are cache invalidation strategies?

Medium · Distributed System, Distributed Caching, Senior

Explain cache-aside vs read-through caching.

Easy · Distributed System, Distributed Caching, Fresher

Design a caching strategy for an e-commerce product catalog.

Medium · Distributed System, Distributed Caching, Senior

How do you ensure consistency in multi-node cache clusters?

Hard · Distributed System, Distributed Caching, Staff

What are common pitfalls of caching (e.g., stale data, cache stampede)?

Medium · Distributed System, Distributed Caching, Senior

Compare Kafka vs RabbitMQ vs AWS SQS.

Medium · Distributed System, Messaging & Streaming, Senior

How does Kafka ensure message durability?

Medium · Distributed System, Messaging & Streaming, Senior

What is the difference between at-most-once, at-least-once, and exactly-once delivery?

Medium · Distributed System, Messaging & Streaming, Senior

How does partitioning work in Kafka?

Medium · Distributed System, Messaging & Streaming, Senior

Design a messaging system for order processing in e-commerce.

Hard · Distributed System, Messaging & Streaming, Staff

What are dead-letter queues (DLQs) and when do you use them?

Easy · Distributed System, Messaging & Streaming, Fresher

How do you handle backpressure in message queues?

Medium · Distributed System, Messaging & Streaming, Senior

How does pub-sub differ from point-to-point messaging?

Easy · Distributed System, Pub-Sub, Fresher

Explain fan-out in pub-sub systems.

Easy · Distributed System, Pub-Sub, Fresher

What challenges arise in maintaining message ordering in pub-sub?

Medium · Distributed System, Pub-Sub, Senior

How does Google Pub/Sub scale globally?

Medium · Distributed System, Pub-Sub, Senior

Design an event-driven architecture using SNS + SQS + Lambda.

Hard · Distributed System, Pub-Sub, Staff

What's the role of Kafka topics and consumer groups in pub-sub?

Medium · Distributed System, Pub-Sub, Senior

Why do we need rate limiting in APIs?

Easy · Distributed System, Rate Limiting, Fresher

Compare token bucket vs leaky bucket algorithms.

Medium · Distributed System, Rate Limiting, Senior

How does API Gateway in AWS implement rate limiting?

Medium · Distributed System, Rate Limiting, Senior

Design a rate limiter for login attempts in a banking app.

Hard · Distributed System, Rate Limiting, Staff

How do you prevent abuse when scaling rate limiters across multiple servers?

Hard · Distributed System, Rate Limiting, Staff

What's the role of Redis in implementing distributed rate limiting?

Medium · Distributed System, Rate Limiting, Senior

How does Elasticsearch index data?

Medium · Distributed System, Distributed Search, Senior

What's the difference between inverted index and forward index?

Easy · Distributed System, Distributed Search, Fresher

How does distributed search handle sharding and replication?

Medium · Distributed System, Distributed Search, Senior

Explain full-text search vs keyword search.

Easy · Distributed System, Distributed Search, Fresher

Design a search engine for an e-commerce platform.

Hard · Distributed System, Distributed Search, Staff

What are common scaling challenges with Elasticsearch?

Medium · Distributed System, Distributed Search, Senior

How do you implement autocomplete efficiently in search?

Medium · Distributed System, Distributed Search, Senior

Why is centralized logging important in microservices?

Easy · Distributed System, Distributed Logging, Fresher

How does ELK stack (Elasticsearch, Logstash, Kibana) work together?

Medium · Distributed System, Distributed Logging, Senior

What's the difference between structured and unstructured logs?

Easy · Distributed System, Distributed Logging, Fresher

How do you design a log aggregation system for 1M+ events/sec?

Hard · Distributed System, Distributed Logging, Staff

What are common challenges in log storage and retention?

Medium · Distributed System, Distributed Logging, Senior

How does CloudWatch Logs differ from Splunk?

Medium · Distributed System, Distributed Logging, Senior

What problem does distributed tracing solve?

Easy · Distributed System, Distributed Tracing, Fresher

Explain how AWS X-Ray works.

Medium · Distributed System, Distributed Tracing, Senior

What are spans and traces in OpenTelemetry?

Easy · Distributed System, Distributed Tracing, Fresher

How do you trace a request across multiple microservices?

Medium · Distributed System, Distributed Tracing, Senior

Design a tracing setup for a large-scale payments platform.

Hard · Distributed System, Distributed Tracing, Staff

What are challenges in tracing asynchronous calls?

Medium · Distributed System, Distributed Tracing, Senior

What's the difference between cron jobs and distributed schedulers?

Easy · Distributed System, Task Scheduling, Fresher

How does Apache Airflow manage DAG dependencies?

Medium · Distributed System, Task Scheduling, Senior

How do AWS Step Functions handle retries and rollbacks?

Medium · Distributed System, Task Scheduling, Senior

Design a scheduling system for nightly ETL jobs processing TBs of data.

Hard · Distributed System, Task Scheduling, Staff

What challenges arise in distributed task scheduling across regions?

Hard · Distributed System, Task Scheduling, Staff

How do you handle idempotency in scheduled tasks?

Medium · Distributed System, Task Scheduling, Senior

What's the difference between object storage and block storage?

Easy · Distributed System, Blob Storage, Fresher

How does S3 achieve 11 9's durability?

Medium · Distributed System, Blob Storage, Senior

Explain eventual consistency in S3 read-after-write model.

Medium · Distributed System, Blob Storage, Senior

How do you secure access to blob storage in cloud?

Medium · Distributed System, Blob Storage, Senior

Design a storage strategy for a video streaming platform.

Hard · Distributed System, Blob Storage, Staff

What's the difference between hot, warm, and cold storage tiers?

Easy · Distributed System, Blob Storage, Fresher

How do you handle data lifecycle management in blob storage?

Medium · Distributed System, Blob Storage, Senior

Stateless vs stateful services — why does it matter for scaling?

Easy · Distributed System, Fundamentals, Fresher

What is connection pooling and why is it critical in distributed systems?

Easy · Distributed System, Fundamentals, Fresher

How do retries with exponential backoff and jitter work?

Easy · Distributed System, Fundamentals, Fresher

How do you implement pagination in distributed APIs?

Easy · Distributed System, Fundamentals, Fresher

Explain the circuit breaker pattern in distributed systems.

Medium · Distributed System, Fundamentals, Senior

What is the bulkhead pattern and when do you use it?

Medium · Distributed System, Fundamentals, Senior

How does service discovery work in distributed systems?

Medium · Distributed System, Fundamentals, Senior

What is the API Gateway pattern in distributed architectures?

Medium · Distributed System, Fundamentals, Senior

How do you implement graceful shutdown in distributed services?

Easy · Distributed System, Fundamentals, Senior

What is leader election and when is it needed?

Medium · Distributed System, Fundamentals, Senior

What are Bloom filters and how are they used in distributed systems?

Medium · Distributed System, Fundamentals, Senior

Explain gossip protocols in distributed systems.

Medium · Distributed System, Fundamentals, Senior

How do you achieve exactly-once processing in distributed systems?

Hard · Distributed System, Messaging & Streaming, Senior

What is Change Data Capture (CDC) and how is it used?

Medium · Distributed System, Messaging & Streaming, Staff

What are security fundamentals for distributed systems?

Medium · Distributed System, Security, Senior

How does mTLS secure service-to-service communication?

Medium · Distributed System, Security, Senior

What is chaos engineering and how do you practice it safely?

Medium · Distributed System, Observability, Staff

Design a URL shortener (TinyURL) at scale.

Hard · Distributed System, Scalability & Scenarios, Fresher

Design a distributed rate limiter.

Hard · Distributed System, Scalability & Scenarios, Fresher

Design a notification system (push, email, SMS).

Medium · Distributed System, Scalability & Scenarios, Senior

Design a news feed system (Twitter/Instagram style).

Hard · Distributed System, Scalability & Scenarios, Senior

Design a distributed cache like Redis Cluster.

Hard · Distributed System, Scalability & Scenarios, Senior

Design a distributed job scheduler.

Hard · Distributed System, Scalability & Scenarios, Senior

Design a distributed payment system with strong consistency.

Hard · Distributed System, Scalability & Scenarios, Staff

Design a global payment platform for a bank (Staff/Architect level).

Hard · Distributed System, Scalability & Scenarios, Architect

Compare active-active vs active-passive multi-region architecture.

Medium · Distributed System, Operations & Reliability, Staff

Explain RPO and RTO in disaster recovery.

Easy · Distributed System, Operations & Reliability, Staff

How do feature flags enable gradual rollout in distributed systems?

Medium · Distributed System, Operations & Reliability, Staff

Compare blue-green and canary deployments.

Medium · Distributed System, Operations & Reliability, Staff

What is the strangler fig pattern for system migration?

Medium · Distributed System, Operations & Reliability, Staff

How do you manage dependencies and blast radius in distributed systems?

Medium · Distributed System, Operations & Reliability, Staff

How do you optimize cost in large-scale distributed systems?

Medium · Distributed System, Operations & Reliability, Staff

How does clock skew affect distributed systems and how do you handle it?

Medium · Distributed System, Operations & Reliability, Senior

What is event sourcing in distributed systems?

Medium · Distributed System, Architecture & Strategy, Staff

Explain the CQRS pattern and when to use it.

Medium · Distributed System, Architecture & Strategy, Staff

What is a service mesh and what problems does it solve?

Medium · Distributed System, Architecture & Strategy, Staff

What is zero-trust architecture in distributed systems?

Hard · Distributed System, Architecture & Strategy, Architect

How does Domain-Driven Design (bounded contexts) apply to distributed systems?

Medium · Distributed System, Architecture & Strategy, Architect

How do you decide build vs buy for distributed infrastructure components?

Medium · Distributed System, Architecture & Strategy, Architect

What is data mesh and how does it differ from a centralised data platform?

Hard · Distributed System, Architecture & Strategy, Architect

What are trade-offs of multi-cloud distributed architecture?

Hard · Distributed System, Architecture & Strategy, Architect

What is platform engineering and how does it support distributed teams?

Medium · Distributed System, Architecture & Strategy, Architect

Design a company-wide event backbone for distributed systems.

Hard · Distributed System, Architecture & Strategy, Architect

How do compliance and data residency affect distributed architecture?

Medium · Distributed System, Architecture & Strategy, Architect

What is evolutionary architecture for distributed systems?

Medium · Distributed System, Architecture & Strategy, Architect