Microservices & Distributed Systems
Patterns, protocols, and practices for building resilient distributed systems — from API gateways to event-driven architecture.
Courses
Master how microservices talk to each other — synchronous REST and gRPC, async messaging, event-driven patterns, resilience, and distributed consistency.
Learn how to design scalable, reliable, and maintainable systems — from single servers to distributed architectures used by millions of users.
Articles
Traditional CRUD (Create, Read, Update, Delete) database architectures mutate entity records in place using SQL UPDATE queries. Destructivel…
Traditional enterprise microservices rely on multi-threaded shared-memory architectures where threads execute concurrent database transactio…
While traditional event streaming platforms like Apache Kafka store message logs directly on local broker disks, coupling message routing co…
In distributed storage systems, keeping data consistent across multiple independent server nodes in the presence of network partitions, hard…
Transitioning from monolithic database architectures to distributed microservices breaks traditional ACID database transactions. When an e-c…
In microservice architectures, inter-service communication network latency directly dictates overall user request response times. Traditiona…
Building modern interactive single-page applications (SPAs) often requires maintaining duplicate data models across frontend React/Vue codeb…
Selecting a messaging system for microservice communication involves balancing throughput, footprint complexity, and persistence guarantees.…
Executing long-running computations — such as generating PDF invoices, processing video uploads, or sending transactional email batches — in…
In microservices architectures, handling authentication, authorization, and rate limiting individually inside every backend service leads to…
Tightly coupled REST microservices introduce cascade failure risks: when one downstream service experiences an outage or latency spike, upst…
Traditional Java web applications rely on synchronous, blocking I/O models powered by the Servlet API (Tomcat, Jetty). Under high-concurrenc…
In cloud-native Kubernetes clusters, perimeter-only network security is insufficient. Once an attacker breaches the external API gateway or …
In enterprise .NET applications, traditional Create-Read-Update-Delete (CRUD) architectures suffer when handling complex domain business rul…
In microservices architectures, cascading failures present a constant operational threat. If a downstream payment gateway or third-party inv…
Tight coupling in REST and gRPC microservice architectures creates cascading service failures. If an Order Service calls payment, inventory,…
Traditional perimeter-based network security ('castle-and-moat') assumes that any service operating inside a private Virtual Private Cloud (…
Architecting multi-tenant Software-as-a-Service (SaaS) backend databases requires balancing strict data isolation against operational mainte…
Managing complex, high-frequency state updates in large React applications using traditional Redux or React Context leads to significant per…
As relational databases grow beyond millions to billions of rows, single-table query performance degrades due to massive B-Tree index sizes …
Relational databases like PostgreSQL excel at Online Transaction Processing (OLTP)—handling frequent single-row reads, updates, and inserts …
Traditional perimeter-based security ('Castle and Moat') assumes that all traffic inside a private network or Kubernetes cluster is inherent…
Selecting the correct authorization flow is essential for securing modern applications. The OAuth 2.1 specification consolidates OAuth 2.0 s…
Decoupling microservices using Event-Driven Architecture (EDA) requires choosing an asynchronous messaging backbone. Engineers evaluate thre…
Building multiplayer text editors like Google Docs, Figma, or Notion requires synchronizing concurrent modifications from multiple users acr…
Building fault-tolerant distributed databases requires keeping multiple server nodes synchronized on a sequence of state machine operations.…
Two background workers pick up the same financial payout job at the exact same millisecond. Without mutual exclusion across separate servers…
In high-concurrency microservices architectures, preventing race conditions when multiple stateless worker instances access shared resources…
At the heart of every database system lies a Storage Engine that determines how data is written to disk, indexed, and retrieved. Relational …
Rate Limiting is a critical defense mechanism for production APIs, protecting downstream microservices from traffic spikes, denial-of-servic…
Selecting the communication protocol between clients, API gateways, and internal microservices impacts API latency, payload sizes, developer…
System design interviews evaluate a candidate's ability to architect scalable, resilient, and cost-effective distributed systems under real-…
In-memory caching is an essential component of high-throughput web architectures, reducing database read load and accelerating API response …
Selecting the right primary database is one of the most critical architectural decisions for software teams. PostgreSQL is the world's most …
An order database's primary data center suffers a catastrophic, unrecoverable event — not a transient node failure, an actual disaster. Two …
A team deploys their application to three regions, each with its own app tier, database, and network path. On paper, a failure in one region…
A product-page personalization API needs to answer in under 100ms for a good user experience. A shopper in Sydney hits it, and the request h…
A multi-tenant analytics platform partitions incoming events by tenant_id, hashed onto 16 shards — a design that looked perfectly balanced i…
A URL shortener's redirect endpoint, GET /r/{code}, looks purely read-heavy — billions of redirects against a handful of short codes created…
An order service runs in two regions, us-east and eu-west. In one design, both regions serve live customer traffic right now, splitting the …
A permission check in front of a wire-transfer approval endpoint times out. What should happen next? One engineer's instinct says "don't blo…
A payment service keeps processing requests with zero dropped transactions while one of its three nodes crashes mid-request — that's fault t…
A product page shows the item, its price, and an "add to cart" button — the core path — plus a "customers also viewed" recommendation strip …
A checkout API runs three replicas across two availability zones behind a load balancer — on paper, no single point of failure. Then one AZ …
An order-ingestion API writes to an in-memory queue, a worker pool drains it, and a payment provider on the other end gets slow. The queue k…
A shopping cart write to cart-77 needs to land on enough replicas that a later read is guaranteed to see it — but "enough" is a number you c…
A 4-node session cache scales to 5 nodes to handle more traffic. With hash(key) % N, that single node addition changes almost every key's ta…
A user changes their display name, refreshes the page a second later from a phone on a different network, and sees the old name. Nothing cra…
A checkout API can wait until every step finishes, or accept an order and complete work later. The first path gives the caller an immediate …
A shopping cart must remember items, so the product cannot be literally stateless. The useful design question is where that state lives. Kee…
RabbitMQ is a broker: producers publish messages; exchanges route them; queues buffer work; consumers process and acknowledge. The same buil…
Many teams still introduce NGINX as “just a web server.” In production it usually sits in front of your app: clients hit NGINX first; your N…
Five Docker containers with REST between them is not a production microservices system. Clients hit a load balancer and API gateway; service…
Microservices are not a shopping list. They are a set of layers — package, store, communicate, protect the edge, run and observe — each with…
Mobile users lose signal in elevators, on flights, and in rural areas, but they still expect edits to survive. An offline-first architecture…
A customer sees “payment pending” after checkout, retries, and is charged twice. The design question is not whether the system uses fashiona…
Checkout hangs because payment is slow — and the order service is blocked waiting on a synchronous call. Event-driven architecture breaks th…
Every new project faces the same question: one deployable application or separately deployed services? A monolith minimizes distributed-syst…
Docker and Kubernetes are not competitors on the same layer, and treating them as an either/or is the mistake that leads teams to run a clus…
A checkout call may hit REST at the gateway, a GraphQL BFF for the mobile screen, gRPC between order and inventory, and a webhook when the p…
Asynchronous messaging decouples services in time — producers send without waiting for consumers. Kafka is a distributed event log for high-…
A trip booking needs a flight, a hotel room, and a card charge to either all succeed or all unwind — but each lives in a different service w…
A signup service inserts a new User row, then calls the broker to publish UserRegistered so the welcome-email and loyalty services can react…
An invoicing consumer reads InvoiceApproved from a queue, calls the payment processor to charge the card, and commits its offset. The broker…
A consumer service scales from two instances to eight expecting throughput to climb accordingly — instead, six of the eight sit idle while t…
Every request into a microservices backend crosses the same narrow point before it reaches any business logic: the API gateway. Under light …
A distributed lock feels like it should be enough: acquire it, do your write, release it, and only one client at a time gets to touch the re…
A WebSocket delivers every message reliably and in order over TCP — which sounds like exactly what a multiplayer game needs, until you reali…
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