Interview study that behaves like a roadmap, not a blog.

Capacity, trade-offs, and request paths you can defend on a whiteboard.

rate-limiting · sharding · queues

HTTP semantics, retries, idempotency, GraphQL tradeoffs, and contract design.

http · rest · graphql · idempotency

Latency wins, stampede control, and invalidation that does not lie.

redis · ttl · cache-aside

Indexes, isolation, storage engines, shard and partition keys, and zero-downtime migrations you can ship without a maintenance window.

indexes · transactions · storage · migrations · partitioning · shard-keys

TCP, TLS, load balancers, and why the p99 lives in the handshake.

tcp · tls · lb

Locks, isolation, and the bugs that only show up in production.

locks · async · races

SLIs, traces, and the dashboard you would actually page on.

metrics · tracing · sli

Retrieval, embeddings, vector indexes, evals, and serving patterns for senior interviews.

rag · embeddings · evals · serving

Query plans, joins, and the index the interviewer hopes you mention.

joins · plans · window-functions

Kafka, event-driven architecture, outbox and CQRS, WebSockets, MQTT, and queues you can defend in interviews.

kafka · eda · outbox · queues

Pipelines, sketches, approximate aggregations, object storage, and stream processing with event time, windows, and exactly-once sinks.

sketches · pipelines · aggregations · object-storage · stream-processing

Raft consensus, replication, consistent hashing, saga-style distributed transactions, two-phase commit, and conflict-free replicated data types.

raft · consensus · replication · sagas · two-phase-commit · crdt

AuthN, AuthZ, OAuth/OIDC, OWASP web attacks (injection, XSS, CSRF, SSRF, CORS), secrets/KMS, tokens, and service identity you can defend in interviews.

oauth · oidc · jwt · mtls · authz · secrets · kms

Kubernetes workloads, CI/CD pipelines, artifact digests, supply-chain controls, Git rebase, merge, and recovery, and Terraform state, modules, and safe change you can defend in interviews.

kubernetes · deployments · probes · rollouts · cicd · supply-chain · git · terraform · iac

Profiling, flame graphs, latency budgets, and load tests you can defend in interviews.

profiling · flame-graphs · latency · p99

Pyramid, contracts, property-based tests, doubles, and flakes you can defend in interviews.

test-pyramid · contracts · property-based · flakes

Interview pattern map — arrays to DP/backtracking — with Big-O, templates, and LeetCode drills.

dsa · algorithms · leetcode · patterns · big-o

Browser and PWA internals: service workers, the rendering pipeline, and the multi-process model you can defend in interviews.

pwa · service-workers · browser-engines · rendering

JavaScript, Python, Rust, and Go runtimes, plus TypeScript and Python typing: ownership, event loops, the GIL, goroutines, and packaging.

javascript · python · rust · go

Timed interview debugging: find the signal, reproduce, ship the smallest fix, then design one component.

debugging · cloudwatch · interview

Virtual memory, paging, the page cache, and Linux I/O models: blocking calls, epoll, io_uring, and event-loop backpressure.

virtual-memory · paging · tlb

HLD interview and machine-coding scale-up: capacity, APIs, data model, caching, sharding, and the path from a single-node solution to production.

hld · url-shortener · system-design · machine-coding

OOP and SOLID class design for machine-coding LLD: interfaces, invariants, in-memory state, and concurrency you can implement and test.

lld · ood · machine-coding · concurrency

RTO and RPO, backups and PITR, multi-region failover, and cells with static stability you can defend in interviews.

disaster-recovery · rto · rpo · multi-region · failover