Software Engineer Interview Prep

The Prep Cache

Last-minute prep for JavaScript

Practical interview prep and production lessons, distilled into short, high-signal notes. Built from real interviews and day-to-day engineering work.

Browse notes GitHub

Topics

Everything you might get asked, one branch at a time.

14 pages

System Design

HLD, LLD, case studies, machine coding, AI and frontend.

Open

11 pages

Frontend System Design

RADIO, rendering, Web Vitals, state, real-time and offline, micro-frontends, and 16 UI and app designs.

Open

2 pages

JavaScript

Async, event loop, closures, and tricky output questions.

Open

3 pages

TypeScript

Advanced types, generics, utility types, and design patterns.

Open

2 pages

React

Hooks, rendering, patterns, and performance.

Open

9 pages

React Native

New Architecture, navigation, lists, Reanimated, native modules, performance, and OTA releases.

Open

9 pages

Next.js

App Router, Server Components, caching, Server Actions, proxy, performance, and deployment.

Open

2 pages

Redux

Redux Toolkit, RTK Query, async flows, and state patterns.

Open

4 pages

DSA

14 interview patterns with templates and a playbook.

Open

9 pages

Backend

HTTP, APIs, auth, security, caching, queues, architecture, and deployment.

Open

10 pages

Databases

SQL, indexing, transactions, internals, NoSQL, sharding, and data modeling.

Open

8 pages

Networking

OSI and TCP/IP, subnetting, TCP and QUIC, DNS, HTTP, TLS, and troubleshooting.

Open

8 pages

Operating Systems

Processes, threads, scheduling, sync, deadlocks, memory, files, and Linux.

Open

6 pages

Computer Fundamentals

Number systems, architecture, caches, compilers, and how code runs.

Open

1 pages

Server-Driven UI

Architecture, component registries, versioning, React Native.

Open

1 pages

SDLC

Process models, Agile, Scrum, Kanban, DevOps, and CI/CD.

Open

3 pages

Java

Core language, collections, streams, concurrency, and JVM.

Open

9 pages

Python

Data model, decorators, generators, GIL, asyncio, typing, and output puzzles.

Open

1 pages

OOPS

Four pillars, SOLID principles, and design patterns.

Open

Short and dense

Each note is written to be skimmed. You can revise a whole topic in one sitting, not one weekend.

Diagrams over walls of text

473 flowcharts and diagrams show how each idea actually works, from the event loop to a full system design.

Code that runs

Java, JavaScript, and TypeScript snippets in the system design notes were compiled and run, not just typed.

Interview tomorrow?

Start from the tree, then search for whatever you forgot.

Open the tree