The 3 Categories of Technical Knowledge and Skills

[RandintN]

The 3 Great Categories of Technical Challenges (and technical interviews)

Most of the time they will ask you WHAT [it is], so just memorize what the concepts below are.

The exception is Live Coding, where they want you to show how to implement them Live (with the screen shared), it's a matter of memorization too, this time, by typing the code you memorized.

They might ask you extra questions to fill the meeting time, again, previous memorization.

These are real questions my students and I received, nothing superficial generated by AI.

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1. Common Sense for DEVs

Design Patterns

- Singleton, Factory, Strategy, Decorator, Adapter, Facade, Observer, Command, Builder

Architectures

- Clean Architecture, Hexagonal, MVC, Event-Driven

Development Principles

- KISS, SOLID, DRY, YAGNI

Software Testing

- Unit, Integration, E2E, TDD (Test-Driven Development)

Version Control

- Git (main commands and concepts)

Live Coding

- Palindrome

- FizzBuzz

- String Manipulation (reverse, find duplicates, etc.)

Database Principles

- ACID, Normalization, Indexes, SQL vs NoSQL

Networks and Protocols

- HTTP (Verbs, Status Codes), RESTful, WebSockets

DevOps and CI/CD

- Docker (basics), Kubernetes (basics), CI/CD pipeline concept

Algorithms and Data Structures

- Big O Notation, Lists, Stacks, Queues, Trees, Graphs

Security

- OWASP Top Ten, SQL Injection, XSS

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2. Stack Details

Difference between StringBuffer and StringBuilder

- Thread-safety and synchronization (@synchronized)

- Performance and appropriate use

What is String Pool

- String interning in Java

- Benefits and usage considerations

Memory Management

- Heap and Stack

- Garbage Collection

- Young and Old Generation (G1GC Generational)

- Metaspace

- Scope of variables and lifecycle

Collections and Data Structures

- Lists, Sets, Maps

- Data structures: Stack, Queue, Tree, Graph

Concurrency and Multithreading

- Concurrency models

- Common problems: deadlock, livelock, starvation

- Synchronization tools

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3. Systems Design

Design Uber for Us

- General architecture and main components

- Location and mapping services

- Database and storage choice

- Scalability and load balancing

- Fault tolerance and high availability

- Security and authentication

Design an e-commerce

- Product catalog management

- Shopping cart and order processing

- [Other e-commerce components...]

Design a Social Media Platform

- [Components like news feed, user auth, media upload...]

Distributed Systems Design Patterns

- Microservices vs. Monoliths

- Communication Patterns (Sync, Async, Message Queues)

- Circuit Breaker

For a complete and updated list, read this document.