arialdomartini / Back-End-Developer-Interview-Questions

Back-End Developer Interview Questions ====================================== This page has been translated to Chinese by monklof. I started writing down this list as my personal notes of topics I discussed with colleagues and friends, and that I wanted to deepen... I'm not a big fan of asking technical questions in job interviews: I rather prefer to sit together with candidates in front of some real code, hands on the keyboard, facing a real problem, and to have a full day of pair programming, hopefully rotating with all the other team members. It is one of the best opportunities to know each others' style and to let candidates know some details about their future job. Yet, I feel some categories of technical questions could be a good starting point to begin an engaging conversation. This repo collects a number of back-end related questions that can be used when vetting potential candidates. It is by no means recommended to use every single question on the same candidate: that would take hours, and would have no sense at all, as they cover a too broad set of topics for a single developer's to possibly know. Browse the section you find more relevant for your context, and pick the questions that give you more ideas on the conversation to have. This project is admittedly inspired by Front-end Job Interview Questions by @darcyclarke Where are the answers? I didn't include any. Most of the questions are open-ended, and some of them just don't have a *right* or a *wrong* answer. On the contrary, they are intended to be used as the starting point for a conversation that hopefully tells you more about the person's capabilities than a straight answer would. Personally, I would even choose the questions whose answers are not yet clear to me. Feel free to open a Discussion. Table of Contents • Questions about Design Patterns • Globals Are Evil • Inversion of Control • Law of Demeter • Active-Record • Data-Mapper • Billion-Dollar Mistake • Inheritance vs Composition • Anti-Corruption Layer • Singleton • Data Abstraction • Don't Repeat Yourself • Dependency Hell • Goto Is Evil • Robustness Principle • Separation of Concerns • Questions about Code Design • High Cohesion, Loose Coupling • Index 0 • TDD • DRY Violation • Cohesion vs Coupling • Refactoring • Code Comments • Design vs Architecture • Early Testing • Multiple Inheritance • Domain Logic in Stored Procedures • OOP Took Over the World • Bad Design • Questions about languages • 3 Worst Defects • Functional Programming • Closures • Generics • High-Order Functions • Loops and Recursion • Functions as First-Class Citizens • Anonymous Functions • Static and Dynamic Typing • Namespaces • Language Interoperability • Hate of Java • Good and Bad Languages • Referential Transparency • Stack and Heap • Pattern Matching • Exceptions • Variant and Contravariant Inheritance • Constructors and Interfaces • Node.js • Java and Time Traveling • Eliminate Null • Web Questions • 3rd Party Cookies • API Versioning • SPAs • Statelessness • REST vs SOAP • MVC and MVVM • Databases Questions • DB Migrations • NULL is special • ACID • Schema Migrations • Lazy Loading • N+1 Problem • Slowest Queries • Normalization • Blue/Green Deployment • NoSQL Questions • Eventual Consistency • CAP Theorem • NoSql • NoSQL and Scalability • Document and Relational DBs • Code Versioning Questions • Branching in HG and in Git • DVCS • GitFlow and GitHubFlow • Rebase • Merging in HG and in Git • Questions about Concurrency • Why? • Testing Concurrency • Race Conditions • Deadlocks • Process Starvation • Free Algorithm • Questions about Distributed Systems • Testing Distributed Systems • Async Communication • Pitfalls of RPC • Design of Distributed Systems • Fault Tolerance • Failures • Network Partitions • Fallacies of Distributed Computing • Request/Reply vs Publish/Subscribe • Implement Transactions • Questions about Software Lifecycle and Team Management • Agility • Legacy Code • Legacy Code ELI5 • Sell me Kanban • Agile vs Waterfall • Death by Meetings • Late Projects • Agile Manifesto • If I were the CTO • PMs • Team Organization • Turn Over • Qualities • 3 Things About Code • 1 Month's Revolution • Questions about logic and algorithms • FIFO with LIFO • Stack Overflow • Tail Recursive n! • REPL • Defragger • Mazes • Memory Leaks • PRNG • Garbage Collecting • Queues • Simple Web Server • Sorting Huge Files • Duplicates • Questions about Software Architecture • No Cache • Event-Driven Architecture • Readability • Emergent and Evolutionary • Scale-Out, Scale-Up • Failures User Sessions • CQRS • n-tier • Scalability • C10K • P2P • CGI • Vendor Lock-in • Pub/Sub • CPUs • Performance • DDOS • Performance and Scalability • Tight Coupling • Cloud Readiness • Emergent Architecture • Design, Architecture, Functionality, Aesthetic • Questions about Service Oriented Architecture and Microservices • Long-lived Transactions • SOA and Micro Services • Versioning and Breaking Changes • Sagas and compensations • Too Micro • Micro Services Architecture • Questions about Security • Security by Default • Don't Invent Cryptography • 2-FA • Confidential Data in Logs • SQL Injection • Detect SQL Injection • XSS • Cross-Site Forgery Attack • HTTPS • MITM Attack • Stealing Sessions • General Questions • Why FP? • Browsers • TCP Sockets • Encapsulation • Real-time systems • Real-time and memory allocation • Immutability • Mutable vs Immutable • Object-Relational Impedance Mismatch • Sizing a Cache • TCP and HTTP • Client-Side vs Server-Side • Reliable and non-reliable channels • Open Questions • Resistance to Change • Threading ELI5 • Innovation and Predictability • Good Code • Streaming • 1 Week Improvement • Learnt this week • Aesthetic • Last 5 books • Introducing CI/CD • Reinvent the Wheel • Not Invented Here • Next Thing to Automate • Coding is Hard • Green Fields and Brown Fields • Type "Google.com" • While idle • Unicode • Defending Monoliths • Professional Developers • It's an art • People…