Engineering · Stable

Software Engineer: Skills, Projects & Interview Questions (2026)

Design, build and maintain reliable software across the stack.

Demand 9/102026 outlook 8/10Difficulty 6/10High remote₹9–42 LPA (indicative)

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What a Software Engineer actually does

Designing, coding, reviewing and shipping software across the stack.

Top hiring companies: Google, Amazon, Microsoft, Meta, Atlassian, Flipkart.

Top industries: Tech, Finance, E-commerce, Product Startups, SaaS.

Skills you need to become a Software Engineer

Skill	Importance	Learning hours	Interview weight
Data Structures & Algorithms	10/10	~120h	High
Programming Language (Java/Python/C++)	10/10	~80h	High
Object-Oriented Programming	9/10	~40h	High
Databases (SQL)	9/10	~40h	High
System Design	8/10	~80h	High
Git & Version Control	8/10	~20h	Medium
APIs & REST	8/10	~40h	High
Testing	7/10	~30h	Medium
Operating Systems	7/10	~40h	High
Computer Networks	7/10	~30h	Medium

Core tools: Git, VS Code / IntelliJ, Docker, Postman, PostgreSQL / MySQL, Jira.

Software Engineer learning roadmap

Beginner · 3-4 months

Foundations & core tooling

Build: Solve 50 DSA problems and build a small CRUD app in one language.

Intermediate · 4-5 months

Applied, real-world builds

Build: Build a full CRUD service with a database, REST API and tests.

Advanced · 4-6 months

Production, scale & specialization

Build: Design and build a scalable service with caching, a system-design write-up and CI/CD.

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10 Software Engineer portfolio projects

CLI To-Do App

Beginner

Command-line task manager with storage.

Skills: Programming, Data Structures

CRUD Web App

Beginner

Full CRUD app with a database.

Skills: Programming, Databases, APIs

REST API Service

Intermediate

REST API with auth and tests.

Skills: APIs, Databases, Testing

URL Shortener

Intermediate

Design and build a URL shortener.

Skills: System Design, Databases, APIs

Real-time Chat App

Intermediate

Chat with websockets and storage.

Skills: Programming, APIs, Databases

Algorithm Visualizer

Intermediate

Visualize sorting/graph algorithms.

Skills: Data Structures, Programming

Job Queue System

Intermediate

Background job processing with a queue.

Skills: APIs, Programming, Databases

Scalable Service

Advanced

Service with caching, queues and system-design doc.

Skills: System Design, Caching, APIs

E-commerce Backend

Advanced

Catalog, cart and order service.

Skills: System Design, Databases, APIs

API Rate Limiter

Advanced

Implement a distributed rate limiter.

Skills: System Design, Caching, APIs

Common Software Engineer interview questions

Find if a string has balanced parentheses.Easy

What they're testing: Stack-based matching

Explain *args and **kwargs.Easy

What they're testing: Variadic positional and keyword arguments

Explain horizontal vs vertical scaling.Easy

What they're testing: Add machines vs bigger machine; trade-offs

How do you resolve a merge conflict?Medium

What they're testing: Reconcile overlapping changes, test

REST vs GraphQL.Medium

What they're testing: Fixed endpoints vs flexible queries

How do you troubleshoot a service that won't start?Medium

What they're testing: journalctl, status, logs, config

TCP vs UDP.Easy

What they're testing: Reliable ordered vs fast connectionless

How would you detect a cycle in a linked list?Medium

What they're testing: Floyd's fast/slow pointers

What are decorators? Give an example use.Medium

What they're testing: Wrap a function to add behavior; logging, caching, auth

What is a load balancer and what algorithms exist?Easy

What they're testing: Distribute traffic; round-robin, least-conn, hashing

What is a pull request workflow?Easy

What they're testing: Review and integrate via branches

How do you version and secure an API?Medium

What they're testing: Versioning, auth, rate limiting

Practice the full Software Engineer question bank →

Certifications for Software Engineers

AWS Certified Solutions Architect - AssociateAmazon Web Services · Very High value

Software Engineer career path

SDE -> SDE II -> Senior SDE -> Staff/Principal Engineer

Common moves into this role / from here:

→ AI Engineer (6-9 months) — close: ML fundamentals, statistics, deep learning, LLMs, RAG, vector databases

Related roles: Backend Engineer, Full Stack Developer, Frontend Engineer

Frequently asked questions

What skills do you need to become a Software Engineer?

Core skills include Data Structures & Algorithms, Programming Language (Java/Python/C++), Object-Oriented Programming, Databases (SQL), System Design. Communicate your problem-solving clearly and write clean, tested code.

What projects should a Software Engineer build for a portfolio?

Strong starter projects: CLI To-Do App; CRUD Web App; REST API Service; URL Shortener.

How long does it take to become job-ready as a Software Engineer?

A focused plan runs roughly 3-4 months for fundamentals, then applied projects. Difficulty rating: 6/10.

What is the career path for a Software Engineer?

SDE -> SDE II -> Senior SDE -> Staff/Principal Engineer

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