The SDE path / 2026 edition

Stop guessing what to learn. Start building.

A complete SDE roadmap to help you learn programming foundations, master DSA, build real projects, practice LLD and HLD system design, and prepare for the interviews and engineering work ahead.

00 / overview

01The map

Start herethen

Foundations

Build the habits and technical vocabulary that make everything else easier.

Estimated time4-6 weeks

Write, run, and explain your own programs.

Programming fundamentals
Git, Linux + the web
SQL and basic projects

What to learn and do

Programming fundamentals

Variables, types, control flow, functions, modules, errors, and object-oriented basics.

Complete: Build a small CLI app with input validation and tests.

Git, Linux + the web

Use the terminal, Git branches, pull requests, HTTP, JSON, and browser requests.

Complete: Publish a project to GitHub with a useful README.

SQL and basic projects

Model tables, write CRUD queries, use joins, and connect an app to a database.

Complete: Ship a CRUD project with a clear data model.

Stage checklist

Choose one primary language and learn its core syntax.
Build two small command-line or web projects.
Understand HTTP, databases, and how code runs in production.

12 weeksthen

Problem solving ->

Learn the patterns behind efficient solutions instead of collecting disconnected answers.

Estimated time10-12 weeks

Approach unfamiliar problems with a repeatable method.

Data structures
Algorithms + complexity
Timed practice

What to learn and do

Data structures

Choose arrays, hash maps, stacks, queues, trees, and graphs based on the problem.

Complete: Implement the core structures once without copying code.

Algorithms + complexity

Recognize sorting, searching, recursion, greedy, backtracking, and dynamic programming patterns.

Complete: Explain time and space complexity before coding each solution.

Timed practice

Clarify requirements, communicate trade-offs, test edge cases, and recover from a wrong approach.

Complete: Finish two timed mixed sets and review every miss.

Stage checklist

Learn one pattern at a time, then solve representative problems.
Keep an error log and revisit missed problems every week.
Finish with mixed sets and timed interview practice.

Always onthen

Build things

Turn knowledge into proof. Projects give your ideas constraints, edges, and a user.

Estimated time6-8 weeks

Ship projects you can discuss with confidence.

APIs and databases
Testing + debugging
Portfolio projects

What to learn and do

APIs and databases

Design endpoints, validation, authentication basics, schemas, indexes, and migrations.

Complete: Build and document an API another developer can use.

Testing + debugging

Write unit and integration tests, read logs, reproduce bugs, and use a debugger.

Complete: Add tests for the happy path, failures, and one regression bug.

Portfolio projects

Scope a real user problem, make trade-offs, deploy the result, and measure what matters.

Complete: Publish one polished project with a technical case study.

Project ideas

StarterHabit tracker

Build CRUD flows, streak calculations, filters, and a simple dashboard.

IntermediateIssue tracker API

Add authentication, roles, comments, search, pagination, and tests.

PortfolioLearning platform

Create courses, progress tracking, notes, reminders, and a deployed case study.

Stage checklist

Plan a project around a real user or workflow.
Design the API, data model, and error states before coding.
Deploy it and write a short technical case study.

8-10 weeksthen

Design systems

Move from solving one problem to designing code and services that can change.

Estimated time8-10 weeks

Make thoughtful trade-offs at class and service level.

LLD + design patterns
Scalable architecture
Reliability basics

What to learn and do

LLD + design patterns

Model responsibilities with interfaces, composition, SOLID principles, and useful patterns.

Complete: Design and explain a parking lot or notification system.

Scalable architecture

Break systems into services and reason about traffic, storage, caching, queues, and consistency.

Complete: Draw and defend a URL shortener architecture.

Reliability basics

Plan timeouts, retries, idempotency, observability, backups, and graceful failure.

Complete: Write down failure scenarios and recovery plans for your design.

Stage checklist

Practice modeling requirements as objects, interfaces, and boundaries.
Learn caching, queues, storage, and service communication.
Explain trade-offs with capacity estimates and failure scenarios.

Your next move

Grow your career

Prepare to communicate your work, navigate interviews, and keep improving on the job.

Estimated time3-5 weeks

Show up as an engineer, not just a problem solver.

Resume + storytelling
Mock interviews
Team and career skills

What to learn and do

Resume + storytelling

Describe ownership, decisions, impact, and lessons with concise project stories.

Complete: Create a one-page resume and three project stories.

Mock interviews

Practice coding, design, and behavioral interviews with clear communication under pressure.

Complete: Complete four mocks and record the feedback patterns.

Team and career skills

Give updates, review code, ask for feedback, estimate work, and choose your next learning goal.

Complete: Write a 90-day growth plan tied to a target role.

Stage checklist

Turn your projects into clear stories about decisions and impact.
Run technical and behavioral mock interviews every week.
Create an application loop and keep improving from feedback.

02Choose your starting point

Start at the level that feels like you.

You do not need to begin at the beginning. Choose a level, get a focused starting plan, and move through the roadmap at your pace.

Beginner levelYou are starting from the basics

Start with Foundations

You are learning your first language or still feel unsure about how software is built.

Your first focus

Programming fundamentals
Git, Linux + the web
Small projects and SQL

Begin with foundations ->