Courses

25 developer courses · 809 lessons. Free preview lessons are open to everyone below — no sign-in needed to try them.

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Java25 (LTS)

The language of enterprise back ends. Syntax, OOP, collections, and modern features.

2 free preview · 42 lessons

Spring Boot4.1

Build production-ready Java web apps and REST APIs fast, with almost no boilerplate.

2 free preview · 34 lessons

Maven3.9

The build tool that manages dependencies, compiles, tests, and packages Java projects.

2 free preview · 25 lessons

PostgreSQL18

A powerful open-source relational database. SQL, tables, joins, and more.

2 free preview · 37 lessons

MongoDB8.0

A flexible NoSQL document database. Collections, documents, queries, and aggregation.

2 free preview · 29 lessons

Docker29

Package any app into a container that runs the same everywhere. Images, Dockerfiles, Compose.

2 free preview · 28 lessons

React.js19.2

Build interactive user interfaces with components, props, state, and hooks.

2 free preview · 36 lessons

Angular22

Google's full framework for large web apps. Components, DI, routing, signals, and forms.

2 free preview · 30 lessons

Next.js16.2

The React framework for production. App Router, rendering, caching, Server Actions, and a full API reference.

2 free preview · 72 lessons

Node.js24 (LTS)

Run JavaScript on the server. Modules, npm, async, the file system, and HTTP.

2 free preview · 29 lessons

Express.js5.2

The minimal, popular Node.js web framework. Routing, middleware, and REST APIs.

2 free preview · 28 lessons

NestJS11.1

A structured, TypeScript-first Node.js framework. Modules, controllers, providers, and DI.

2 free preview · 32 lessons

TypeScript6.0

JavaScript with static types. Types, generics, and the advanced type system used across React, Node, Angular, and Nest.

2 free preview · 32 lessons

Git & GitHub2.55

Version control done right. Commits, branching, remotes, pull requests, rebasing, and team workflows.

2 free preview · 30 lessons

JavaScriptES2026

The language of the web. Core syntax, closures, prototypes, the event loop, async, and modern ES features.

2 free preview · 38 lessons

HTML & CSS

The foundation of every web page. Structure with HTML, style with CSS, flexbox, grid, and responsive design.

2 free preview · 32 lessons

Kubernetes1.36

Orchestrate containers at scale. Pods, deployments, services, config, scaling, Helm, and RBAC.

🔒 Premium · 32 lessons

CI/CD

Automate build, test, and deploy. GitHub Actions, pipelines, deployment strategies, and best practices.

🔒 Premium · 24 lessons

Linux & Shell

The command line every backend and DevOps role runs on. Files, permissions, processes, and Bash scripting.

2 free preview · 29 lessons

Cloud

Deploy and scale on AWS, Azure, or GCP. Compute, storage, networking, IAM, serverless, and IaC.

🔒 Premium · 28 lessons

Redis8.8

The in-memory data store for caching, sessions, rate limiting, queues, and real-time features.

2 free preview · 28 lessons

GraphQLSept 2025 Edition

A query language for APIs. Schemas, queries, mutations, resolvers, Apollo, and federation.

2 free preview · 27 lessons

System Design

Design scalable, reliable systems. Scaling, caching, databases, microservices, and real-world tradeoffs.

🔒 Premium · 31 lessons

Web Security

Protect applications from real attacks. OWASP Top 10, auth, XSS, CSRF, SQLi, and secure defenses.

🔒 Premium · 28 lessons

Testing & TDD

Write software that works and stays working. Unit, integration, and e2e tests, mocking, and TDD.

2 free preview · 28 lessons