Free Programming & Engineering Courses

Structured courses with explanations, comparison tables and code in several stacks — from REST API design and GraphQL to idempotency, event sourcing, distributed systems, payments and LLM integration.

Engineering Fundamentals

API Architecture and Integration Design REST, GraphQL, gRPC, events and webhooks; contract-first OpenAPI; pagination, errors, idempotency and versioning; gateways, BFFs… API Design · 10 lessons API Platform & Lifecycle Run APIs as products: contract-first OpenAPI 3.1 and AsyncAPI 3, mocks, Spectral governance, breaking-change CI, contract… API Design · 20 lessons API Security in Depth The OWASP API Security Top 10 (2023) in practice: BOLA, BOPLA, BFLA, OAuth 2.1 and RFC 9700, token validation, fine-grained… Web Security & WAF · 20 lessons Authentication & Authorization Architecture Design identity for modern systems: passwords and sessions, OAuth 2.0 and OIDC, tokens, MFA and passkeys, SSO, authorization… Authentication · 10 lessons Caching and Performance Engineering Caching layers, cache patterns and invalidation, HTTP caching and CDNs, Redis, measuring performance, database tuning, scaling… Caching · 10 lessons Database Caching at Scale Caching for high-traffic systems without stale or leaked data: cache-aside done right, the stale-set race, versioned keys, TTLs… Caching · 20 lessons Design Patterns, Explained Simply SOLID and all 23 classic design patterns, plus the patterns modern frameworks are built on, explained in plain language with… Design Patterns · 39 lessons Distributed Systems for Backend Engineers The theory behind modern backends: clocks and ordering, consistency models, CAP/PACELC, replication, partitioning, consensus,… Distributed Systems · 20 lessons DSA Patterns Made Simple The coding-interview patterns that solve most problems, taught one at a time: how to spot each pattern, one short template to… Algorithms & Data Structures · 21 lessons ETL and Data Pipelines Build data pipelines that are correct, re-runnable and cheap to operate, through real production problems: ETL vs ELT, batch vs… Data Engineering · 22 lessons Event Sourcing & CQRS Model domains as events: event modeling, aggregates, event stores, CQRS and projections, eventual consistency in the UI,… Messaging & Queues · 20 lessons GraphQL in Production Design, secure and operate GraphQL APIs: schema design and nullability, mutations and errors, DataLoader and cost limits,… API Design · 20 lessons Idempotency & Retry-Safe Systems Make every operation safe to retry: idempotent design, Idempotency-Key implementation, timeouts and deadlines, backoff with… Reliability · 20 lessons Integrating LLM APIs Ship LLM features like any other production dependency: models and tokens, prompts as code, streaming, structured outputs, tool… AI Integration · 20 lessons Kafka in Production Build and run event-driven systems on Apache Kafka 4: topics, partitions, keys and offsets, reliable producers with acks and… Messaging & Queues · 10 lessons Messaging, Events and Email Systems Queues, streams and background jobs, delivery guarantees, outbox and CDC, event design, sagas, Kafka in practice, notification… Messaging & Queues · 10 lessons Mobile API Best Practices Design backends for iOS and Android: screen-shaped responses, payload and battery efficiency, offline-first and delta sync,… Mobile · 20 lessons Observability and Operations Logs, metrics and traces with OpenTelemetry, SLOs and burn-rate alerting, incident response, runbooks, telemetry pipelines, safe… Logging & Observability · 10 lessons Payments & Money APIs Build correct money systems: representing money, how card payments work, PSP integration models and PCI scope, SCA, payment… Payments · 20 lessons Queues & Background Processing in Depth Messaging models, message design, ordering, acknowledgements, broker choice, job frameworks by stack, retries and DLQs, poison… Messaging & Queues · 20 lessons Rate Limiting, Quotas & Abuse Protection Protect APIs with the right algorithms (windows, token bucket, GCRA), distributed limiters, RateLimit headers, quotas and plans,… Reliability · 20 lessons Real-Time APIs WebSockets, SSE, long polling and WebTransport; designing, receiving and securing webhooks; fan-out, presence, connection… Messaging & Queues · 20 lessons Request Lifecycle: How Web Frameworks Handle a Request Follow a request from the socket to the response in the frameworks you use: the proxy and server chain, PHP-FPM, WSGI, ASGI and… Web Framework Internals · 17 lessons Resilience Patterns Design systems that survive failure: failure modes and metastability, timeout budgets, circuit breakers, bulkheads, load… Reliability · 20 lessons REST APIs in Depth Industry-standard REST API design for any stack: resource modeling, HTTP semantics, status codes, JSON conventions, pagination,… API Design · 20 lessons Scaling Databases & Data Consistency Scale relational databases the way high-traffic products do: find the queries that matter, index for real workloads, fix N+1 and… Databases & Transactions · 20 lessons Software Architecture Foundations Modern architecture practices for scalable systems: event-driven design, microservices, DDD, consistency, and resilience patterns. System Design Problems · 5 lessons System Design Interviews, Step by Step A repeatable method for system design interviews, then worked walkthroughs of the questions asked most: URL shortener, rate… System Design Problems · 14 lessons Testing in Practice Write tests that catch real bugs without slowing teams down: a testing strategy across unit, integration and end-to-end levels,… Testing · 11 lessons Transactions, Locking & Concurrency in Code Real production bugs and their fixes: transaction boundaries, framework pitfalls, long transactions, pool exhaustion, isolation… Databases & Transactions · 20 lessons Web Security and WAF The OWASP Top 10 in practice: injection, XSS and CSP, CSRF and CORS, access control and SSRF, plus TLS and headers, WAFs and… Web Security & WAF · 10 lessons

Engineering Leadership

The Engineering Manager Handbook (Development Manager) A practical course for engineering managers and development managers: the manager operating system, the first 90 days with a new… Engineering Management · 20 lessons The Team Lead Handbook A practical course for team leads: the move from engineer to lead, team charters and working agreements, effective 1:1s,… Team Lead · 20 lessons The Tech Lead Handbook A practical course for new and experienced tech leads: what the role owns, the first 90 days, balancing code and leadership,… Tech Lead · 20 lessons

Programming

Android with Kotlin and Jetpack Compose Build modern Android apps with Kotlin and Jetpack Compose: composable screens, layouts and lists, state and side effects,… Android · 11 lessons ASP.NET Core Web APIs Build ASP.NET Core Web APIs on .NET 10 that hold up in production: minimal APIs with route groups and typed results, built-in… C# · 11 lessons C# Fundamentals: From Your First Program to Async and JSON Learn modern C# on .NET from the first line to real applications: the dotnet CLI, types and string formatting, control flow and… C# Fundamentals · 11 lessons Dart Fundamentals: The Language Behind Flutter Learn modern Dart 3 from the ground up: variables and sound null safety, functions with named parameters, collections with… Dart Fundamentals · 10 lessons Data Analysis with pandas Analyse data with pandas 3: DataFrames and Series, loading messy CSV files with the right types, selecting and filtering,… pandas · 11 lessons Django from Basics to Production Build web apps and APIs with Django 6.1 and Django REST framework: views and URLs, models and the ORM, relationships without N+1… Django · 12 lessons Elixir Fundamentals: Functional Programming and OTP Learn Elixir from the ground up: immutable data, pattern matching, multi-clause functions and pipes, collections and Enum,… Elixir Fundamentals · 10 lessons FastAPI: From Basics to Production Build production-ready Python APIs with FastAPI: Pydantic v2, dependency injection, async SQLAlchemy and Alembic, JWT auth,… FastAPI · 35 lessons Flask API Fundamentals Build lightweight Python APIs with Flask routing, request handling, JSON responses, and blueprints. Flask · 4 lessons Go Programming Fundamentals A hands-on path through Go syntax, tooling, and concurrency, built from the official Go documentation and tour. Backend · 6 lessons Go Web Frameworks: net/http, Chi, Gin, Echo and Fiber Build the same JSON API with the Go standard library and the four most popular Go web frameworks, then learn the parts every… Go Web Frameworks · 12 lessons HTML5 for Beginners: Build Your First Web Pages Start from zero: what the web and HTML are, where HTML came from (from Tim Berners-Lee's 18 tags to HTML5 and today's Living… HTML & CSS · 16 lessons htmx: Build Interactive Web Apps with HTML Build modern, interactive web apps by returning HTML from your server instead of JSON. Start with why hypermedia works,… htmx · 18 lessons iOS with SwiftUI Build modern iPhone and iPad apps with Swift and SwiftUI: views, layout and lists, state with @Observable, NavigationStack,… iOS · 11 lessons Mobile Apps with React Native and Expo Build real iOS and Android apps with React Native, Expo and TypeScript: screens and styling, fast lists, navigation with Expo… React Native · 15 lessons Modern Angular: Signals, Standalone Components and SSR Learn modern Angular (v22) the way new apps are built: standalone components with signal inputs, outputs and model, template… Angular · 10 lessons Modern C++ Fundamentals: From Basics to Smart Pointers and Threads Learn modern C++20 from your first program to safe, fast code: building and formatting, values and references with const… C++ Fundamentals · 11 lessons Modern HTML5 in Production Fix the real-world problems HTML is responsible for: pages screen-reader users can't navigate, controls keyboards can't reach,… HTML & CSS · 15 lessons MongoDB from Basics to Production Learn MongoDB from documents and queries to production: CRUD with update operators, query operators and projections, data… MongoDB · 11 lessons NestJS in Production Build and run NestJS 12 services that stay maintainable: modules and dependency injection, DTO validation, domain errors and… Node.js · 11 lessons Next.js App Router in Production Build and run Next.js 16 App Router applications that are fast, secure and operable: Server and Client Components, dynamic… Next.js · 10 lessons Node.js Backend Fundamentals with Express Build backend APIs with Node.js 24 and Express 5: routes and routers, path and query parameters, middleware, validation with… Node.js · 11 lessons PHP 7: Maintaining and Upgrading Legacy Apps Work confidently in PHP 7 codebases: language features, testing and refactoring legacy code, security hardening, and a safe path… PHP 7 · 35 lessons PHP 8: Modern PHP Development From PHP 8 syntax and types to enums, property hooks, Composer, PDO, security, testing and production deployment with OPcache,… PHP 8 · 37 lessons Python Programming Deep Dive A structured path from Python syntax to practical software habits, based on the official Python tutorial. Python · 6 lessons React: From Components to Production Modern React 19 with TypeScript: components, state and effects, forms and Actions, TanStack Query, React Router, performance and… React Developer · 36 lessons Rust Fundamentals: Ownership, Errors and Fearless Concurrency Learn Rust from your first program to safe parallel code: Cargo, types and control flow, ownership and borrowing, structs and… Rust Fundamentals · 12 lessons Spring Boot: From Basics to Production Build and run Java 21 services with Spring Boot: dependency injection, REST APIs, validation, Spring Data JPA, Spring Security… Java Developer · 35 lessons Tailwind CSS in Production The Tailwind CSS problems real teams hit, each with a live demo and the fix: classes missing from the build, overrides that… HTML & CSS · 12 lessons TypeScript Fundamentals: Types, Generics and Real-World Patterns Learn TypeScript from your first typed program to production patterns: strict mode and inference, objects and interfaces, unions… TypeScript Fundamentals · 11 lessons Vue 3 and Nuxt Learn Vue 3 and Nuxt 4 from the ground up: reactivity with ref, reactive, computed and watch; single-file components with props,… Vue · 11 lessons XML in Production The XML failures that reach production and how to prevent them: namespace changes that silently empty an import, encoding… Data Formats · 12 lessons

Cloud

Cloud Engineering in Production The cloud incidents that actually happen, AWS first with Azure and Google Cloud equivalents: leaked access keys, public buckets,… Cloud Engineering · 11 lessons Cloud Networking in Production The network problems that cause real outages in the cloud: overlapping address ranges, exhausted subnets, NAT port exhaustion,… Cloud Networking · 10 lessons DevOps in Production The DevOps failures that hurt real teams: rollbacks blocked by destructive migrations, secrets left in image layers, floating… DevOps · 11 lessons Docker from Basics to Production Containerize real applications and run them well: production-shaped Dockerfiles for Python and Node.js, a Compose development… Docker · 11 lessons Helm, Kustomize and GitOps with Argo CD Package and deliver Kubernetes applications safely: values schemas that catch typos, template indentation bugs, upgrades blocked… Kubernetes · 12 lessons Java Serverless on AWS Lambda Run production Java on AWS Lambda through real failures: event deserialization, where JVM cold-start time goes, SnapStart… Java Serverless · 14 lessons Kubernetes in Production Run Kubernetes workloads through the failures teams actually hit: errors during deploys, OOMKills and evictions, dropped… Kubernetes · 13 lessons Linux and Bash for Developers The Linux and Bash skills developers need on real servers, taught through the problems you'll actually meet: disks that stay… Linux · 13 lessons Node.js Serverless on AWS Lambda Build and run production Node.js and TypeScript services on AWS Lambda through real production problems: async handlers and cold… Node.js Serverless · 25 lessons Python Serverless on AWS Lambda Run production Python on AWS Lambda through real failures: leaking module state, native wheels that will not load, slow… Python Serverless · 14 lessons Terraform in Production Running Terraform safely with a team: locked remote state on AWS, Azure and GCP, secrets kept out of state, drift detection,… Infrastructure as Code · 11 lessons

AI

AI Agents and MCP in Production Build agents that stay bounded, recover from tool failures and can be debugged: the agent loop and its budgets, tool definitions… Agents · 13 lessons Coding with AI Assistants Use AI coding assistants and agentic coding tools well: what they are good and bad at, giving them project context, asking for… AI-Assisted Development · 12 lessons Forward Deployed Engineering in Practice What goes wrong when software meets real customers, and how forward deployed engineers fix it: messy production data, corporate… Forward Deployed Engineering · 11 lessons LLM Evals and Guardrails Know whether your LLM feature works and keep it safe: eval sets from real traffic, code, model and human graders, LLM-as-judge… Evaluation · 13 lessons Machine Learning Fundamentals for Engineers Practical machine learning with scikit-learn for software engineers: the supervised learning workflow and baselines, regression… scikit-learn · 11 lessons Native AI Engineering: LLMs, RAG & Agents A practical introduction to building applications with large language models, retrieval, and agents, drawing on widely used open… Native AI Engineering · 6 lessons RAG in Production Build retrieval-augmented generation that finds the right text and answers faithfully: structure-aware chunking, hybrid search… RAG · 13 lessons

Other

Career Growth Foundations A practical starter course covering job search planning, learning habits, and career confidence. 6 lessons GitHub Actions: CI/CD Workflows From First Run to Secure Deployments Learn GitHub Actions the practical way: workflows, events and filters, a real CI workflow with caching, build matrices,… GitHub Actions Fundamentals · 10 lessons