Frontend
ReactReact: getting started
AngularAngular: getting started
VueVue: getting started
TypeScriptTypeScript Essentials
Backend
PythonPython: getting started, FastAPI: a Python backend
Node.jsHTTP and REST APIs, Node.js: getting started, Express: an API server, Auth and security
DatabasesSQL and PostgreSQL, Prisma ORM, Databases: going deeper
GraphQLGraphQL: getting started
DevOpsDocker and deployment, Docker basics, Kubernetes: the basics, CI/CD with GitHub Actions
ArchitectureSystem Design
SecurityWeb application security
Basics
GitGit: getting started
FoundationsHTML Essentials, CSS: getting started, SCSS: getting started, JavaScript Essentials
Computer ScienceAlgorithms and Data Structures, Programming principles
TestingTesting: unit, integration, e2e
New
TodayYour lesson plan for today
Docker basicsImage, container, volume
CI/CD with GitHub ActionsWorkflow, job, deploy
Kubernetes: the basicsPod, Deployment, Service
Testing: unit, integration, e2eVitest, Playwright
Cheat sheetsEach course syntax on one page
Start with a demo lessonEvery course has a free demo lesson. Pick a stack and try it in 10 minutes.Pick a course
All courses
Frontend
JavaScriptClosures, this, event loop, promises
TypeScriptTypes, generics, narrowing
ReactRendering, hooks, state and effects
Frontend performanceCore Web Vitals, bundles, rendering
Backend
Node.jsEvent loop, streams, modules
HTTPMethods, status codes, caching, CORS
SQLJoins, indexes, transactions
DatabasesData models, replication, sharding
Engineering
GitBranches, merge, rebase
AlgorithmsComplexity, data structures, problems
System designScaling, caching, queues
DevOpsDocker, CI/CD, deploys
Web securityXSS, CSRF, authentication
TestingUnit, integration, e2e
Practice
Question practiceAnswer and review on a schedule
All questionsQuestions with answers by topic
Practice questionsShort daily reviews so the answers stick until the interview.Start practice
All interview topics
Categories
Programming languages
Frontend
Backend
Mobile
Databases
Caching and search
Messaging and streaming
DevOps
Cloud
Serverless
Auth
Observability
Testing
Comparisons
React vs Angular vs VueFrontend frameworks
TypeScript vs JavaScriptDo you need types
PostgreSQL vs MySQLRelational databases
Kafka vs RabbitMQQueues and streaming
Kubernetes vs DockerContainers and orchestration
Architecture
All patternsFrom monoliths to queues and caches
Monolith, microservices or serverlessWhat to pick for your project
MicroservicesWhen to split a system into services
CachingWhere to cache and how to invalidate
Message queueAsync work between services
Compare technologiesPros, cons and when to pick which, in one table.Open the comparison
Whole knowledge base
CV
CV guideStructure, experience and common mistakes
CV templatesReady templates for your level
ATS systemsHow a CV gets past automated screening
Cover lettersA short letter that gets read
Job search
LinkedInA profile recruiters find
Job sitesWhere to look for IT jobs
Freelance platformsWhere to land your first gig
Job search seriesTools, step by step
Communities
Ukrainian IT communitiesWhere to find your people
Global communitiesInternational developer communities
Telegram channelsJobs and news in your feed
YouTube channels69 channels worth watching
IT mythsWhat is true about getting into IT
CV templatesPick a template for your level and fill it in one evening.Open templates
All career guides
Forum
Questions and answersAsk and help others
Ask a questionDescribe the problem, the community will help
RulesHow we talk here
Mentors
Find a mentorCode, CV and career reviews
Become a mentorShare your experience with newcomers
Find a mentorExperienced developers help with code and career.Choose a mentor
Whole community
Pricing

My learning
Path
Frontend
ReactReact: getting started
AngularAngular: getting started
VueVue: getting started
TypeScriptTypeScript Essentials
Backend
PythonPython: getting started, FastAPI: a Python backend
Node.jsHTTP and REST APIs, Node.js: getting started, Express: an API server, Auth and security
DatabasesSQL and PostgreSQL, Prisma ORM, Databases: going deeper
GraphQLGraphQL: getting started
DevOpsDocker and deployment, Docker basics, Kubernetes: the basics, CI/CD with GitHub Actions
ArchitectureSystem Design
SecurityWeb application security
Basics
GitGit: getting started
FoundationsHTML Essentials, CSS: getting started, SCSS: getting started, JavaScript Essentials
Computer ScienceAlgorithms and Data Structures, Programming principles
TestingTesting: unit, integration, e2e
New
TodayYour lesson plan for today
Docker basicsImage, container, volume
CI/CD with GitHub ActionsWorkflow, job, deploy
Kubernetes: the basicsPod, Deployment, Service
Testing: unit, integration, e2eVitest, Playwright
Cheat sheetsEach course syntax on one page
Start with a demo lessonEvery course has a free demo lesson. Pick a stack and try it in 10 minutes.Pick a course
All courses
Frontend
JavaScriptClosures, this, event loop, promises
TypeScriptTypes, generics, narrowing
ReactRendering, hooks, state and effects
Frontend performanceCore Web Vitals, bundles, rendering
Backend
Node.jsEvent loop, streams, modules
HTTPMethods, status codes, caching, CORS
SQLJoins, indexes, transactions
DatabasesData models, replication, sharding
Engineering
GitBranches, merge, rebase
AlgorithmsComplexity, data structures, problems
System designScaling, caching, queues
DevOpsDocker, CI/CD, deploys
Web securityXSS, CSRF, authentication
TestingUnit, integration, e2e
Practice
Question practiceAnswer and review on a schedule
All questionsQuestions with answers by topic
Practice questionsShort daily reviews so the answers stick until the interview.Start practice
All interview topics
Categories
Programming languages
Frontend
Backend
Mobile
Databases
Caching and search
Messaging and streaming
DevOps
Cloud
Serverless
Auth
Observability
Testing
Comparisons
React vs Angular vs VueFrontend frameworks
TypeScript vs JavaScriptDo you need types
PostgreSQL vs MySQLRelational databases
Kafka vs RabbitMQQueues and streaming
Kubernetes vs DockerContainers and orchestration
Architecture
All patternsFrom monoliths to queues and caches
Monolith, microservices or serverlessWhat to pick for your project
MicroservicesWhen to split a system into services
CachingWhere to cache and how to invalidate
Message queueAsync work between services
Compare technologiesPros, cons and when to pick which, in one table.Open the comparison
Whole knowledge base
CV
CV guideStructure, experience and common mistakes
CV templatesReady templates for your level
ATS systemsHow a CV gets past automated screening
Cover lettersA short letter that gets read
Job search
LinkedInA profile recruiters find
Job sitesWhere to look for IT jobs
Freelance platformsWhere to land your first gig
Job search seriesTools, step by step
Communities
Ukrainian IT communitiesWhere to find your people
Global communitiesInternational developer communities
Telegram channelsJobs and news in your feed
YouTube channels69 channels worth watching
IT mythsWhat is true about getting into IT
CV templatesPick a template for your level and fill it in one evening.Open templates
All career guides
Forum
Questions and answersAsk and help others
Ask a questionDescribe the problem, the community will help
RulesHow we talk here
Mentors
Find a mentorCode, CV and career reviews
Become a mentorShare your experience with newcomers
Find a mentorExperienced developers help with code and career.Choose a mentor
Whole community

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