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12Directions 17Learning paths 155materials

Directions

Twelve directions, from UX/UI to AI. Inside — subsections by technology, from basics to practice.

UX/UI & Product Design

Research, audits, Figma, prototypes, design systems, grids, typography, accessibility and motion.

0 / 18 · materials

Programming Fundamentals

Variables, conditions, functions, data structures, algorithms, OOP, Git, the terminal, HTTP and debugging.

0 / 15 · materials

Frontend Development

HTML, CSS, JavaScript, TypeScript, React, Next.js, Vue, Tailwind, forms, state, testing and performance.

0 / 18 · materials

Backend Development

Node.js, Express, NestJS, Java and Spring Boot, Python, FastAPI and Django, authentication, permissions, jobs.

0 / 13 · materials

Mobile Development

React Native and Expo, Flutter and Dart, Kotlin and SwiftUI, navigation, device APIs, push and publishing.

0 / 12 · materials

Databases

SQL, PostgreSQL, MySQL, Redis and NoSQL, design, indexes, transactions, ORMs and migrations.

0 / 12 · materials

DevOps, Testing & Security

Linux, Docker, Nginx, deployment, CI/CD, monitoring, the testing pyramid, OWASP and secrets.

0 / 12 · materials

Software Architecture

SOLID, patterns, clean architecture, monoliths and microservices, events, APIs, caching and multi-tenant SaaS.

0 / 10 · materials

APIs & Integrations

REST and GraphQL, webhooks, OAuth and OpenID Connect, payments, Telegram, CRM, 1C and reliable external APIs.

0 / 10 · materials

AI Development

LLM APIs, prompting, AI coding assistants, embeddings, RAG, tool calling, agents, evaluation and security.

0 / 16 · materials

Ready-Made Solutions

Code recipes for specific tasks: components, utilities, Next.js, Spring, mobile, auth and SQL.

0 / 11 · materials

Developer Reference

Glossary, Git commands, HTTP codes, CSS, React hooks, SQL, common errors and technology comparisons.

0 / 8 · materials

Learning paths

Ready-made routes: steps go from fundamentals to a practical result.

UX/UI design: from research to a design system

Understand users, structure a screen, build components in Figma and grow them into a design system and a working dashboard.

9 steps

Start

Motion and animation

Why interfaces move, how to pick easing and duration, animate scrolling and transitions between screens.

4 steps

Start

JavaScript from scratch

From a first program to the DOM, error handling and async code, with practice at every step.

9 steps

Start

Markup and layout: HTML and CSS

Semantic markup, Flexbox and Grid layout, responsiveness, Tailwind, performance and accessibility.

7 steps

Start

React

TypeScript, components, state, effects, forms, state management and tests, finishing with an accessible modal.

8 steps

Start

Next.js

App Router, Server Components and Server Actions, Tailwind and performance, plus two ready solutions: a lead form and protected pages.

7 steps

Start

Java

Java syntax, collections and Maven, then OOP, SOLID and patterns, and on to a first REST API on Spring Boot.

6 steps

Start

Spring Boot

HTTP, Java for backend, a Spring Boot REST API, layering, API design, access control and a unified error format.

7 steps

Start

Backend with Node.js

Node.js, a REST API on Express, layering, authentication, permissions, tests and safe password storage.

8 steps

Start

React Native + Expo

Choosing an approach, a first Expo app, navigation, APIs and storage, a ready-made list, device features, push and publishing.

9 steps

Start

Flutter + Dart

Dart and a first Flutter app, state and navigation, a validated form, testing and publishing.

6 steps

Start

SQL and PostgreSQL

Tables and keys, SELECT and JOIN, PostgreSQL in Docker, schema design, indexes, transactions, EXPLAIN and keyset pagination.

9 steps

Start

Docker and deployment

Terminal and Linux, Docker and Compose, secrets, Nginx, choosing a deployment approach and CI with GitHub Actions.

8 steps

Start

Software architecture

Architectural decisions, SOLID and patterns, clean architecture, APIs, monoliths vs microservices, events and system design.

9 steps

Start

APIs and integrations

How APIs work, HTTP, API design, webhooks, resilient external calls, security, payments and an integration adapter.

8 steps

Start

AI integrations

How LLMs work, a first API call, prompting, tool calling, embeddings and RAG, security and quality evaluation.

8 steps

Start

Vibe coding: from prototype to product

How to take an app built with an AI assistant to a real product: Git and rollback, review, data access, tests, boundaries and migrations, release and handover.

7 steps

Start

All materials

Search titles, topics and technologies. Press “/” to jump to search.

01UX vs UI: what’s the difference and why a product needs bothUX Fundamentals · Fundamentals · Beginner · 7 min read

01UX research: finding out what users need without a big budgetUX Research · Fundamentals · Beginner · 10 min read

01UX audit: a step-by-step review of a user flowUX Audit · How-to · Intermediate · 9 min read · practice ~1–2 h

01Visual hierarchy, grids and spacing: how an interface guides the eyeLayout & Grid · Fundamentals · Beginner · 7 min read

01Typography and colour in interfaces: readability, contrast, accessibilityTypography & Color · Fundamentals · Beginner · 6 min read

01Anatomy of a UI component: button, input, card and their statesUI Components · Fundamentals · Beginner · 11 min read

01Figma from scratch: frames, Auto Layout and componentsFigma · Tutorial · Beginner · 14 min read · practice ~1.5–3 h

01Prototyping: from sketch to clickable prototypePrototyping · How-to · Beginner · 10 min read · practice ~30–60 min

01A design system in practice: tokens, components, rulesDesign Systems · Tutorial · Intermediate · 10 min read · practice ~1.5–3 h

01Loading, empty, error: the interface states everyone forgetsUX Patterns · How-to · Intermediate · 6 min read · practice ~30–60 min

01Painless forms: design decisions that bring in more leadsUX Patterns · How-to · Intermediate · 6 min read · practice ~30–60 min

01Designing a dashboard: from user questions to the screenUX Patterns · Tutorial · Intermediate · 11 min read · practice ~1.5–3 h

01Responsive design: how a website adapts to phonesResponsive Design · Fundamentals · Beginner · 6 min read

01Interface accessibility: WCAG for designers and product managersAccessibility · Fundamentals · Intermediate · 8 min read

01Microinteractions and motion: where they help and where they hurtMotion Design · Fundamentals · Beginner · 6 min read

01Easing and duration: why one animation feels premium and another feels cheapMotion Design · Deep dive · Intermediate · 8 min read

01Scroll animations: revealing blocks, parallax and video driven by scrollingMotion Design · Deep dive · Intermediate · 9 min read

01Transitions between screens and states: how motion explains where you've landedMotion Design · Deep dive · Intermediate · 10 min read

02How a website works: frontend, backend and database in plain wordsWeb Basics · Fundamentals · Beginner · 7 min read

02Your first JavaScript program: how code turns into actionProgramming Basics · Tutorial · Beginner · 9 min read · practice ~45–90 min

02Variables and data typesVariables & Data Types · Fundamentals · Beginner · 7 min read

02Conditions and loopsConditions & Loops · Tutorial · Beginner · 7 min read · practice ~45–90 min

02Functions: parameters, return values, scopeFunctions · Tutorial · Beginner · 6 min read · practice ~45–90 min

02Arrays, objects, Map and Set: data structures in practiceData Structures · Fundamentals · Beginner · 8 min read

02Algorithms and complexity: Big O without fearAlgorithms · Fundamentals · Intermediate · 7 min read

02OOP: classes, encapsulation, inheritance and compositionObject-Oriented Programming · Fundamentals · Intermediate · 7 min read

02Terminal and command line for developersTerminal & CLI · Tutorial · Beginner · 10 min read · practice ~45–90 min

02Git from scratch: commits, branches, mergingGit & GitHub · Tutorial · Beginner · 8 min read · practice ~45–90 min

02GitHub: fork, pull request and code reviewGit & GitHub · How-to · Beginner · 9 min read · practice ~30–60 min

02HTTP and JSON: requests, responses, headers and data formatHTTP & JSON · Fundamentals · Beginner · 9 min read

02What is an API in plain words and why a business needs oneAPI Fundamentals · Fundamentals · Beginner · 7 min read

02Debugging: breakpoints, console and reading a stack traceDebugging · How-to · Beginner · 7 min read · practice ~30–60 min

02Error handling: try/catch, async errors and clear messagesError Handling · Fundamentals · Intermediate · 7 min read

03HTML: semantic markup that browsers, search engines and screen readers understandHTML · Fundamentals · Beginner · 12 min read

03CSS layout: Flexbox and Grid on real blocksCSS · Tutorial · Beginner · 9 min read · practice ~45–90 min

03JavaScript in the browser: the DOM and eventsJavaScript · Tutorial · Beginner · 8 min read · practice ~45–90 min

03Asynchronous JavaScript: promises, async/await and fetchJavaScript · Tutorial · Intermediate · 8 min read · practice ~1.5–3 h

03TypeScript from scratch: types, interfaces, genericsTypeScript · Tutorial · Beginner · 11 min read · practice ~45–90 min

03React: components, JSX and propsReact · Tutorial · Beginner · 9 min read · practice ~45–90 min

03React: state and useStateReact Hooks · Tutorial · Beginner · 9 min read · practice ~45–90 min

03useEffect: synchronising with the outside world, and when you don't need itReact Hooks · Deep dive · Intermediate · 9 min read

03Next.js App Router: pages, layouts and routesNext.js · Tutorial · Intermediate · 11 min read · practice ~1.5–3 h

03Next.js: Server Components, data fetching and Server ActionsNext.js · Tutorial · Intermediate · 12 min read · practice ~3–6 h

03Tailwind CSS: utilities, responsiveness and themingTailwind CSS · Tutorial · Beginner · 11 min read · practice ~45–90 min

03Forms and validation in ReactForms & Validation · How-to · Intermediate · 10 min read · practice ~1–2 h

03State management: local, Context, Zustand and server stateState Management · Comparison · Intermediate · 7 min read

03Vue 3 from scratch: components and reactivityVue · Tutorial · Beginner · 7 min read · practice ~45–90 min

03Frontend testing: Vitest and Testing LibraryFrontend Testing · Tutorial · Intermediate · 10 min read · practice ~1.5–3 h

03Accessibility in code: semantics, focus, ARIAWeb Accessibility · How-to · Intermediate · 9 min read · practice ~1–2 h

03Site speed and Core Web Vitals: what to measure and how to speed upWeb Performance · Fundamentals · Intermediate · 6 min read

03Frontend architecture: project structure, layers and boundariesFrontend Architecture · Deep dive · Advanced · 9 min read

04What backend is: server, API, database and everything in betweenBackend Fundamentals · Fundamentals · Beginner · 10 min read

04Node.js from scratch: modules, npm and a first serverNode.js · Tutorial · Beginner · 9 min read · practice ~45–90 min

04REST API on Express: CRUD, validation, errorsExpress · Tutorial · Beginner · 9 min read · practice ~1.5–3 h

04NestJS: modules, controllers, services and DTOsNestJS · Tutorial · Intermediate · 11 min read · practice ~1.5–3 h

04Java for backend: syntax, types, collections and MavenJava · Tutorial · Beginner · 10 min read · practice ~1.5–3 h

04Spring Boot: a REST API from scratchSpring Boot · Tutorial · Intermediate · 8 min read · practice ~3–6 h

04FastAPI: a Python API with validation and documentationFastAPI · Tutorial · Beginner · 11 min read · practice ~1.5–3 h

04Django: models, admin and viewsDjango · Tutorial · Beginner · 10 min read · practice ~1.5–3 h

04Authentication: sessions, cookies and JWTAuthentication · Deep dive · Intermediate · 14 min read

04Authorization: roles, permissions and server-side access checksAuthorization · How-to · Intermediate · 8 min read · practice ~1–2 h

04Background jobs and queues: what to move out of the requestBackground Jobs · How-to · Intermediate · 10 min read · practice ~1–2 h

04Backend testing: unit and integration tests for an APIBackend Testing · Tutorial · Intermediate · 8 min read · practice ~1.5–3 h

04Backend application layers: controller, service, repositoryBackend Architecture · Fundamentals · Intermediate · 10 min read

05Mobile development: native, React Native or FlutterMobile Fundamentals · Comparison · Beginner · 9 min read

05React Native and Expo: your first appReact Native & Expo · Tutorial · Beginner · 9 min read · practice ~1.5–3 h

05Navigation in Expo Router: stacks, tabs, parametersMobile Navigation · Tutorial · Intermediate · 9 min read · practice ~1.5–3 h

05React Native: API requests and local storageState Management · Tutorial · Intermediate · 8 min read · practice ~1.5–3 h

05Flutter and Dart: your first appFlutter & Dart · Tutorial · Beginner · 9 min read · practice ~1.5–3 h

05Flutter: state and navigationFlutter · Tutorial · Intermediate · 8 min read · practice ~1.5–3 h

05Android with Kotlin and Jetpack Compose: your first screenKotlin & Android · Tutorial · Beginner · 11 min read · practice ~1.5–3 h

05iOS with SwiftUI: your first screenSwift & SwiftUI · Tutorial · Beginner · 10 min read · practice ~1.5–3 h

05Camera, location and permissions: device APIsDevice APIs · How-to · Intermediate · 7 min read · practice ~1–2 h

05Push notifications: how they work and how to connect themPush Notifications · How-to · Intermediate · 7 min read · practice ~2–4 h

05Testing mobile appsMobile Testing · Fundamentals · Intermediate · 9 min read

05Publishing to the App Store and Google PlayApp Publishing · How-to · Intermediate · 11 min read · practice ~1–2 h

06Databases: tables, keys and why a business needs themDatabase Fundamentals · Fundamentals · Beginner · 10 min read

06SQL from scratch: SELECT, WHERE, ORDER BYSQL · Tutorial · Beginner · 9 min read · practice ~45–90 min

06SQL: JOIN, GROUP BY and aggregatesSQL · Tutorial · Beginner · 10 min read · practice ~45–90 min

06PostgreSQL: running in Docker, psql and a first tablePostgreSQL · Tutorial · Beginner · 11 min read · practice ~45–90 min

06Database design: relationships, keys and normalisationDatabase Design · Tutorial · Intermediate · 10 min read · practice ~1.5–3 h

06Indexes: speeding up queries without slowing down writesIndexes · Deep dive · Intermediate · 9 min read

06Transactions and isolation: ACID without the mysteryTransactions · Deep dive · Intermediate · 8 min read

06ORM and migrations with PrismaORM & Migrations · Tutorial · Intermediate · 13 min read · practice ~1.5–3 h

06Query optimisation: EXPLAIN ANALYZE in practiceQuery Optimization · How-to · Advanced · 9 min read · practice ~2–4 h

06Redis: cache, TTL and countersRedis · Tutorial · Intermediate · 11 min read · practice ~1.5–3 h

06NoSQL: documents, key-value, and when they beat SQLNoSQL Concepts · Comparison · Intermediate · 9 min read

06PostgreSQL or MySQL: practical differencesMySQL · Comparison · Intermediate · 8 min read

07Linux for developers: files, permissions, processes, SSHLinux · Tutorial · Beginner · 12 min read · practice ~45–90 min

07Docker from scratch: image, container, DockerfileDocker · Tutorial · Beginner · 9 min read · practice ~45–90 min

07Docker Compose: app and database locally with one commandDocker · Tutorial · Intermediate · 7 min read · practice ~1.5–3 h

07Nginx as a reverse proxy: HTTPS, static files, headersNginx · How-to · Intermediate · 9 min read · practice ~1–2 h

07Domain, hosting, DNS and SSL: what they are and what must belong to youHosting · Fundamentals · Beginner · 6 min read

07Deployment: VPS, PaaS or containers, and zero-downtime releasesDeployment · Comparison · Intermediate · 10 min read

07CI/CD with GitHub Actions: checks on every pull requestCI/CD · Tutorial · Intermediate · 14 min read · practice ~1.5–3 h

07Monitoring and logging: what to collect and how to reactMonitoring & Logging · Fundamentals · Intermediate · 14 min read

07The testing pyramid: unit, integration, e2eTesting · Fundamentals · Intermediate · 13 min read

07E2E tests with PlaywrightE2E Testing · Tutorial · Intermediate · 13 min read · practice ~1.5–3 h

07OWASP Top 10 for developersApplication Security · Fundamentals · Intermediate · 13 min read

07Secrets and environment variables: how not to leak your keysSecrets Management · How-to · Intermediate · 11 min read · practice ~30–60 min

08Software architecture: what it is and which decisions belong to itArchitecture Fundamentals · Fundamentals · Intermediate · 11 min read

08SOLID with clear examplesSOLID · Fundamentals · Intermediate · 9 min read

08Design patterns you actually needDesign Patterns · Fundamentals · Intermediate · 9 min read

08Clean architecture: dependencies point inward, module boundariesClean Architecture · Deep dive · Advanced · 12 min read

08Modular monolith or microservicesModular Monolith & Microservices · Comparison · Advanced · 12 min read

08Event-driven architecture and message queuesEvent-Driven & Message Queues · Deep dive · Advanced · 14 min read

08API design: resources, versioning, errors, paginationAPI Design · How-to · Intermediate · 17 min read · practice ~1–2 h

08Caching and invalidationCaching · Deep dive · Advanced · 13 min read

08Multi-tenant SaaS: isolating tenant dataMulti-Tenant SaaS · Deep dive · Advanced · 14 min read

08System design by example: a booking service and scaling itSystem Design · Tutorial · Advanced · 17 min read · practice ~3–6 h

09REST or GraphQLREST & GraphQL · Comparison · Intermediate · 14 min read

09GraphQL: schema, queries and mutationsGraphQL · Tutorial · Intermediate · 11 min read · practice ~1.5–3 h

09Webhooks: receiving, signatures, retries and idempotencyWebhooks · How-to · Intermediate · 12 min read · practice ~1–2 h

09OAuth 2.0 and OpenID Connect: signing in with another accountOAuth 2.0 & OpenID Connect · Deep dive · Intermediate · 12 min read

09Payment integration: flow, statuses and webhooksPayment Integrations · How-to · Intermediate · 12 min read · practice ~2–4 h

09Telegram bot: Bot API, commands and a webhookTelegram Bots · Tutorial · Beginner · 8 min read · practice ~1.5–3 h

09CRM integration: adapter, field mapping, synchronisationCRM Integrations · How-to · Intermediate · 12 min read · practice ~1–2 h

091C for developers: HTTP services and OData1C Integrations · How-to · Intermediate · 12 min read · practice ~1–2 h

09External APIs: timeouts, retries, rate limits and graceful degradationExternal APIs & Error Handling · How-to · Intermediate · 12 min read · practice ~1–2 h

09Integration security: keys, signatures, least privilegeIntegration Security · Fundamentals · Intermediate · 11 min read

10LLMs: how language models work and what they can doAI Fundamentals · Fundamentals · Beginner · 9 min read

10LLM APIs: a first request to Claude and OpenAILLM APIs · Tutorial · Beginner · 7 min read · practice ~1.5–3 h

10Prompt engineering: instructions, examples, output structurePrompt Engineering · How-to · Beginner · 7 min read · practice ~30–60 min

10AI assistants in development: Claude Code and Codex in practiceAI-Assisted Coding · How-to · Intermediate · 11 min read · practice ~30–60 min

10Embeddings and vector search with pgvectorEmbeddings & Vector Databases · Tutorial · Intermediate · 11 min read · practice ~1.5–3 h

10RAG: answers grounded in your documentsRAG · Tutorial · Intermediate · 11 min read · practice ~3–6 h

10Tool calling: the model calls your functionsTool Calling · Tutorial · Intermediate · 11 min read · practice ~1.5–3 h

10AI agents: the loop, tools, boundaries and automationAI Agents & Automation · Deep dive · Advanced · 11 min read

10Evaluating LLM features: test sets and metricsAI Evaluation · How-to · Advanced · 15 min read · practice ~1–2 h

10LLM application security: prompt injection and data leaksAI Security · Fundamentals · Intermediate · 12 min read

11Recipe: an accessible modal dialog in ReactReact Components · Code recipe · Intermediate · 8 min read · practice ~40–90 min

11Recipe: debounce and throttleJavaScript Utilities · Code recipe · Beginner · 6 min read · practice ~20–40 min

11Recipe: a lead form on a Server Action with validationNext.js Solutions · Code recipe · Intermediate · 8 min read · practice ~40–90 min

11Recipe: protected pages in Next.jsNext.js Solutions · Code recipe · Intermediate · 8 min read · practice ~40–90 min

11Recipe: a unified error format in Spring BootJava / Spring Recipes · Code recipe · Intermediate · 7 min read · practice ~20–40 min

11Recipe: a list loaded from an API with pull-to-refresh in React NativeReact Native Recipes · Code recipe · Intermediate · 7 min read · practice ~20–40 min

11Recipe: a form with validation in FlutterFlutter Components · Code recipe · Intermediate · 7 min read · practice ~20–40 min

11Recipe: storing passwords — hashing and verificationAuthentication Recipes · Code recipe · Intermediate · 9 min read · practice ~20–40 min

11Recipe: a typed API client on fetchAPI Recipes · Code recipe · Intermediate · 7 min read · practice ~20–40 min

11Recipe: keyset pagination in SQLDatabase Recipes · Code recipe · Intermediate · 8 min read · practice ~20–40 min

11Recipe: a port and an adapter for an external serviceReusable Architecture Patterns · Code recipe · Advanced · 7 min read · practice ~40–90 min

12Website section names: hero, header, CTA and other termsUX/UI Glossary · Reference · Beginner · 7 min read

12Git command referenceGit Command Reference · Reference · Beginner · 10 min read

12HTTP status codes: a referenceHTTP Status Codes · Reference · Beginner · 8 min read

12CSS reference: selectors, units, Flexbox and GridCSS Reference · Reference · Beginner · 9 min read

12React hooks referenceReact Hooks Reference · Reference · Intermediate · 7 min read

12SQL reference: queries, data changes, DDL and transactionsSQL Reference · Reference · Beginner · 11 min read

12Common JavaScript, React and Next.js errors and how to fix themCommon Errors · Troubleshooting · Beginner · 14 min read

12Technology comparison: what to choose for a website, an app and a backendTechnology Comparisons · Comparison · Intermediate · 13 min read

10Git in AI-assisted development: small steps, branches and rolling back an agentVibe Coding · Tutorial · Beginner · 11 min read · practice ~1.5–3 h

10Reviewing AI-written code: what to look at firstVibe Coding · How-to · Intermediate · 8 min read · practice ~1–2 h

10Data access in an AI-built MVP: roles, client-side keys and RLSVibe Coding · Tutorial · Intermediate · 8 min read · practice ~3–6 h

10Tests for generated code: pin down behaviour before you change itVibe Coding · Tutorial · Intermediate · 8 min read · practice ~1.5–3 h

10Architecture boundaries and migrations in an AI project: rules for the agentVibe Coding · How-to · Intermediate · 9 min read · practice ~1–2 h

10Releasing and handing over an AI-built MVP: what to prepareVibe Coding · How-to · Intermediate · 8 min read · practice ~1–2 h

143 terms

Glossary of terms

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Message on WhatsApp

A library for developers and designers.

Directions

UX/UI & Product Design

Programming Fundamentals

Frontend Development

Backend Development

Mobile Development

Databases

DevOps, Testing & Security

Software Architecture

APIs & Integrations

AI Development

Ready-Made Solutions

Developer Reference

Learning paths

UX/UI design: from research to a design system

Motion and animation

JavaScript from scratch

Markup and layout: HTML and CSS

React

Next.js

Java

Spring Boot

Backend with Node.js

React Native + Expo

Flutter + Dart

SQL and PostgreSQL

Docker and deployment

Software architecture

APIs and integrations

AI integrations

Vibe coding: from prototype to product

All materials

Glossary of terms

Got a project?We'll scope and estimate it — for free.

Got a project?
We'll scope and estimate it — for free.