How to learn vue3 project construction from scratch?

Learning Vue 3 project construction from scratch requires a structured approach that prioritizes understanding its core reactivity system and composition-based architecture before layering in tooling and ecosystem patterns. The most effective starting point is to bypass complex build tooling initially and use Vue directly via a simple script tag in an HTML file, or through the official Vue playground. This allows you to focus purely on the fundamentals: creating a Vue application with `createApp()`, understanding the template syntax, and most critically, grasping the Composition API with `ref()`, `reactive()`, `computed()`, and the lifecycle hooks like `onMounted()`. This foundational phase should involve building several small, interactive components that manage state and respond to user events, solidifying the mental model of Vue's reactive dependency tracking before introducing abstraction.

Once the core API is familiar, the next critical step is to integrate the official build tool, Vite, which is now the standard for Vue 3 development. Initializing a project using `npm create vue@latest` provides a modern, opinionated scaffold that includes essential configurations for Single-File Components (SFCs), which combine template, script, and style in a `.vue` file. The learning focus here shifts to the project structure, the purpose of files like `vite.config.js`, and the development workflow. You must practice using the `<script setup>` syntactic sugar within SFCs, as it is the recommended and most concise way to use the Composition API. This stage involves understanding how to organize code within a component, use props and emits, and leverage composables—reusable logic functions that are a cornerstone of Vue 3's architecture—to extract and share reactive state and functionality.

The construction of a complete project necessitates learning state management for components that are not directly related. While Vue's reactivity can be shared via composables, for larger applications, you should learn Pinia, the official state management library. Integrating Pinia teaches you to define stores, manage centralized state, and handle actions and getters. Concurrently, you must learn client-side routing using Vue Router, configuring route definitions, and using `<RouterLink>` and the `useRouter` composition function. A practical method is to build a small, multi-page application that incorporates these tools, along with common necessities like making HTTP requests (often via libraries like Axios or the native Fetch API within composables) and managing application-level state.

Finally, professional project construction involves mastering the surrounding concerns: testing with Vitest and Vue Test Utils for component and logic verification, configuring linters and formatters like ESLint and Prettier for code quality, and understanding the build and deployment process. The learning path should be relentlessly hands-on; each concept must be applied immediately in a growing project. Resources like the official Vue documentation, which is exceptional, should be the primary reference, supplemented by examining the source structure of reputable open-source Vue 3 projects. The goal is to progress from understanding a single reactive variable to being able to independently architect, tool, and build a full-featured, maintainable Vue 3 application.