Still on Vue 2? Here’s Why Vue 3 Is Worth It

This Article compares Vue 2 and Vue 3 with an emphasis on the best parts of Vue 3 and the practical reasons to migrate.

Executive summary (why migrate)

• Performance and bundle size: Vue 3 is generally faster and can be smaller due to a redesigned runtime + tree-shaking.
• Modern architecture: The Composition API enables better code organization, reuse, and scaling for large apps.
• TypeScript-first: Vue 3 has much stronger TypeScript support, improving refactors and reducing runtime bugs.
• New platform features: Fragments, Teleport, Suspense (and improved async patterns) unlock cleaner UI patterns.
• Ecosystem direction: The Vue ecosystem is now centered on Vue 3 (most new tooling, examples, and patterns target it).

High-level comparison

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The best parts of Vue 3 (what you “gain”)

1) Composition API (scaling and maintainability)

Why it’s better

• Lets you organize code by feature, not by option buckets (data/methods/computed).
• Encourages reusable logic via composables (cleaner than many Vue 2 mixin patterns).
• Plays exceptionally well with TypeScript (typed refs, typed returns, safer refactors).

What it fixes from Vue 2

• Large components in Vue 2 can become hard to maintain as logic is spread across options.
• Mixins can cause naming collisions and unclear data origins; composables are explicit.

2) Stronger TypeScript + IDE experience

• Vue 3’s core types and patterns are designed around TS.
• Better editor inference improves:
• Refactoring safety
• Autocomplete quality
• Prop/emit correctness

Result: fewer runtime surprises and faster iteration on large codebases.

3) Better performance + smaller bundles (often)

Vue 3 introduced internal changes that typically improve:

• Initial render
• Update/render cycles
• Tree-shaking (dropping unused features from production bundles)

This matters most for:

• large enterprise UIs
• heavy tables/grids
• complex conditional UIs
• apps with strict performance budgets

4) New platform capabilities (cleaner UI architecture)

• Fragments: components can return multiple roots without wrapper divs.
• Teleport: render modals/overlays to body (or other nodes) without hacks.
• Suspense: coordinate async dependencies and fallback UI more cleanly.

These reduce boilerplate and make UI patterns more predictable.

5) Cleaner app/global configuration model

Vue 3’s createApp() changes make global state/config more explicit and less “magical”:

• Less risk of unintended global side effects
• Easier to run multiple Vue apps on one page (when needed)
• Clearer plugin installation and configuration boundaries

Why teams should migrate (business + engineering reasons)

• Lower long-term maintenance cost: Composition API + TS reduces complexity and regression risk.
• Better hiring/onboarding: most new Vue learning materials and patterns are Vue 3-first.
• Ecosystem alignment: modern libraries, tooling, and examples increasingly assume Vue 3.
• Future-proofing: avoiding “stuck on legacy” constraints (tooling drift, harder upgrades later).

Migration reality check (what usually drives effort)

Even when the UI looks the same, migrations typically involve:

• App bootstrap + global API changes (new Vue → createApp, global filters, etc.)
• Third-party library compatibility (UI kits, grids, validation libs)
• Code patterns removed/changed (certain instance methods, legacy patterns)

Most teams succeed by migrating incrementally (see below).

Recommended migration approach (practical and low-risk)

• Start with dependencies: identify which libraries already support Vue 3.
• Upgrade the framework first: move to Vue 3 while keeping behavior stable.
• Adopt Composition API selectively: don’t rewrite everything; migrate high-churn / complex areas first.
• Use incremental verification: component-by-component smoke checks, then deeper regression tests on critical flows.

Hope you liked it. Happy migration.