The Hardest Component I’ve Built in Vue 3 + TypeScript: Dynamic Form Engine

Let’s be honest — building components in Vue can be fun. But once you step into the world of dynamic forms, deeply nested data, reactive state syncing, and validation… it’s no longer fun. It’s war 😅

Here’s a real production challenge I faced while building a dynamic form engine for a high-traffic app using Vue 3, TypeScript, and Pinia.

The Problem

We needed a flexible system where:

• The entire form is built dynamically from a JSON schema.

• It supports nested groups, repeatable sections, and conditional fields.

• Each field has its own validation rules.

• The form autosaves changes to the server via debounce.

• It uses Pinia for state management and full TypeScript typing.

• The form can be paused, resumed, validated, or even branched out conditionally.

The Challenges

1. Deep Reactivity Hell

Nested structures like form.sections[2].fields[5].value are a reactivity nightmare. I had to use toRefs, shallowReactive, and custom utilities to keep Vue from breaking under pressure.

2. Dynamic Component Rendering

One <DynamicField /> had to render an input, select, date, checkbox, or even another <DynamicGroup /> — all based on schema.

3. TypeScript Typing with Schema

The schema had to be parsed into types, and then fields had to be validated against those types. Not fun.

4. Server Syncing

Every change had to be autosaved via API, but without flooding the server. Debounced, cancelable, and retryable logic was built-in.

5. Validation

I used a combo of Zod and custom logic to handle client-side validation + mirror it on the backend.

6. Step-based Navigation

The form was a wizard: multi-step, with caching between steps, conditional paths, and progress logic.

What I Learned

• Vue 3’s Composition API is an absolute weapon — but you have to tame it.

• Deep reactivity needs careful planning — not everything should be reactive.

• TypeScript is your friend, until you start parsing dynamic types… then it becomes your puzzle buddy.

• Building for scale means decoupling UI from logic, and keeping state clean.

Final Thought

This dynamic form engine took weeks to architect, refine, and stabilize.

It’s the hardest thing I’ve built in Vue 3 — and the one I’m most proud of.

If you’ve ever tried building a dynamic form system:

I see you. I feel your pain. I salute you 💪