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Me_ safwan_07
Me_ safwan_07

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My Personal Experience Managing Local Changes in Database with @ungap/structured-clone

#webdev #programming #javascript #npm

so I was recently working on a web app and hit a classic development headache:

How do I make changes to a local copy of my database data without messing up the original?

Whether you're working with forms, dashboards, or temporary updates - this problem always sneaks in.

That's when I discovered a small but powerful package:
👉 @ungap/structured-clone

It instantly made my workflow cleaner, safer, and a lot less buggy. Here's how.

The Problem: Local Changes, Global Mess

here was my scenario:

  • I fetched a complex object form MongoDB.
  • I wanted to update some values locally - maybe a field like status or title.
  • But I didn't want to mutate the original data until the changes were confirmed or submitted.

Spred Operator or Object.assign()? Not Enough.
I tried the usual tricks:

const copy = { ...originalData };
// or
const copy - Object.assign({}, originalData);
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These only perform shallow copies - they don't help if your object has nested fiedls, arrays, or objects inside.
One small update in the nested data, and - the original object gets affected too.

What Is @ungap/structured-clone?

It's a tiny NPM package - a polyfill for the modern structuredClone() Web API.
(which isn't available in all Node.js versions yet.)

It supports deep cloning of:

  • Objects
  • Arrays
  • Maps & sets
  • Dates
  • Nested values (yep, even deeply nested structures)

Basically, it's like hitting "Duplicate Everything Safely for any JavaScript value".

How I Used It

Installation 

npm install @ungap/structured-clone
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Usage in My Project 

import structuredClone from '@ungap/structured-clone';

const originalData = await getDataFromDatabase();
const localCopy = structuredClone(originalData);

// Make safe local changes
localCopy.status = "Published";
localCopy.updatedAt = new Date();

// Save only after confirming
await saveToDatabase(localCopy);
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Simple. Safe. And it just works.

Why I Loved It

Here are the main benefits I experienced:

  • No accidental mutations
  • Peace of mind while editing deeply nested structures.
  • Great for form editing, draft saving, or statement management

When Should You Use This?

If you're building apps with:

  • Form editing with temporary state
  • Undo/redo functionlity
  • Draft and review workflows
  • Any app where users change data before saving

This tiny tool can save you from unexpected bugs and data inconsistencies.

Bonus: It Plays Well with React

if you're into the React or MERN stack world like me, using structured cloning for local state updates (especially in context or reducers) can be a life-saver.

Final Thoughts

sometimes it's the smallest packages that solve the biggest frustrations.

@ungap/structured-clone gave me the confidence to work with data safely, even in the most complex workflows.

If you're sill manually deep-cloning with weird hacks or libraries, give this a short - I promise you won't regret it.

NPM Link

👉 @ungap/structured-clone

Have you used structuredClone before? Or faced any horror stories with accidental data mutations?

Let’s chat in the comments 👇

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