The Object-Centric Paradigm in Sui

1. Why Objects?

Traditional blockchains like Bitcoin and Ethereum represent data as balances stored in accounts or UTXOs. While effective, this model creates limitations in scalability, programmability, and usability.

Sui flips the model by treating everything as an object. In this system:

Each object is a standalone data structure.

Objects can be owned by an address, shared by multiple users, or immutable.

Objects can evolve (state changes) through transactions.

This paradigm mirrors how developers already model entities in software, making it more natural to build real-world applications.

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2. Types of Objects

Sui defines three main categories of objects:

1. Owned Objects: Belong to a specific address. Example: an NFT in a user’s wallet.

2. Shared Objects: Accessible by multiple users simultaneously. Example: liquidity pools in DeFi.

3. Immutable Objects: Permanent data that cannot change. Example: metadata for a game item.

This distinction enables Sui to optimize execution paths. For instance, owned objects can be transferred quickly without consensus, while shared objects require stronger coordination.

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3. How Objects Change State

Transactions in Sui describe transformations of objects rather than global balance changes. Example:

A player uses a sword in a game (the sword is an object).

The sword’s durability decreases.

The transaction updates the sword object’s state.

By focusing on objects, Sui allows localized execution — the transaction only touches the relevant object, avoiding unnecessary global bottlenecks.

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4. Benefits for Developers

Clarity: Developers model entities directly (NFTs, weapons, tickets) instead of abstract balances.

Safety: The Move language enforces strict ownership and borrowing rules, reducing bugs.

Efficiency: Transactions only lock affected objects, enabling parallelism.

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5. Example Walkthrough

Imagine a marketplace where Alice lists an NFT for sale:

The NFT is an owned object.

The listing creates a shared object (market entry).

Once Bob buys it, ownership of the NFT object transfers instantly.

Each step involves clear object interactions without needing to reprocess unrelated parts of the chain.

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6. Implications for Applications

NFT Marketplaces: Easy to track individual NFTs with full state history.

Gaming: Weapons, characters, and items become objects with evolving states.

Finance: Tokens can be structured as objects with custom properties (e.g., expiry dates).

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7. Conclusion

The object-centric model is the foundation of Sui’s scalability and usability. It aligns blockchain data with real-world mental models, paving the way for intuitive, high-performance dApps.