Aptos vs. Sui: a detailed comparison

Aptos and Sui are exceptionally fast (over 100,000 tps) and scalable smart contract platforms. Both use the Move language, originally developed for Meta’s Diem project, and count Diem executives among their founders. Let’s see how they compare in terms of technology, performance, available dApps, and more.

What are Aptos and Sui?

Aptos and Sui are both new L1 blockchains, or smart contract platforms. This means that various dApps (DEXes, wallets, games etc.) can be built on top of them, just like on Ethereum, Solana, Avalanche, Fantom, etc.

Both Sui and Aptos use a similar model of the Move programming language, originally developed for Diem. While Aptos has continued to use the original Move language, Sui has deviated to their own version of “Sui Move”. Diem was a blockchain project backed by Meta (Facebook) — first called Libra and later renamed to Diem. Meta did pilot a wallet called Novi but finally sold the project to the Silvergate crypto bank in January 2022.

For all intents and purposes, Diem is dead, but the most valuable assets that were created for it — Move and the virtual machine Move VM — are open-source, so other projects can use them.

Move is a very safe and efficient language that helps developers avoid many of the coding errors that can result in exploits. In turn, Move VM is an alternative to Ethereum Virtual Machine — a secure environment for running smart contracts.

While Diem was supposed to be a permissioned network, Sui and Aptos are decentralized and permissionless: anyone will be able to join them as a validator. They also share the same vision: onboard the first billion blockchain users.

Founders and backers

Aptos

The Aptos blockchain is presented by Aptos Labs, led by two former Diem executives:

• Mo Shaikh — a veteran founder and expert on scaling businesses, he led the strategic partnerships division at Novi (Meta) and even spoke at the World Economic Forum in Davos.

• Avery Ching, CTO — former principal software engineer at Novi and at Facebook and Yahoo before that.

In July 2022, Aptos raised $150 million from investors like FTX Ventures, a16z (Andreessen Horowitz), Jump Crypto, and Multicoin Capital. This follows a $200 million funding round back in March, in which a16z and Multicoin also participated, together with Tiger Capital, Katie Haun, etc.

Interesting factL=: the name ‘Aptos’ comes from the language of the Ohlone Indians and means ‘the people’. The Ohlone live in California, where Aptos is based.

Sui

Sui is created by Mysten Labs, also based in California. The key figures on the team include four former Meta/Novi team members:

Evan Cheng, CEO — former R&D director at Novi and Engineering Director at Facebook before that;

Adeniyi Abiodun, CPO (Chief Product Officer) — previously Product Lead at Novi an Head of Product at Vmware;

Sam Blackshear, CTO — previously Principal Engineer at Novi;

George Danezis, Chief Scientist — a professor of Security and Privacy Engineering at University College London and a former research scientist at Facebook/Novi.

Mysten Labs is backed by Andreessen Horowitz (a16z), Redpoint, Coinbase Ventures, and Electric Capital, among others. In December 2021, it attracted $36 million in a Series A funding round. As of August 2022, the company was trying to raise another $200 million in a Series B round.

Aptos vs. Sui at a glance

Architecture and consensus

AptosBFT: a consensus model based on HotStuff

Consensus is a mechanism that allows blockchain nodes (validators) to come to an agreement on the validity of transactions and blocks. At the core of both Aptos and Sui, there is a consensus concept called BFT, or Byzantine Fault Tolerance. Its main idea is that even if some (up to one third) of the validators go offline or become malicious, the network can still operate normally.

Aptos relies on an advanced version of BFT consensus called HotStuff. It was modified by Diem to produce DiemBFT, and Aptos has further improved on it under the name AptosBFT. We’ve covered it in detail in the recent article on the Aptos consensus, but here’s the gist:

• In HotStuff, there is a leader who suggests a new block, and the rest of the validators vote on it.
• Since all the validators communicate with the leader, the total number of messages sent out in every round is much lower than if the validators also communicated with each other.
• Once everyone agrees that a block is valid, it becomes final — this fast finality is a key advantage of Aptos over blockchains like BNB Chain, where finality takes 30 seconds, or Solana, where it’s around 6 seconds.
• The leader changes with every round of voting, with a new leader selected in a verifiably random way.
• The leader can work on several blocks at the same time (one in the Pre-Commit stage, another in the Commit stage, etc.) — this is called pipelining.

Block-STM: Aptos’ parallel execution engine

Block-STM, where STM stands for ‘Software Transactional Memory’, is a system created by Aptos to process up to 160,000 transactions per second. In layman’s terms, transactions are first executed by the nodes in parallel and only then validated. If there is a problem at this stage, a transaction can be aborted and re-executed or discarded.

Block-STM also determines the dependencies between transactions, so if an operation cannot be validated, those that depend on it will also be re-executed. Finally, once all the conflicts have been resolved, all the transactions in a block are committed to the blockchain together (so-called lazy commit).

Not having to execute all the transactions sequentially or define the dependencies in advance saves a lot of time and resources. It also scales well — thus the idea of Aptos as the most scalable L1 chain.

This chart from Aptos’ Medium blog shows how the maximum TPS depends on the

Sui: getting rid of consensus for simple transactions

Sui takes a radical step, eliminating consensus for many transactions altogether. Simple transfers of tokens by their owner to a different address, without any other transactions depending on them, are confirmed virtually instantly. The sender broadcasts the transaction, collects validators’ votes (handshakes), and receives a so-called certificate of validity.

However, Sui does use a more traditional BFT consensus for more complex transactions that involve so-called shared objects — assets that can be modified by more than one owner (unlike tokens in a wallet). This applies to many interactions with smart contracts.

This approach makes Sui an L1 for specific use cases where a dApp generates huge numbers of simple transactions, needs them to be confirmed with low latency and is less concerned with decentralization. Good examples include games and airdrops.

Like Aptos, Sui also uses parallel execution for simple transactions without dependencies, while complex operations are executed sequentially in precise order.

Narwhal and Tusk

The consensus engine used by Sui has a name: Narwhal and Tusk. It was developed by several researchers at Mysten Labs and Aptos Labs and later open-sourced, so now any blockchain can integrate it (in fact, Celo is already working on it).

Narwhal is the mempool module: it makes sure that transaction data is available. It can also be used on its own (without Tusk) with other consensus engines, such as HotStuff or Cosmos’ Ignite. The architecture of Narwhal is that of a DAG, or a Directed Acyclic Graph: its many elements are linked together as a network rather than a chain (like it happens in a blockchain).

Tusk is the consensus module that orders the transactions submitted for consensus (for complex transactions).

We won’t go into too much technical detail, but you can learn more about Narwhal and Tusk here or here. The important part is that Narwhal and Tusk allow each validator to process more transactions in a unit of time. And if you were wondering about the name, a narwhal is a 15ft-long whale that looks like a unicorn because of its long tusk.

Performance

Aptos: 130,000 TPS and sub-second finality

Both Sui and Aptos blockchains are incredibly powerful, fast and scalable. Aptos can process 130,000 tps (transactions per second): this result was achieved during a speed test. We’ve already discussed Block-STM, which plays a major part in this and can increase this to 160,000 tps, but here’s a recap of the innovations that make such speeds possible:

• parallel transaction execution — if there is a problem with validation, an operation is re-executed together with those that depend on it;
• state sync — a protocol that allows non-validator peers to verify and synchronize data across the blockchain;
• lazy commit: all the operations in a block are committed in bulk;
• collaborative scheduling: transaction execution is scheduled in such a way as to use the resources efficiently.

According to the latest report from the team, the DevNet now achieves up to 4.5k TPS with transaction execution and even 10k TPS when the latest state synchronization techniques are activated. The next benchmark is 100k TPS, though of course, the real performance test will come when Aptos launches the mainnet.

The theoretical maximum capacity is 160,000 transactions per second, but what’s even more important is the sub-second finality. For the end user, it’s not the TPS that’s important but how quickly their transaction is finalized. On Aptos this happens in less than a second, while on Solana, for example, it’s 6 seconds.

Sui: “unlimited” TPS and near-instant finality

Sui’s performance targets are also interesting: the team claims their TPS is potentially “infinite.” As the network load grows, Sui nodes (called authorities) can keep adding workers (a sort of secondary nodes) to create a mini-network and execute more transactions.

In a recent test, a single node running on a Macbook Pro with 8 cores processed 120.000 transactions per second. The result strongly depends on the type of transactions, though: in this test, a user sent tokens to 100 different addresses (accounts) using a single signature. When making transfers one by one to a single recipient every time, the same node could execute only 20,000 TPS. Sui’s horizontal scaling is thanks to its consensus model, where simple transactions don’t require a global consensus (as we explained above).

Also, since no consensus is needed in most cases, finality is sub-second. In this regard, Sui and Aptos have similar time to finality. But for a long time, this probably won’t matter, as it will take the mainnets quite a while to reach such a number of users as to generate thousands of transactions per second. Solana is a good example: it processes over 2000 transactions per second, but up to 90% of those are validator votes, so the real transactions sent by users are only about 200–300.

When will Aptos and Sui blockchain mainnets go live?

Aptos mainnet is planned to launch in autumn of 2022, followed by an additional incentivized testnet.

However, even on DevNet, Aptos is already huge, with a peak of over 20,000 nodes. This makes it one of the largest Proof-of-Stake chains out there in terms of node participation. For comparison, Ethereum’s Beacon Chain has 415,000 nodes, but Solana has fewer than 2,000.

Sui hasn’t announced a mainnet launch date yet. As the incentivized testnet (see below) should start in Q3 (or potentially Q4), the mainnet could theoretically go live by the end of 2022, but will probably depend on the results of the incentivized stage.

What can you get involved with Aptos and Sui right now?

Incentivized testnets

An incentivized testnet is a gamified campaign that onboards validators (users who run nodes) to stress-test the consensus, practice staking, identify bugs, test how upgrades work, and so forth. They are rewarded with tokens and often compete for the top spot on the leaderboard. If you are a developer or have experience as a blockchain validator, joining an incentivized testnet can be a great way to learn more about the exciting Move technology.

Aptos has already completed two out of the four planned stages of its Aptos Incentivized Testnet, or AIT. The 3rd stage is planned for August 30 — September 9, followed by the mainnet launch, and then AIT4 (the fourth stage) in winter.

From Aptos’ meme channel. Credit: @AndriiIzotov

Sui announced its own incentivized testnet in June and opened validator submissions on August 2. Every successful validator will receive 2,000 SUI. Moreover, 10% of the whole SUI emission will be staked with the best-performing participants who go on to become validators on the mainnet.

Weekly AMAs

The best way to stay updated on these exciting new L1 chains is to tune in to their regular AMA (Ask Me Anything) sessions.

Mysten Labs tends to hold thematic AMAs: for example, the latest streams were dedicated to the SUI tokenomics, the Move language, and technical writing. You’ll find the date and time of the next AMA on Sui’s Discord.

The Aptos team holds weekly Move Mondays on Twitch. They are mostly development updates but also open up the meeting to Q&A, and also very much worth watching. See Aptos Discord for details.

To learn even more about what’s happening around the Aptos blockchain, you can tune into our weekly Pontem Network AMAs with the Key Protocol Contributor Alejo Pinto. The discussion usually centers on the Aptos dApp ecosystem, security, building a new DeFi infrastructure, etc. For the link to the next AMA, check our Telegram chat.

Wallets and other dAapps for the Sui and Aptos blockchains

Even though Aptos and Sui are still in the DevNet stage as of August 2022, you can already try out some dApps.

Aptos ecosystem

Wallets

There is already a functional wallet for Aptos, created by our own Pontem Network blockchain studio. It has just been added to the Chrome Web Store, while the users of other browsers can download the wallet extension in .zip from GitHub.

What makes Pontem Wallet truly special is that it can directly integrate various DeFi features. Instead of linking the wallet to a DEX, for example, you’ll be able to swap tokens directly in the wallet. In the near future, we are also considering adding features like liquid staking and DeFi integrations for liquid staking derivatives (think liquidity pools with Anchor’s stETH, but on Aptos).

If you use MetaMask, you’ll find Pontem Wallet very easy to handle. It works on the testnet for now (as there is no mainnet), but you can request free APTOS tokens and send a transaction to another Pontem Wallet address (without spending any real money).

Apart from Pontem Wallet, we should mention two more wallets: Martian and Fewcha. Both are available as Chrome extensions and allow you to receive test tokens from a faucet and send them to other DevNet addresses. In addition, Martian has a nice NFT minting demo, while Fewcha is actively working on a mobile app.

DEX/AMM exchange

The first AMM for the Aptos blockchain was also built by Pontem Network. It’s called Liquidswap and it’s already working on DevNet. You can connect to the DEX using Pontem Wallet and make a few swaps with APTOS, BTC and USDT without any risk.

Development tools

Pontem Network has released two more tools:

• Move Code Playground: an browser-based code editor that lets programmers practice coding for all Move-compatible blockchains. For now it’s just Aptos and Sui, but more chains based on Move may appear in the future, and our Code Playground will be compatible with any of them.
• Move Intellj IDE plugin: a tool for coders who use Intellij IDEs (integrated development environment software) by JetBrains. The plugin makes it possible to experiment with Move and build whole dApps for Aptos in a graphic interface that the developer is used to. It has handy features like on-the-fly error checks, syntax highlighting, and automatic code formatting.

NFTs on Aptos: Topaz marketplace, Aptos Name Service & more

You’ll be surprised to learn that there are already over 20 NFT collections on the Aptos testnet. They are listed on Topaz, the first Aptos NFT marketplace so far. Topaz is integrated with the Martian wallet and even plans to release a launchpad soon.

The most prominent NFT collection is Aptos Names, which is basically domain addresses for the metaverse.

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The idea is to link long crypto addresses and other blockchain assets to human-readable addresses like justsayhello.aptos or readyplayer1.aptos, creating a single identifier for the metaverse. The best-known example is ENS (Ethereum Name Service), but other chains are now getting their own name services.

Other NFT collections on the Aptos blockchain devnet include Topaz Punks and Aptos Punks, Pokemon2, and a version of Azuki, as well as the official collection of the second Aptos NFT marketplace, Souffl3.

Lending and borrowing on Aptos

Vial is the first lending protocol on Aptos. The interest rate is determined algorithmically based on the supply and demand ratio in the pools. You can lend or borrow APTOS, wrapped BTC, or USDC — all on the testnet, or course. The current lending APY is 8%, while it costs 10% (annualized) to borrow. Vial also has a faucet to get free testnet BTC and USDC.

dApps for Sui: the first Sui Wallet

In July, Sui launched its own wallet extension for Chrome, where you can create a Sui address, send testnet tokens and NFTs, or connect to an NFT minting demo dApp. The wallet is meant to show other developers what can be done with Sui, so the team doesn’t expect it to become the ‘official’ wallet of the ecosystem.

As of the time of writing, there are no publicly available AMMs, NFT marketplaces, lending protocols, or other dApps for Sui.

Aptos and Sui tokens: beware of scams

As of August 2022, Aptos and Sui haven’t announced a token yet, and you can’t buy or get their tokens anywhere. The respective tokens should be released once the two chains’ mainnets go live, but for now there is no information about a token sale, allocations, exchanges, etc. Even the participants of the Aptos Incentivized Testnet, who have already earned their rewards, will have to wait for the mainnet launch to receive them.

You can, however, get free test tokens on the testnet if you want to try out the dApps. For example, the new Pontem Wallet for Aptos has a Request Tokens feature in the Address menu. Note that such test tokens don’t have any market value: you can’t sell them or transfer them out of the testnet.

If you see anyone promoting an ‘IDO’ of Aptos or Sui tokens or offering you to buy them on a DEX, remember that this is a scam. Such fake offers are particularly rife on Discord: if you are a member of the Aptos or Sui servers, you’re likely to get a DM from a scammer at some point, perhaps even impersonating someone from the team.