If you’re an active scroller of Crypto Twitter, it’s easy to become numb to announcements of performance upgrades. Another thousand transactions per second (TPS), another fractional-cent reduction in fees, and whatnot, always. However, this zkSync Atlas upgrade is not a mere speed upgrade only; it is a fundamental re-architecting of the L2 and L3 vision of ZK Stack.
This upgrade is a combination of a new high-performance sequencer, which is capable of 15,000+ TPS, an upgraded prover called Airbender from the earlier Boojom one, that achieves one-second ZK finality, and a new operating system – ZKsync OS.
The true narrative of Atlas is the one it enables: “Incorruptible Finance.” Atlas is designed to change the whole Ethereum L2 ecosystem from a fragmented archipelago of isolated chains now into a single, cohesive “networked economy” of sovereign, interoperable systems. It’s a vision that has earned praise from Ethereum’s founder, Vitalik Buterin himself, who quoted ZKsync founder and said:
This article explores the Atlas upgrade, its technical components, why its architecture is a benefit for L2/L3 chains, and why we think Atlas is a critical catalyst for bringing institutions and enterprises on-chain, at scale.
The Old ZK Stack and the Problem of Isolated Chains
To understand why Atlas is so significant, we must first understand the problem it solves. The future of a ‘world on-chain’ will not be a single, monolithic mega-chain. The diverse needs of finance, gaming, social media, and private enterprises definitely need specialized, sovereign chains.
The ZK Stack was designed for this and it allowed anyone to deploy their own ZK-powered L2/L3 Elastic chains. However, the pre-Atlas architecture shared a necessary evil with the broader L2 ecosystem which is liquidity fragmentation.
Currently, every L2, be it ZK Era, Arbitrum One, or Base, is forced to become its own central liquidity hub. Each chain was effectively a parallel island, and competing to attract its own pool of assets and users. This created massive inefficiencies:
- First, a new L2/L3 had to spend millions on incentives to attract developers and liquidity, often drawing temporary mercenaries rather than sustainable ecosystems.
- Then, moving assets between these islands required trust-based bridges, which are slow, cumbersome, and has significant security risk and point of failure.
- Third, the most important is, this model was antithetical to Ethereum’s vision of composable finance. L2s became parasitic with time. They were draining liquidity from L1 rather than extending it. Interop was slow, especially with optimistic rollups, where a 7-day finality window made L1-L2 interactions painfully slow for institutional use cases.
The pre-Atlas zkStack, is definitely pioneering in the ZK technology, but, was still bound by these limitations. Its sequencer was reliable but modest at ~400 TPS, and its earlier proof system, Boojum, was fast but not real-time.
A new architecture was needed to break out of this limitation and make the L2 and even the ZK narrative hot again. And after the Atlas announcement, ZK is already number 3 in narrative trend this week:
What is the ZKsync Atlas Upgrade?
Atlas is a holistic upgrade of the ZK Stack’s core architecture. It brings three fundamental components together into one next-generation system:
1. zkSync OS:
In previous versions, the virtual machine (VM) was a core, inflexible part of the chain. The Atlas upgrade introduced zkSync OS, which is an operating system layer that sits below the VM.
This OS is designed to be extensible, which means it can host multiple execution environments. This first release ships with a fully equivalent, native EVM environment that allows Ethereum contracts and tools to work without changes. Future versions could run other VMs like WASM or even native RISC-V programs.
Atlas compiles a single system-level state transition program to two targets: x86 for execution inside the sequencer and RISC-V for proving inside the zkVM. That “one program, two targets” removes the earlier “prove a different thing than you execute” risk and shrinks the audit surface.
2.The Atlas Sequencer:
The new Atlas sequencer was rebuilt with one goal: do one job and do it incredibly fast. That job is ordering and executing transactions.
It achieves its massive performance by stripping away all other responsibilities. It does not handle batching, proving, or posting data to Ethereum. Those tasks are handled by separate, asynchronous components. This separation turned the sequencer from a “large committee” into a “dedicated CPU core.”
The results from testing are really impressive:
- ~15,000 TPS on stablecoin transfers with ~500 ms inclusion.
- ~23,000 TPS on high-frequency price updates for oracles.
- ~43,000 TPS on native ETH transfers.
This performance comes with ultra-low latency, with transaction inclusion times between 250-500ms throughout that can give user a real web2 feel.
3.The Airbender Prover:
This is arguably the most consequential part of the upgrade. Airbender is the world’s fastest open-source RISC-V zkVM. Because the zkSync OS compiles all execution to RISC-V, Airbender can prove the entire system.
This new model, “what you execute is what you prove,” is a massive security and simplicity gain. It eliminates the systemic risk of older designs, which required implementing the VM twice—once in Rust for execution and again as cryptographic circuits for proving.
Airbender’s performance is a breakthrough in terms of speed, cost, and efficiency. It can prove an entire block of transactions in ~1 second. The proving cost for a single transfer is approximately $0.0001. And it’s so efficient that a single modern GPU like 4090 can sustain over 1 million transactions per day.
The implication is one-second ZK finality at the network edge and Ethereum finality within minutes.
So, rightly as Nomad said, that tight loop is what makes composability feel monolithic in UX, but it is modular in design.
A Technical Explanation of How the Whole Atlas Upgrade Works Together:
To understand the architecture, let’s trace a single transaction from its source to achieving finality and see how all the above mentioned components work together.
- When a user submits a transfer or function call to a ZK Stack chain, the high-performance Atlas Sequencer includes it in a block within a few hundred milliseconds. This state transition is executed as a Rust program, compiled to the x86 instruction set for the sequencer’s high-speed operation.
- Almost immediately, the trust engine, which is the prover, becomes operative. The Airbender prover takes the very same Rust program, but this time compiled to the RISC-V instruction set, and generates a succinct ZK proof in about one second. This proof is a cryptographic attestation that confirms the state transition for this entire block is correct.
- This proof is then sent to the ZKsync Gateway, which is the network’s central coordination layer. The Gateway verifies proofs from all connected ZK chains (Both public and permissioned) and routes cross-chain messages.
This is where the so-called island model is broken. Imagine a receiving chain (Chain 5) getting a message from this transaction’s chain (Chain 2). Chain 5 does not need to re-execute Chain 2’s logic. It doesn’t need to trust a third-party bridge. It simply verifies the succinct, one-second-old ZK proof from the Gateway.
If Chain 2 is a private Prividium (a private ZK chain), its transaction data remains completely opaque. Only the mathematical proof of correctness crosses the Gateway. This allows a private enterprise chain to interact with public liquidity without leaking a single byte of confidential data.
Want to Build a ZKsync Prividium Chain? Zeeve launched the first-ever Public ZK Prividium for Memento x Deutsche Bank. Read the Case Study
- This architecture completely changes the concept of attaining finality. Because new proofs arrive from every chain every second, the L2-to-L2 interaction achieves what we call one-second ZK finality. And, because the Gateway settles these verified proofs to Ethereum frequently, the L1-to-L2 interaction latency drops below Ethereum’s own block finality time. This gives a seamless user experience where bridging and chain types don’t become a boundary.
This immediately addresses a common institutional concern: atomicity. Cross-chain interactions were a blocker because they lack the synchronous, same-block atomicity of a monolith. In practice, most business flows don’t require this. The one-second proof finality enables a ‘crisp back-and-forth’ that is more than sufficient. For cases that truly demand it (like programmatic bridging or certain arbitrage, Flashloans), atomicity can be achieved with state locks.
The traditional bridges never provided true atomicity. They only simulated it by introducing massive trust and liquidity assumptions. The Atlas architecture, by contrast, grants verifiability. And for an institution, mathematical verifiability is infinitely more valuable than a trusted simulation.
So, there is a lot in terms of architectural simplification. Before Atlas, the EraVM logic was expressed in Rust for execution and then re-expressed as cryptographic circuits for the Boojum prover. This created two separate systems to build, audit, and maintain. With Atlas, the zkSync OS is a single Rust program compiled to two targets: x86 for execution and RISC-V for proving. This is the “what you execute is what you prove” system we mentioned in the previous section. With fewer moving parts, the risk of implementation drift is reduced, and the entire system becomes significantly simpler to audit and secure.
The Benefits of ZKsync Atlas Upgrade to All Layer2 & Layer3 ZK Chains
This new architecture fundamentally changes the L2/L3 value proposition. Here is how:
- The first benefit is visceral: latency. With transaction inclusion in a hundred milliseconds, the lag that was there on most on-chain interactions is simply gone. A checkout flow, a wallet action, or maybe a trade on an order book, all these UX feel like any normal modern web application. This visceral speed is achieved without compromising the core premise of incorruptible finance. Every block is still mathematically proven, not merely attested by governance.
- The second is composability without bridges. Because messages arrive as proofs, you do not depend on third-party bridge liquidity, whitelisted token lists, or brittle off-chain settlement choreography. You wire chains together at the protocol layer. So they are no longer liquidity islands competing with the base layer. They have now become extensions of Ethereum’s settlement and liquidity that share trust via proofs.
- The third is direct access to Ethereum liquidity, and this changes the script on the entire L2 economic model. Earlier rollup generations, especially optimistic stacks with 7-day windows, basically forced ecosystems to recreate a central liquidity hub (Base, Arbitrum One, Era) because round-tripping to L1 was too slow for practical capital movement. Atlas’s one-second ZK finality plus frequent L1 settlement change this. Now, Ethereum has become the capital hub. L2s can source and return liquidity in near real time. The cold-start problem for new chains changes shape. Instead of paying massive integration fees and mercenary incentives to rebuild the same DeFi stack locally, an L2 can simply compose with L1 on day one.
Lighter, currently the 2nd most popular perp Dex, is a great example of this thesis. Lighter’s designers say being an L1 is a bug because it isolates you from Ethereum’s security and capital.
Their architecture is designed based on provable fairness, ZK proofs for matching, and L1 assets are treated as native collateral via universal cross-margin. The point isn’t that every chain should copy Lighter; it’s that to win, we need to leverage Ethereum and not compete with it. Atlas operationalizes that play for any app-chain or sector chain: pull depth from L1, move value across L2s in ~1s, settle quickly, and keep verifiability end-to-end.
- The fourth benefit is multi-VM headroom. By proving the general-purpose RISC-V instruction set, the ZK Stack becomes VM-agnostic. Chains can launch today with perfect, bytecode-level EVM equivalence and instantly access all existing developer tools and protocols. But they are not locked in. As their domains evolve, they can adopt different execution environments, like WASM for high-performance computing or custom runtimes for privacy-preserving finance.
Why Atlas could benefit institutions and enterprises the most
Institutions need two things simultaneously: sovereignty and connectivity.
They must operate systems they control (like access gates, retention policies, privacy defaults, jurisdictional routing, etc) and they must interact with external venues and partners on settlement-grade timelines. Atlas is the first mainstream stack to make this pairing natural rather than tortured.
Take ZKsync Prividium, for example. These private chains have the highest order of sovereignty, with data locality and strict permissions, and every state transition still emits a proof that the network can rely on. Connectivity is just one-second ZK finality at the edge (To the gateway) and minutes-to-Ethereum for L1 reconciliation, which is the horizon that legal and risk teams actually underwrite.
Your counterparty no longer has to trust your logs or your relayer; they verify a succinct proof. Your auditors no longer have to chase dual implementations; they check that what you executed is what you proved. Your CFO no longer has to budget for seven days of settlement drag or for incentive programs to bootstrap copy-paste liquidity. Your CISO likes that the prover can be self-hosted on in-house GPUs for private chains where data must remain on-prem.
This is the inflection point. This is incorruptible finance. It’s exactly why the CT grabbed onto that Vitalik tweet: ‘Incorruptibility is Ethereum’s most important property.’
And it perfectly tees up Haseeb, the managing partner of Dragonfly, saying:
When you see this, and you look at Ethereum’s own march towards single-slot finality, that old 7-day optimistic window looks too old to accept.
That’s the rollup-centric endgame we were promised: L2s like these are the execution layer, and Ethereum is the one and only settlement and liquidity hub.
Launching Your ZK-Stack-Powered Chain with Zeeve Rollups-as-a-Service
For teams that buy the Atlas architecture but don’t want to hand-assemble and manage everything, managed infrastructure is the fastest route from testnet to pilot to production. Zeeve Rollups-as-a-Service is purpose-built for this. Build an Atlas-era ZK chain with observability, SLAs, and 24/7 operations, and then tailor privacy modes, whitelists, data retention, and integration add-ons to your stack without any overhead.
If you’re ready, we can map your domain requirements into an Atlas-ready chain design and translate them into a Zeeve deployment plan. And because all Atlas components are already live on the ZKsync OS Developer Preview testnet, you can start testing workflows now and get ready for mainnet.
