Taiko's upcoming upgrade, Shasta, is a complete redesign of the core protocol with two objectives:

1. Simplicity

2. Efficiency

After this upgrade, Taiko (and based rollups by design) will be simpler and cheaper than most alternative rollup models. Preliminary benchmarks have shown more than a 20x reduction in gas fees when proposing and an 8x reduction in proving compared to the previous version (Pacaya).

Shasta is also 5x-15x more efficient for proposers than other popular zk rollups.

This upgrade advances Taiko toward Stage 1 and establishes the foundation for permissionless preconfirmations.

Based rollups were proposed with one main purpose in mind: to scale Ethereum while staying true to its values. This means not only inheriting the L1 security, but also its other properties: liveness, censorship resistance, decentralization and credible neutrality. At Taiko, we've adhered to this ethos from the beginning, even when taking shortcuts would have been easier.

The excitement around based sequencing, built at the end of 2024 and beginning of 2025, has vanished, leaving two common criticisms: 

1. Speed: Without preconfirmations, waiting for (at least) an entire L1 slot is too slow for most use cases and user expectations.
   Preconfirmations have already proved to solve this issue. What remains is fully decentralizing them, onboarding L1 validators and reducing block times. But after EIP-7917 went live in Fusaka, this is an implementation problem and a matter of months.

2. Economic feasibility (i.e., they are too expensive): Preconfirmations partially solved the cost issue by reducing the frequency at which proposers need to post to the L1, but the changes introduced in Shasta are the real game-changer. With this new protocol design, based rollups can be cheaper than most zk rollups, and once sharing is achieved, they can be significantly cheaper than most other L2s (under similar levels of activity).

This is why we are excited about the upcoming Shasta upgrade, and we expect it to be one of the turning points that moves our industry from the place it is today, where Taiko is still the only based rollup in production, to a world where abundant adoption comes in, and tens of rollups join the ecosystem.

Shasta is a complete redesign of Taiko's protocol, designed from first principles and informed by the experience of running a rollup in production, as well as our collaboration on the minimal-rollup. We've designed Shasta with three principles in mind:

1. Simplicity: simple protocols are key to innovation. When something is simple to understand, it is also simpler to extend and audit. Shasta removes most of the complexity found in earlier protocol design.

2. Efficiency: Ethereum-grade security and properties do not have to come at a higher cost for users. As it turns out, simplifying the protocol also significantly reduces costs. Shasta achieves a 20x reduction in proposing costs and a 5x reduction in proving and finalization costs.

3. Move complexity off-chain: Advances in zk proving have made proving costs and latency drop dramatically. This has allowed us to move a lot of the protocol checks and complexity to derivation and proving.

How does Shasta work?

The protocol is designed around three main contracts, but we've removed all wrappers, unnecessary abstractions and more:

• Inbox: The inbox is the main rollup contract, representing and enforcing the rollup rules on L1 with two main functions:

  • Propose: Accepts blobs, processes forced inclusions (if they’re due), updates the CoreState and emits an event for provers. That's it, no complex accounting or on-chain checks for protocol-wide rules (e.g. gas limits, timestamps, etc.). All that is derived off-chain and enforced by the prover.
    

  • Prove: Process bonds (if the proof is late), calls the zk verifier, and finalizes the chain by syncing the state of L1 to enable withdrawals and L2->L1 messages. The move to sequential proofs was a key change that unlocked significant simplification and efficiency. This means that proposals are proven (and thus finalized) in order.
    
    This removes the need to have on-chain proof conflict detection and to have a different mechanism to aggregate proofs and finalize the chain.
    

• Anchor: It runs as the first transaction of every L2 block, and its main purpose is to inject the state of the L1 into the L2. This allows deposits and L1->L2 messages, and it will also serve as a commitment store for preconfirmation slashing.
  
  We've removed most other complexities and responsibilities from the anchor.
  

• SignalService: the core mechanism for exchanging messages and bringing tokens between the L1 and Taiko. We've simplified by removing complex structures such as HopProofs, while still keeping it backwards compatible (meaning bridges and intent providers don't need to upgrade).

All of the above sounds great, but what are the actual results?

• Proposing new blocks: Before Shasta, proposing new blocks on Taiko could cost up to 1M gas, and the cost scales with the amount of L2 blocks in that batch (because we were posting metadata about each). This increases the cost of proposer operations, which in turn results in higher fees for users.  Shasta reducesproposals cost ~ 45k gas (once the initial warm-up period has passed, and the proposal ring buffer is full). This means a 22x reduction in proposing fees on mainnet.
  

• Proving new batches: Before Shasta, proving a batch cost ~ 500k gas. With zk proof verification accounting for roughly 250,000 gas, execution alone consumed the remaining 250,000. 

Under Shasta, execution costs drop to around 30,000 gas and remain nearly constant regardless of how many batches are being proven. This strongly favors aggregation, allowing more batches to be verified for roughly the same cost.

This is an 8x reduction in gas costs.

But how do these numbers compare to other rollups?

Each rollup has a slightly different way to run validations, proof systems, and L1 to L2 messaging, which makes direct comparisons difficult. But a good starting point is looking at other zk rollups, which all share a similar flow. Data is posted to L1 (a.k.a propose), you prove the transition (a.k.a prove), and then finalize the chain, posting a checkpoint from L2 to L1, against which messages can be verified. This is the result of querying the 7-day average in Dune and projecting the costs after Shasta.

We've removed a lot of code. And when we say a lot, we mean A LOT.

Removing code sounds easy; you just delete it, right? But true simplicity is not easy. We think people will find the Shasta codebase the simplest rollup contract to read, audit and understand. And that's very powerful.

We're proud to say that Taiko is now one of the easiest rollup protocols to understand, even if you're just getting started.

Security has always been Taiko’s top priority. Shasta has been in development for several months, with careful review and testing of every part of the code. The protocol is already running on internal devnets, where preconfers are testing their software to ensure everything works as expected.

Hoodi will be updated in the coming weeks, giving users early access to the latest improvements. Following final testing on Hoodi, the team plans to submit Shasta as a proposal to the Taiko DAO. Activation on mainnet will depend on successful verification and community approval.

Explore open positions on our job board.

Get the latest from Taiko:

• Website: https://taiko.xyz.

• Discord: https://discord.gg/taikoxyz.

• GitHub: https://github.com/taikoxyz.

• Twitter: https://twitter.com/taikoxyz.

• Community forum: https://community.taiko.xyz.

• YouTube: https://www.youtube.com/@taikoxyz.

• Warpcast: https://warpcast.com/taikoxyz.

Contribute to Taiko on GitHub and earn a GitPOAP! You will also be featured as a contributor on our README. Get started with the contributing manual.

Taiko's upcoming upgrade, Shasta, is a complete redesign of the core protocol with two objectives:

1. Simplicity

2. Efficiency

After this upgrade, Taiko (and based rollups by design) will be simpler and cheaper than most alternative rollup models. Preliminary benchmarks have shown more than a 20x reduction in gas fees when proposing and an 8x reduction in proving compared to the previous version (Pacaya).

Shasta is also 5x-15x more efficient for proposers than other popular zk rollups.

This upgrade advances Taiko toward Stage 1 and establishes the foundation for permissionless preconfirmations.

Based rollups were proposed with one main purpose in mind: to scale Ethereum while staying true to its values. This means not only inheriting the L1 security, but also its other properties: liveness, censorship resistance, decentralization and credible neutrality. At Taiko, we've adhered to this ethos from the beginning, even when taking shortcuts would have been easier.

The excitement around based sequencing, built at the end of 2024 and beginning of 2025, has vanished, leaving two common criticisms: 

1. Speed: Without preconfirmations, waiting for (at least) an entire L1 slot is too slow for most use cases and user expectations.
   Preconfirmations have already proved to solve this issue. What remains is fully decentralizing them, onboarding L1 validators and reducing block times. But after EIP-7917 went live in Fusaka, this is an implementation problem and a matter of months.

2. Economic feasibility (i.e., they are too expensive): Preconfirmations partially solved the cost issue by reducing the frequency at which proposers need to post to the L1, but the changes introduced in Shasta are the real game-changer. With this new protocol design, based rollups can be cheaper than most zk rollups, and once sharing is achieved, they can be significantly cheaper than most other L2s (under similar levels of activity).

This is why we are excited about the upcoming Shasta upgrade, and we expect it to be one of the turning points that moves our industry from the place it is today, where Taiko is still the only based rollup in production, to a world where abundant adoption comes in, and tens of rollups join the ecosystem.

Shasta is a complete redesign of Taiko's protocol, designed from first principles and informed by the experience of running a rollup in production, as well as our collaboration on the minimal-rollup. We've designed Shasta with three principles in mind:

1. Simplicity: simple protocols are key to innovation. When something is simple to understand, it is also simpler to extend and audit. Shasta removes most of the complexity found in earlier protocol design.

2. Efficiency: Ethereum-grade security and properties do not have to come at a higher cost for users. As it turns out, simplifying the protocol also significantly reduces costs. Shasta achieves a 20x reduction in proposing costs and a 5x reduction in proving and finalization costs.

3. Move complexity off-chain: Advances in zk proving have made proving costs and latency drop dramatically. This has allowed us to move a lot of the protocol checks and complexity to derivation and proving.

How does Shasta work?

The protocol is designed around three main contracts, but we've removed all wrappers, unnecessary abstractions and more:

• Inbox: The inbox is the main rollup contract, representing and enforcing the rollup rules on L1 with two main functions:

  • Propose: Accepts blobs, processes forced inclusions (if they’re due), updates the CoreState and emits an event for provers. That's it, no complex accounting or on-chain checks for protocol-wide rules (e.g. gas limits, timestamps, etc.). All that is derived off-chain and enforced by the prover.
    

  • Prove: Process bonds (if the proof is late), calls the zk verifier, and finalizes the chain by syncing the state of L1 to enable withdrawals and L2->L1 messages. The move to sequential proofs was a key change that unlocked significant simplification and efficiency. This means that proposals are proven (and thus finalized) in order.
    
    This removes the need to have on-chain proof conflict detection and to have a different mechanism to aggregate proofs and finalize the chain.
    

• Anchor: It runs as the first transaction of every L2 block, and its main purpose is to inject the state of the L1 into the L2. This allows deposits and L1->L2 messages, and it will also serve as a commitment store for preconfirmation slashing.
  
  We've removed most other complexities and responsibilities from the anchor.
  

• SignalService: the core mechanism for exchanging messages and bringing tokens between the L1 and Taiko. We've simplified by removing complex structures such as HopProofs, while still keeping it backwards compatible (meaning bridges and intent providers don't need to upgrade).

All of the above sounds great, but what are the actual results?

• Proposing new blocks: Before Shasta, proposing new blocks on Taiko could cost up to 1M gas, and the cost scales with the amount of L2 blocks in that batch (because we were posting metadata about each). This increases the cost of proposer operations, which in turn results in higher fees for users.  Shasta reducesproposals cost ~ 45k gas (once the initial warm-up period has passed, and the proposal ring buffer is full). This means a 22x reduction in proposing fees on mainnet.
  

• Proving new batches: Before Shasta, proving a batch cost ~ 500k gas. With zk proof verification accounting for roughly 250,000 gas, execution alone consumed the remaining 250,000. 

Under Shasta, execution costs drop to around 30,000 gas and remain nearly constant regardless of how many batches are being proven. This strongly favors aggregation, allowing more batches to be verified for roughly the same cost.

This is an 8x reduction in gas costs.

But how do these numbers compare to other rollups?

Each rollup has a slightly different way to run validations, proof systems, and L1 to L2 messaging, which makes direct comparisons difficult. But a good starting point is looking at other zk rollups, which all share a similar flow. Data is posted to L1 (a.k.a propose), you prove the transition (a.k.a prove), and then finalize the chain, posting a checkpoint from L2 to L1, against which messages can be verified. This is the result of querying the 7-day average in Dune and projecting the costs after Shasta.

We've removed a lot of code. And when we say a lot, we mean A LOT.

Removing code sounds easy; you just delete it, right? But true simplicity is not easy. We think people will find the Shasta codebase the simplest rollup contract to read, audit and understand. And that's very powerful.

We're proud to say that Taiko is now one of the easiest rollup protocols to understand, even if you're just getting started.

Security has always been Taiko’s top priority. Shasta has been in development for several months, with careful review and testing of every part of the code. The protocol is already running on internal devnets, where preconfers are testing their software to ensure everything works as expected.

Hoodi will be updated in the coming weeks, giving users early access to the latest improvements. Following final testing on Hoodi, the team plans to submit Shasta as a proposal to the Taiko DAO. Activation on mainnet will depend on successful verification and community approval.

Explore open positions on our job board.

Get the latest from Taiko:

• Website: https://taiko.xyz.

• Discord: https://discord.gg/taikoxyz.

• GitHub: https://github.com/taikoxyz.

• Twitter: https://twitter.com/taikoxyz.

• Community forum: https://community.taiko.xyz.

• YouTube: https://www.youtube.com/@taikoxyz.

• Warpcast: https://warpcast.com/taikoxyz.

Contribute to Taiko on GitHub and earn a GitPOAP! You will also be featured as a contributor on our README. Get started with the contributing manual.