Analysis of Ethereum Fusaka Upgrade: 12 Core Proposals for Scaling Evolution

At the 214th Ethereum execution layer core developer meeting held recently, participants reached a consensus on the final scope of the Fusaka upgrade. In addition to the originally planned content, a new proposal (EIP 7939) was added, bringing the total number of EIPs covered by this upgrade to 12. This marks the official transition of Fusaka from the planning stage to the substantive implementation stage.

As the largest hard fork bundled upgrade since The Merge, the industry generally expects that if Fusaka can be launched as planned by the end of 2025, it will bring significant improvements to the L2 data space. In the next 1-2 years, L2 transaction fees may further decrease, thereby consolidating Ethereum's market position.

The Continuous Evolution of Ethereum's Scalability Roadmap

The scalability issue of Ethereum has been a major barrier to the high on-chain costs of the mainnet and the widespread adoption of DApps. According to publicly available data from April this year, the current throughput of Ethereum L1 is 15 transactions per second, and the Gas limit has recently increased to 36 million, which is about a sixfold increase over the past 10 years.

At the same time, the changes at the Ethereum L2 level are more significant. The current L2 throughput has reached approximately 250 TPS, achieving substantial progress in scalability. This is not only reflected in the data, but many users have also felt the decrease in on-chain operation costs and the increase in speed.

In the past year, the transaction fees of several mainstream L2 networks have generally dropped to around $0.01 or even lower, achieving a decrease of one or more orders of magnitude compared to before. The daily Gas costs of the Ethereum mainnet have also become noticeably more affordable.

This transformation stems from Ethereum's strict enforcement and continuous iteration of its roadmap. Looking back at the key upgrades in recent years:

• In 2022, the Merge upgrade achieved the transition to the PoS mechanism, significantly reducing energy consumption and freeing up execution layer bandwidth for subsequent upgrades.
• The 2024 Dencun upgrade introduces the Blob data mechanism, providing low-cost temporary storage space for L2, significantly reducing Rollup costs.
• The recent Pectra upgrade has optimized the validator operation process and enhanced the flexibility of participating in the PoS system.

The upcoming Fusaka upgrade is a key step in this process.

According to the latest statements from senior officials of the Ethereum Foundation, the Fusaka plan is set to launch its mainnet in the third or fourth quarter of 2025, which will implement several core EIPs, including PeerDAS data availability sampling, further pushing Ethereum to break through performance bottlenecks and move towards mainstream applications.

From The Merge to Dencun, Pectra, and then to Fusaka, Ethereum is systematically moving towards its long-term goal of building a global network that is secure, scalable, decentralized, and sustainable.

Fusaka Upgrade Overview

This upgrade includes 12 core EIPs that cover multiple technical dimensions such as data availability, node lightweighting, EVM optimization, and the collaborative mechanism between the execution layer and the data layer.

The most attention-grabbing is EIP-7594(PeerDAS), which introduces the "Data Availability Sampling (DAS)" mechanism. This allows validators in the network to complete validation by downloading only a portion of the Blob data, without the need to fully store all data. This greatly reduces the network burden, improves verification efficiency, and lays the foundation for the large-scale transaction processing capabilities of L2.

The concept of "Blob" here can be traced back to EIP-4844 introduced in the Dencun upgrade of 2024. As an important milestone for Ethereum in 2024, the Dencun upgrade enabled transactions carrying Blobs for the first time, allowing L2 networks to choose not to use the traditional calldata storage mechanism, thereby significantly reducing the Gas fees required for transactions and transfers on L2.

Carrying Blob transactions essentially embeds a large amount of transaction data into the Blob, significantly reducing the storage and processing burden on the Ethereum mainnet. This data does not count towards the Ethereum mainnet state, directly addressing the L1 cost issues related to data availability, ensuring that L2 platforms can offer more economical and faster transactions while not compromising the security and decentralization of Ethereum.

It is worth mentioning that the Pectra upgrade in May has increased the Blob capacity from 3 to 6. There is a view that ideally, Fusaka will expand the Blob capacity to 72 per block (, initially growing to 12~24), and in the future, if DAS is fully implemented, the theoretical maximum capacity could reach 512 Blobs per block.

Once implemented, the processing capacity of L2 is expected to soar to tens of thousands ( TPS ), significantly enhancing the usability and cost structure of high-frequency interaction scenarios such as on-chain DApps, DeFi, social networks, and games.

At the same time, Fusaka plans to achieve a lightweight state and node structure by introducing Verkle trees, which will not only significantly compress the size of state proofs, making light clients and stateless validation possible, but also help promote the decentralization of Ethereum and its adoption on mobile devices.

In addition, Fusaka also focuses on the flexibility and performance bottlenecks of the virtual machine layer (EVM), including the following proposals:

• EIP-7939(CLZ opcode): Efficiently implements bitwise operations to accelerate cryptographic calculations.
• EIP-7951( secp256r1 replacement support ): Enhancing compatibility with Web2 and enterprise architecture.
• EIP-7907: Expand the contract size limit to support the deployment of more complex logic, enhancing developer flexibility.

To ensure that scaling does not affect network stability, Fusaka has also introduced EIP-7934 to set block size limits, ensuring that blocks do not become too heavy due to Blob scaling, and has adjusted Blob usage fees through EIP-7892/EIP-7918 to prevent resource abuse and dynamically match supply and demand fluctuations.

The Watershed of Ethereum Scalability and Experience

Overall, Fusaka is not just a technological upgrade, but is also expected to lay the foundation for a bridge on multiple key levels "from scalability to usability."

For Rollup developers, this means lower data writing costs and more flexible interaction space. For wallet and infrastructure providers, it means supporting more complex interactions and heavier load node environments. For end users, this will bring lower experience costs and faster response for on-chain operations. For enterprises and compliant users, EVM scaling and state proof simplification will also make on-chain interactions easier to integrate into regulatory systems and large-scale deployments.

However, it is still necessary to maintain a cautiously optimistic attitude. Currently, Fusaka is undergoing testing on multiple test networks, and the final launch date may change. In an optimistic scenario, Fusaka is expected to complete its mainnet deployment by the end of 2025, which could become another important milestone in Ethereum's history following The Merge.

Overall, Fusaka is not limited to enhancing on-chain scalability; it represents a key step for Ethereum in transitioning to mainstream commercial applications and ordinary users, and is expected to provide a technical foundation for the next phase of the Rollup ecosystem, enterprise-level Dapps, and on-chain user experience.

The true watershed moment for Ethereum to achieve large-scale mainstream adoption may be approaching.