The Layer 2 sector is booming, with many of Ethereum’s leading scaling solutions preparing to ship major upgrades.

On March 20, Starknet announced a new roadmap for 2024, prioritizing increasing throughput and performance over the coming months.

Starknet will introduce transaction parallelization with its 0.13.2 version upgrade in Q2 2024. The network will simultaneously execute transactions, speeding up both finality and throughput.

“ERC-20 transfers from different users, for example, will be executed concurrently instead of sequentially,” Starknet said.

Starknet will follow up by integrating a Cairo-native sequencer and virtual machine with its 0.13.3 version in Q3 to unlock further scalability gains by reducing transaction latency. Starknet is also planning future upgrades introducing volition — allowing dApp data to be stored on Starknet rather than the Ethereum mainnet, in addition to data and batching compression.

“One of Starknet’s main goals for the coming months is to improve network performance — specifically throughput — in order to support the expected rise in the number of users and developers on the network,” Starknet said.

Starknet’s updated roadmap follows the project launching support for EIP-4844 — the main fee-saving upgrade included in Ethereum’s recent Dencun fork — as part of its 0.13.1 version. The new version also coincided with the introduction of gas subsidies intended to bring transaction fees down to the levels anticipated following the launch of other fee-saving mechanisms set to go live in the future.

Average transaction fees on Starknet have dropped by 97% since the upgrade went live, according to GrowThePie.

Polygon prepares to introduce EIP-4844

Polygon will introduce support for EIP-4844 with its upcoming Feijoa upgrade, which is scheduled for May.

Polygon noted that its zkEVM rollup is expected to enjoy fee savings of up to around 65% following the upgrade, while EIP-4844 is unlikely to have a significant impact on its PoS Chain’s fees.

Feijoa will also introduce support for KZG commitment verification through EIP-2537 as part of Feijoa.

Optimism to introduce fault proofs

On March 18, deployed fault proofs on the Sepolia testnet, describing its code as comprising the first “open-source, permissionless, feature-complete fault proof system” in the Ethereum ecosystem.

Fault proofs enable permissionless validation across any chain leveraging Optimism’s OP Stack. “This means that withdrawals of ETH and ERC-20 tokens from OP Stack Chains can be initiated without involvement from any trusted third party,” OP Labs said. “It also means that invalid withdrawals can be challenged and removed by any user that wants to participate in the protocol.”

Fault proofs will next go live on OP Mainnet, pending governance approval. OP Labs said future upgrades will negate the need for Optimism’s Security Council to act as a centralized safety net backstopping fault proofs, furthering the protocol’s decentralization.

“Stage 1 still includes a safety net allowing us to block withdrawals and override dispute game results to protect the bridge during the system’s nascent stages,” OP Labs tweeted.

Espresso closes Series B round

In other Layer 2 news, Espresso Systems, the development team behind the Espresso marketplace for shared sequencers, announced the completion of a $28 million Series B round led by Andreessen Horowitz.

“This round of funding will enable us to scale our team and bring a production-ready implementation of Espresso to the ecosystem,” Expresso said.

Espresso’s marketplace allows rollups to “sell the right to build their blocks” to the highest bidding block proposer. This bolsters the decentralization of Layer 2s by eliminating reliance on centralized proprietary sequencing systems.

Both block builders and L2s generate revenue through the marketplace, with bidders spanning Layer 1 proposers, rollup sequencers, and other block proposers.

“Fragmentation and centralization are two of the biggest obstacles in Ethereum’s rollup-centric roadmap,” Espresso tweeted. “Apps scattered across the plethora of L2s lose the composability they are used to enjoying on the Ethereum Layer 1. Shared sequencers address this problem.”

The round also featured participation from leading L2 teams including Offchain Labs, Polygon, and StarkWare, demonstrating a vote of confidence in Espresso’s marketplace from the Layer 2 sector.

Express will launch its fifth testnet deployment next month.