coindesk.com
As blockchains push for more decentralization, the crucial component known as the "sequencer" is becoming a bigger focus.
Espresso is one of the leading projects working on "shared sequencing." The project relies on permissionless network nodes.
Andreessen Horowitz's a16z Crypto is viewed as one of the top venture capital firms. Polygon Labs was also an investor.
Espresso, a leading specialist in the emerging blockchain field of "shared sequencing," has raised $28 million in a series B round led by venture capital firm Andreessen Horowitz's a16z Crypto, according to a press release seen by CoinDesk.
The investment round closed in February, and the funding will be used to continue to build out Espresso’s products, invest in the broader rollup ecosystem, and hire additional people for Espresso.
Layer-2 firm Polygon Labs also participated in the investment round, a spokesperson for Espresso told CoinDesk over email.
Sequencers are responsible for verifying and batching transactions made on layer-2 blockchains and then sending them back to a layer 1 chain like Ethereum to be settled. The main criticism with sequencers today is that they are often prone to centralization concerns – in many cases run by a single operator – and present risks, such as network censorship or single points of failure.
Read More: Modular Blockchain Astria Raises $5.5M for Shared Sequencer Network
Solutions like Espresso’s shared sequencer – relying on a separate, permissionless network nodes – are designed to help address the concern
Espresso has previously stated that it's created a proof-of-concept integration with Polygon’s zkEVM stack in the Espresso Sequencer, and with Optimism’s OP Stack, both on testnet.
“Rollups have enriched the greater Ethereum ecosystem with horizontal scalability and a diversity of execution environments, but at the expense of fragmentation—apps across rollups do not have the same shared liquidity and interoperability as apps on the Ethereum L1,” Ben Fisch, CEO of Espresso Systems, said in an interview with CoinDesk over email. “Shared sequencing enables rollup users to regain the experience of being on one Ethereum chain.”
Espresso’s main product is the shared sequencer, but beyond that the company is building out a marketplace for shared sequencing “where rollups can sell the right to build their blocks to proposers who bid for these rights,” according to the press release. “Proposers can also bid on multiple rollup blocks, which would see them act as a shared proposer for multiple chains at once.”
Espresso is currently on its fifth iteration of testnet, and will hit mainnet later this year, Fisch shared with CoinDesk in an email.
Read more: ‘Sequencers’ Are Blockchain’s Air Traffic Control. Here’s Why They’re Misunderstood