"Espresso Testnet Transitions to Permissionless PoS: Addressing Ethereum Ecosystem Fragmentation"

# Espresso Systems Upgrades Testnet Decaf to Permissionless Proof-of-Stake Model Espresso Systems announced on April 25 the upgrade of its Espresso Network testnet, Decaf, to a permissionless proof-of-stake (PoS) consensus mechanism. This transition marks a significant milestone in Espresso Network's path toward full decentralization. Currently, Espresso functions as a confirmation layer to enhance cross-chain interoperability within the Ethereum network. Since its mainnet launch in November 2024, the network has operated in a permissioned setup involving 100 nodes and 22 institutional and community operators across six continents. However, the Decaf upgrade has now transitioned the network to a permissionless environment, allowing open participation. The Espresso Foundation emphasized the importance of this development in a recent tweet: *"Espresso's Decaf testnet now runs on proof-of-stake! This is an important milestone on our journey to unite Ethereum’s fragmented L2/L3 ecosystem with a fast, secure & decentralized interop layer. Mainnet PoS + $ESP token launch coming soon."* # Mainnet Rollout and ESP Token Launch Slated for 2025 Espresso identifies this upgrade as the final rehearsal before its mainnet release, anticipated in 2025. The mainnet, known as "Mainnet 1," will introduce ESP, a native token designed to underpin governance and economic security within the network. # Enhanced Block Finality and Optimized Network Performance The Decaf upgrade is not merely a shift in consensus mechanism—it also brings substantial enhancements to network operations. Espresso Systems has optimized block finality using its HotShot consensus algorithm, reducing the block finalization process from four rounds to three. Additionally, improvements to Espresso's Verifiable Information Dispersal (VID) protocol enable nodes to process data more efficiently. By integrating an erasure coding-based shard distribution system, nodes no longer need to download entire blocks, significantly boosting network efficiency. Espresso Systems reports that these combined upgrades led to an average block confirmation time reduction of about 29% in testing environments. The company anticipates this will positively impact communication speeds across Ethereum's Layer 2 (L2) and Layer 3 (L3) chains. # Preparing for Mainnet and Expanding Participation During this testing phase, the network's existing 22 node operators have been allocated staking shares in Decaf. Following further testing, Espresso plans to expand staking delegation to new operators. Interested individuals or organizations with node operation expertise can submit applications through Espresso Systems' documentation. In the coming weeks, Espresso Systems will provide updates via its official channels, including X (formerly Twitter) and Discord. Announcements will cover Mainnet 1 rollout timelines, ESP token launch details, and processes for onboarding new operators. A staking delegation program will also be introduced to recognize and reward the contributions of existing node operators. # Addressing Ethereum Fragmentation Through Decentralized Interoperability Espresso Systems aims to tackle fragmentation issues within Ethereum's L2 and L3 ecosystems. The network leverages a Byzantine Fault Tolerance (BFT) consensus model to enable fast and reliable cross-chain communication, achieving transaction trust and usability within seconds. The Decaf upgrade represents a pivotal turning point in fulfilling Espresso’s mission to unite Ethereum’s ecosystem layers. The Espresso Foundation emphasized its vision in a statement: *"Espresso envisions a future where all chains operate as a unified system while maintaining their autonomy and speed. We aim to build a decentralized and sustainable network in collaboration with our community."*