Changelog

Reverse-chronological history of Espresso network releases, with links to release notes and announcements.

This page lists Espresso network releases in reverse-chronological order. For live network details (endpoints, contract addresses, container images), see Networks.

Proof of Stake (Mainnet) - March 2026

Activated permissionless validator participation on Espresso through delegated proof-of-stake. Previously deployed on Decaf testnet in April 2025.

Mainnet (testnet release) - April 2025

Upgraded Espresso to support permissionless participation through delegated proof-of-stake. The upgrade went live on Decaf testnet on April 18, 2025; Ethereum mainnet upgrade followed March 4, 2026.

• Permissionless validator set (top 100 by delegated stake per epoch)

• New stake table and ESP token contracts

• API moves from v0 to v1

• See Chain Migration Guide for integration changes

Mainnet 0 - October 2024

First production release of Espresso. Initial operator set: 20 node operators running 100 nodes. Initial block size 1 MB with planned scaling to 5 MB.

Decaf Testnet - September 2024

Launched Decaf as Espresso's persistent testnet alongside the upcoming Mainnet release. Expanded operator set to 24 operators running 100 geographically distributed nodes.

Cappuccino Testnet - May 2024

Onboarded 10 operators running 100 geographically distributed nodes. Tiramisu DA layer upgraded with VID support. Added Arbitrum Nitro fraud-proof support, enabling Arbitrum chains to run fully productized on Espresso. Deprecated by Decaf.

Gibraltar Testnet - January 2024

First integration with Arbitrum Nitro, along with progress on Savoiardi (a VID implementation forming the backbone of the Tiramisu DA solution). First testnet run by external node operators in collaboration with Blockdaemon. Deprecated.

Cortado Testnet - September 2023

First integration with the OP Stack, resulting from Espresso's work on a leader election interface for the OP Stack. Public testnet deployed with two chains of different stacks: an OP Stack chain (Vienna, by Caldera) and a Polygon zkEVM chain. Deprecated.

Doppio Testnet - July 2023

Second testnet of Espresso. Includes integrations with both a minimal chain example and the Polygon zkEVM stack. Announcement · Public testnet announcement. Deprecated.

Americano Testnet - November 2022

First testnet of Espresso. Announcement. Deprecated.