Cardano launched the first live test of its next-generation consensus protocol on June 23, 2026. The testnet, named Musashi Dojo after legendary samurai Miyamoto Musashi, is the first live validation of Ouroboros Leios — a redesign of Cardano's consensus layer that Input Output Global (IOG) projects will raise peak transaction throughput 30 to 65 times above current levels.

How Ouroboros Leios works

The Leios protocol runs as an overlay alongside the existing Ouroboros Praos system. During high-demand periods, it issues larger "endorser blocks" carrying more transactions than standard blocks, without changing the underlying proof-of-stake security model. The official Leios roadmap sets a peak target of more than 1,500 transactions per second and block propagation under five seconds globally. Cardano currently processes roughly 800,000 transactions per month; IOG's stated target is more than 27 million.

Five phases: Earth to Void

The Musashi Dojo testnet runs through five sequential phases. Earth validates basic protocol design. Water explores protocol parameters. Fire tests Leios under real-world conditions, including stake pool operator onboarding. Wind runs adversarial scenarios. Void prepares the protocol for mainnet, anticipated for late 2026 or early 2027.

Carlos López de Lara, IOG's product manager for Leios, described the design to CryptoBriefing as "an overlay protocol that works alongside Praos, introducing larger endorser blocks during periods of high demand while maintaining the security model." He told U.Today: "The road to Cardano 2030 runs straight through Leios."

The build behind the launch

Reaching today's launch required more than 705,000 lines of code and 5,700 development updates, according to a June 16 milestone report covered by Cryptonomist. Cardano co-founder Charles Hoskinson said the team had done "things that we could only have dreamed of when I started the project," according to BeInCrypto.

A testnet, not a mainnet upgrade

Musashi Dojo is a proof-of-concept environment, not a mainnet rollout. The testnet either validates the design or surfaces what still needs fixing. Results determine the path to the Void phase and a production-grade release.

ADA was trading near $0.185 at the time of the testnet launch, roughly 94 percent below its September 2021 all-time high of $3.09.