Cardano Leios, an upgrade aimed at increasing the blockchain’s data throughput, has become the primary milestone for what founder Charles Hoskinson describes as a “complete” Cardano network. While this standard reflects Hoskinson’s personal view and not the project’s formal development roadmap, it underscores the significance he assigns to the Leios upgrade reaching the mainnet.
Hoskinson names Leios the finishing touch
Hoskinson clarified that Cardano would meet his definition of completion only after the Leios throughput upgrade is operational on the mainnet. His statement positions Leios as the final major component in Cardano’s original framework, following developments such as decentralized consensus, on-chain governance, formal methods, the eUTXO ledger, Plutus smart contracts, scalability, and multiple independent node clients.
Hoskinson described Leios as the ultimate element to complete Cardano in his personal vision, adding that its progress is relevant to millions of ADA holders, not just the development team.
He emphasized that Cardano’s governance can still enable future upgrades and changes, indicating that this milestone reflects only his subjective view on the platform’s maturity rather than an end to all progress.
In addition, Hoskinson hinted at an ambitious privacy-focused partner network called Midnight, which he called the “magnum opus” of his career. However, he stopped short of releasing technical details, a launch timeline, or specific features for this new project.
Hoskinson stated that he was developing a unique concept for Midnight, which he claimed could address many current issues in the cryptocurrency industry, but he did not provide a design or product roadmap.
Cardano is a public blockchain platform known for its approach to security and scalability through peer-reviewed research and layered architecture. Hoskinson, who previously co-founded Ethereum, leads its development through IOHK (Input Output Hong Kong).
Leios is an extension to Cardano’s Ouroboros proof-of-stake protocol, designed to increase data throughput. With Leios, block producers create larger endorser blocks alongside standard Praos blocks, while a committee weighted by staking share certifies the transaction data. This structure allows increased capacity without replacing the current Praos consensus mechanism.
Endorser transactions that pass committee certification are admitted to the ledger using the existing chain rules. The aim is to scale Cardano’s handling of transaction data, ensuring increased performance without compromising consensus.
Mini dictionary: Ouroboros Praos, the consensus protocol currently used on Cardano’s mainnet, is a proof-of-stake algorithm that manages block production and staking rewards while maintaining security and decentralization.
Testnet milestones and technical context
The Leios system is still in public testing. The Musashi Dojo testnet, launched on June 23, reached a peak throughput of 26.8 transaction kilobytes per second (TxkB/s) in its “Earth” phase. By comparison, Cardano’s mainnet running only Praos records approximately 4.51 TxkB/s, placing the testnet outcome at about six times current production capacity.
| Metric | Praos Mainnet | Leios Testnet (Musashi Dojo) |
|---|---|---|
| Peak throughput (TxkB/s) | 4.51 | 26.8 |
| Tested mode | Production | Public testnet (Earth phase) |
It is important to distinguish TxkB/s from transactions per second (TPS). The TxkB/s figure reflects the amount of transaction data processed per second, not the number of transactions themselves. This metric quantifies data load, which may increase with transaction complexity or size and does not imply direct TPS growth.
The Musashi Dojo trial involved full protocol usage, including Praos and endorser blocks, stake voting, and certification. Testing generated over 127,000 blocks and 30,000 endorser blocks, along with nearly 8,000 certificates. Developers identified five technical incidents such as chain forks and synchronization issues, describing these as implementation bugs rather than design flaws.
Linear Leios, representing the initial rollout, is expected in the first phase of the Dijkstra hard fork set for late 2026. Its deployment will depend on Cardano’s on-chain governance approval by DReps, stake pool operators, and the Constitutional Committee. Stake pools will need to register BLS keys for voting, and throughput parameters will be raised gradually in stages after the upgrade’s activation.
