Image credit: Shutterstock
Cardano activated its van Rossem hard fork on July 18, moving the mainnet from Protocol Version 10 to Protocol Version 11 without changing its existing Conway ledger era.
The upgrade introduces new Plutus smart contract capabilities, ledger security improvements and more efficient cryptographic operations. It is also Cardano’s first hard fork approved through the network’s full on-chain governance process.
Protocol Version 11 Activated at Slot 192,844,800
The hard fork took effect at 21:44:51 UTC at the boundary between epochs 643 and 644. Cardano remained operational through the upgrade, with no network split or reported mainnet downtime.
The fork is an intra-era upgrade, meaning Cardano remains in the Conway era rather than moving to a new ledger architecture. ADA holders do not need to migrate their tokens, and staked assets remain accessible. Users are advised to keep wallets and related applications updated.
Five Plutus Additions Target Cost and Performance
Protocol Version 11 makes built-in functions available across Plutus V1, V2 and V3. It also adds native arrays, optimized multi-asset value operations, modular exponentiation, improved list handling and BLS12-381 multi-scalar multiplication for cryptographic applications.
The changes are intended to simplify smart contract logic and reduce execution costs. BLS12-381 support gives developers more efficient tools for applications using zero-knowledge proofs and other cryptographic systems.
Ledger Changes Tighten Stake Pool and Voting Rules
The upgrade enforces uniqueness for stake pool verifiable random function keys at the ledger level. It also revises reference input rules and improves protocol parameter error reporting.
Another change moves a Constitutional Committee voting restriction from a mempool check into the ledger rules.
Those updates are designed to make protocol behavior more consistent and reduce edge-case risks in transaction validation and governance processing.
Three Governance Groups Approved the Hard Fork
The hard fork initiation action was ratified on July 13 after receiving 77.63% support from delegated representatives and 52.7% support from stake pool operators. Six Constitutional Committee members found the proposal constitutional, while one did not vote.
The process followed separate deployments on Cardano’s Preview and PreProd test networks. A related Plutus cost model update was enacted on mainnet on June 18, preparing the parameters needed for the new functions unlocked by the fork.
Developers Can Now Use New Plutus Functions
Cardano’s next work shifts to developer adoption of the new Protocol Version 11 capabilities. Developers can now begin using the new Plutus functions as applications update their tooling.
The upgrade leaves Cardano in the Conway era while expanding the smart contract and ledger features available on mainnet.
