The Cardano community is commemorating the sixth anniversary of the Shelley upgrade, a turning point that enabled staking on the Cardano blockchain and set the network on its path toward greater decentralization.
Shelley upgrade brings staking and decentralization
Shelley succeeded the Byron era, which marked Cardano’s mainnet launch in September 2017 alongside the introduction of the ADA cryptocurrency. Byron laid the foundational architecture, but Shelley delivered Cardano’s first major step toward optimizing decentralization.
Highlighting the achievement, the official Cardano community X account pointed to several milestones shaped by Shelley, including the launch of decentralized block production, the rollout of staking rewards, and the ongoing, uninterrupted operation of the blockchain since the upgrade. In a recent post, the community stated that Cardano “hard forked into Shelley. Stake pools, decentralised block production and staking rewards became a thing. The chain hasn’t stopped since.”
Shelley introduced stake pools, decentralized block production, and staking rewards to Cardano, which has operated continuously since the upgrade, according to the Cardano community X account.
Initially, Cardano functioned as a federated network with only a limited number of nodes running the protocol. The early 2020 Byron reboot set the trajectory for decentralization by implementing a modular node design, which paved the way for future scalability and upgrades.
The Shelley era commenced in July 2020, bringing with it stake pools and delegation features. These changes introduced a decentralized ledger structure and established a new economic incentive system via ADA staking.
Stake pools and growing ecosystem
By the first quarter of 2021, Cardano’s stake pool operator (SPO) community began producing all new blocks on the network, signifying a complete shift to community-driven block production. At present, 2,882 active stake pools collectively manage 21.56 billion ADA in live stake, according to Cexplorer.
| Period | Stake Pools | Live ADA Stake |
|---|---|---|
| July 2020 (Shelley launch) | ~100 | Not reported |
| Q1 2021 | ~2,000 | Rising rapidly |
| July 2024 | 2,882 | 21.56 billion ADA |
Major upgrades ahead: Ouroboros Leios and Van Rossem hard fork
Six years since Shelley, Cardano is now preparing for its most significant scaling initiative yet: the Ouroboros Leios upgrade. This protocol development is being tested on a public network known as Musashi Dojo.
Ouroboros Leios, named after a new consensus protocol, is structured into five sequential phases, each inspired by a chapter from Musashi’s Book of Five Rings: Earth, Water, Fire, Wind, and Void. These stages guide the protocol through technical validation, performance testing, adversarial assessment, and preparation for final mainnet launch.
Input Output Global, the technology company driving Cardano research and development, aims for Ouroboros Leios to deliver a five to twenty-fold increase in Cardano’s base layer throughput. A mainnet hard fork activating the upgrade is slated for later in 2026.
Last July, the Van Rossem hard fork went live, establishing the framework for the coming Dijkstra era hard fork. The Dijkstra fork will be responsible for integrating Ouroboros Leios into the Cardano mainnet.
Mini dictionary: Ouroboros Leios, an upcoming Cardano consensus protocol upgrade, is designed to substantially increase transaction throughput and network scalability, using a phased rollout on public testnets before mainnet adoption.
