Cardano (ADA): A Research-First L1 Built in Careful Stages
Ouroboros proof of stake, eUTXO and on-chain governance
Cardano is a research-driven blockchain led by Ethereum co-founder Charles Hoskinson. It adds designs checked in academic papers one stage at a time, and ADA is its own coin.
1. Who built it: the three pillars
Cardano was built mainly by IOHK (now IOG, Input Output), founded in 2015 by Charles Hoskinson and Jeremy Wood. With the Swiss Cardano Foundation and EMURGO, a business arm born in Japan, it formed the “three pillars”; since 2023 the member body Intersect has coordinated development. The mainnet opened in September 2017.
Its eras carry historical names: Byron, Shelley, Goguen, Basho and Voltaire. Shelley brought full proof of stake in 2020, Alonzo opened smart contracts in September 2021, and the Chang (2024) and Plomin (2025) upgrades added on-chain governance. On the Crypto Nation map, ADA is the city-hall tower in the middle of Cardano City.
2. How it works: Ouroboros and eUTXO
Cardano runs on Ouroboros, a proof-of-stake protocol in which stakers produce the blocks. ADA holders delegate to stake pools without locking their coins, so delegated ADA can still move at any time. Time is split into five-day epochs, and rewards are calculated each epoch.
The ledger, eUTXO, extends Bitcoin’s UTXO model of leftover transaction pieces. Results are easy to predict, but programming differs from Ethereum’s account model, which early developers found hard. Contracts are written in languages such as Haskell-based Plutus or Aiken, and ADA’s supply is capped at 45 billion.
3. Governance and recent milestones
Since a constitution was ratified in 2025, delegated representatives (DReps), stake pool operators and a constitutional committee decide upgrades and treasury budgets together. In July 2026 the van Rossem hard fork, approved this way, moved the network to protocol version 11 and cut Plutus costs. Ouroboros Leios, built to raise throughput sharply, is planned for the next Dijkstra hard fork.
Around it, Midnight, a privacy partner chain developed by IOG, opened its mainnet in March 2026 after distributing its NIGHT token, and Cardano stake pool operators can validate it too. Hydra, a layer-2 technology for fast off-chain exchanges, is in development.
4. Things to know
Cardano’s careful research culture built trust but also drew long criticism that features arrive slowly, and observers note the strong influence of IOG and Charles Hoskinson even under on-chain governance. In 2025 allegations surfaced about how early ADA vouchers were redeemed; an outside investigation published by IOG found the process had been handled properly.
On November 21, 2025, a malformed delegation transaction triggered an old software bug and split the network in two. Node updates reunited the chain and no user funds were reported lost, but it showed that software flaws can still shake a decentralised network. Big upgrades such as Leios can slip, so separate plans from what has shipped.
Written from information public up to October 2026. It does not recommend or rate any coin and is not investment advice. If something is wrong, please tell us through the contact page.