
Athens
Increased gas limit per block and reduced the roll size from 10,000 ꜩ to 8,000 ꜩ

Babylon
Introduced a more robust version of the blockchain’s consensus algorithm (Emmy+); simplified smart contract development; refined the delegation process.

Carthage
Increased gas limit per block and per operation; improved the accuracy and resiliency of the formula used for calculating baking and endorsing rewards.

Delphi
Improved gas costs. Reduced storage costs by a factor of 4 to reflect improvements in the underlying storage layer.

Edo
Added Sapling and BLS12-381 to enable privacy-preserving smart contracts and tickets for native permissions. Updated amendment process by lowering period length to 5 cycles and adding a 5th Adoption Period.

Florence
Doubled maximum size of operations, which more than doubled the maximum size of smart contracts. Furthered gas optimizations as well as sped up gas arithmetic by a factor of ten. Enabled more intuitive smart contract development by adopting depth-first execution order. Deactivated unused Test Chain in the Economic Protocol, resulting in more streamlined amendment process.

Granada
Introduced Liquidity Baking, which mints a small amount of tez every block and deposits it inside of a constant product market making smart-contract. This incentivizes large amounts of decentralized liquidity between tez and tzBTC. Included several improvements that led to a 3-6x decrease in gas consumption of popular contracts.

Hangzhou
Introduced several improvements such as views which give smart contracts the ability to read the storage state of other smart contracts, timelock encryption to serve as a countermeasure against Block Producer Extractable Value, caching to provide faster access at lower gas costs to data that is accessed regularly, and a global table of constants to facilitate development of more complex smart contracts.

Ithaca
Introduced Tenderbake, a new and significantly upgraded Tezos consensus algorithm, which enables fast finality and improved scalability for the Tezos blockchain. Introduced a variety of other changes that improve the baking experience, such as reducing the amount of tokens required to be a validator, a rework of the baking and endorsement rewards mechanism, and more.

Jakarta
Introduced Transaction Optimistic Rollups (TORUs), an experiment into enshrined rollups, leading to increased throughput, lower fees, and a pathway to significantly increased long-term scalability. Introduced improvements to tickets and sapling, enabling improved network privacy features and increased decentralization for Tezos tokens.

Kathmandu
Enabled smart contract optimistic rollups on bleeding edge testnets, preparing the protocol for the future full integration of SCORUs. Introduced the first steps of pipelined block validation, aiming to streamline the block validation process. Implemented improved randomness with VDFs, event logging in smart contracts, and more.

Lima
Pipelining improvements separating the validation from the application of operations will enable higher throughput. Consensus keys introduced allowing bakers to change their key for signing blocks and consensus operations. Tickets ownership updates now included in transaction receipts, which help indexers. And more.

Mumbai
Block times cut in half to 15 seconds with the completion of improved block validation pipelining. Smart Rollups fully activated on Mainnet which will support dramatic gains in throughput, and allow anyone to deploy decentralized WebAssembly applications. Tickets can now be transferred between user (implicit) accounts, and more.