This is a joint post from Nomadic Labs, Marigold, TriliTech, Oxhead Alpha, Tarides, DaiLambda & Functori.
We’re happy to announce that Mumbai, our next Tezos protocol proposal,
is ready. As usual, Mumbai’s ‘true’ name is its hash, which is
The main features of this protocol upgrade proposal are:
Smart rollups are activated: Smart rollups are fully operational on Mainnet offering a powerful scaling solution. Anyone can deploy decentralized WebAssembly applications with dedicated computational and networking resources.
Epoxy makes its first appearance: Validity Rollups (aka ZK-rollups) arrive on the Mondaynet testnet. Epoxy allows for instant finality due to SNARK’s proof-of-validity.
Block time reduced to 15 seconds: With improved pipelining fully deployed, block propagation times are significantly reduced – this allows for the minimal block time to be cut in half to 15 seconds!
RPCs for ticket balances: Two new RPC endpoints were added to improve the visibility of ticket ownership.
/all_ticket_balances returns a complete list of tickets owned by a given contract. And /ticket_balance returns the given-contract’s balance of the ticket with specified ticketer, content type, and content.
New Michelson operations: Michelson opcodes AND, OR, XOR, NOT, LSL and LSR were extended to support logical operations on bytes, similar to those on nat. And an opcode was added to convert between bytes and nat.
To learn more about Mumbai’s contents, see our full preview post.
In addition to these exciting new features and steady progress, the
Mumbai proposal disables Transaction Optimistic
Mainnet. TORUs were the first optimistic rollup
Mainnet enabled with
mid 2022, and the first step of the scalability roadmap
Transaction rollups were always intended to be an temporary solution,
as clearly indicated by the sunset they were released with. Now that
smart rollups are reaching Tezos
Mainnet, it makes little sense to
keep transaction rollups enabled, as this functionality can easily be
implemented through Smart Rollups. It is important to understand that,
if Mumbai is voted in by the community, the transaction rollup subsystem
will be completely disabled as soon as the protocol becomes activate on
Mainnet. This means tickets deposited on transaction rollups will be
lost forever, and operators will not be able to reclaim their ꜩ 10,000
bond. Currently, no transaction rollups have been originated on
Note that, if Mumbai is voted in by the community, upgrading to Octez
v16.0 (or later) will be necessary for participating in consensus. A
release candidate for Octez v16.0 will be published in the coming
days, and a dedicated protocol test network
Mumbainet is also
scheduled to begin soon. More information about the test network will
be available on https://teztnets.xyz/.
First, Smart Rollups will be active on
Mumbainet soon. Functioning
rollups implemented in Rust are currently running on
highly encourage ecosystem participants to experiment and build with
these rollups. In roughly 2 months they are expected to activate on
Mainnet, assuming Mumbai is voted in. Smart Rollups are instrumental
in our efforts to reach 1 millon
Second, Epoxy - Tezos’ validity rollup (aka ZK-rollup) solution makes
its way onto
Mondaynet. It’s not, however, part of the Mumbai
protocol upgrade, as more time needs to be spent on validation,
testing, and integration with ecosystem tools before they can be
activated on Mainnet. We ask ecosystem participants to start
experimenting with Epoxy on
Broad testing and feedback from the ecosystem is invaluable in our
efforts to minimize the risk of undetected issues upon
Anyone interested in getting started with building a smart rollup node can reach out to firstname.lastname@example.org.