1. Research & development
  2. > Blog >
  3. Announcing Tezos’ 13th protocol upgrade proposal, Mumbai

Announcing Tezos’ 13th protocol upgrade proposal, Mumbai

17 January 2023
Nomadic Labs

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 PtMumbaiiFFEGbew1rRjzSPyzRbA51Tm3RVZL5suHPxSZYDhCEc.

The main features of this protocol upgrade proposal are:

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 Rollups (TORUs) on Mainnet. TORUs were the first optimistic rollup implementation on Mainnet enabled with Jakarta mid 2022, and the first step of the scalability roadmap presented last March.

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 Mainnet.

The changelog provides a detailed list of changes, and a general technical overview of Mumbai can be found in the protocol proposal’s technical documentation.

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/.

Smart Rollups and Epoxy testers wanted

First, Smart Rollups will be active on Mumbainet soon. Functioning rollups implemented in Rust are currently running on Mondaynet. We 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 TPS.

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 Mondaynet.

Broad testing and feedback from the ecosystem is invaluable in our efforts to minimize the risk of undetected issues upon Mainnet activation.

Read more about Tezos testnets here, and don’t hesitate to reach out in the Tezos Developer Slack or in the Tezos Discord if you need help getting started.

Anyone interested in getting started with building a smart rollup node can reach out to contact@nomadic-labs.com.