Tiramisu

Tiramisu is a "Layer Two" system for scalable token transfers that prioritizes simplicity.

Summary

Tiramisu is a framework for performing ERC20 token transfers at a fraction of the cost of a standard transfer.

It accomplishes this by aggregating transactions and committing them into blocks. However, it does not perform any on-chain computation for the transactions themselves. Instead, it simply includes a merkle root of the new account state along with the transaction data for each block. If some part of a block is invalid, anyone can submit a proof to that effect within a challenge period. Should they do so, they earn a reward and trigger a roll-back of the state.

Tiramisu is a member of the group of "fraud proof rollup" (or "optimistic rollup") Layer Two technologies. That being said, Tiramisu prioritizes simplicity over raw scalability or generalizability — it designates a single block producer, and the only permitted operations are deposits, transfers, withdrawals, and authorization of additional signing keys.

These operations are broken down into two high-level categories:

• Hard transactions, including deposits and direct withdrawals or signing key additions, can only be initiated from a corresponding account on mainnet. These are placed in a queue as soon as the Tiramisu contract is called, and must be processed by the block producer in the order they are received.
• Soft transactions, including transfers and standard withdrawals or signing key modifications, require a signature from a designated signer, and the block producer can choose whether or not to include a given soft transaction in a block.

See the specification for a more detailed overview of the design decisions behind Tiramisu.

⚠️ Warning: these contracts and libraries have not been audited and are not yet production-ready! ⚠️

Table of Contents

• Install
• Usage
• Additional Information

Install

To install locally, you'll need Node.js 10 through 12 and Yarn (or npm). Then, perform the following:

$ git clone https://github.com/dharma-eng/Tiramisu.git
$ cd Tiramisu
$ yarn install

Once you've successfully pulled down the code and installed all dependencies, you'll need to compile both the application code (using TypeScript) as well as the contracts (using Truffle):

$ yarn build:ts   # compiles app/ and places output in dist/
$ yarn build:sol  # compiles contracts/ and places output in build/

Usage

To run all the typescript tests in test/tests/:

$ yarn test:app

You can also run tests directly if you prefer for the blockchain class, the state wrapper class, or the state machine class that executes transactions:

$ yarn test:blockchain
$ yarn test:state
$ yarn test:transactions

To generate application test coverage using nyc:

$ yarn test:coverage:app

To generate contract test coverage using Truffle with the solidity-coverage plugin:

$ yarn test:coverage:sol

To run contract linters:

$ yarn lint

Additional Information

This repository is maintained by @0age, @d1ll0n, and @anna-carrol.

Have any questions or feedback? Join the conversation in the Dharma_HQ Discord server.