solx is a new optimizing compiler for EVM developed by Matter Labs.

solx passes multiple test suites, including:

• Foundry projects
• Hardhat projects
• tests from the solc project
• real-life projects such as UniswapV2 and Mooniswap
• additional tests written by the solx team

Our mid-term goals:

• emit ethdebug for optimized code
• roll out the MLIR codegen to replace Yul and EVM assembly
• further reduce gas usage and bytecode size
• eliminate the need for inline assembly for efficiency

solx documentation is powered by GitHub Pages and provided as an mdBook, while its Markdown sources can be found in this directory. To build the book, follow these instructions.

See also:

• Solidity Documentation
• LLVM Documentation

For the detailed installation and usage guide, visit the respective page of our documentation.

solx consists of three main parts:

1. solx executable from this repository. The repository also contains parts of the compiler front end: Yul and EVM assembly translators.
2. era-solidity, an LLVM-friendly fork of the Solidity compiler, that emits Yul and EVM assembly for solx. Despite the repository name, it is not directly related to either ZKsync or ZKsync Era.
3. era-compiler-llvm, a fork of the LLVM project with an EVM target developed by the solx team.

The most important part of the project is the EVM target in LLVM. You can find its sources here.

To run the unit and CLI tests, execute cargo test at the repository root.

If you have multiple LLVM builds in your system, ensure that you choose the correct one to build the compiler. The environment variable LLVM_SYS_191_PREFIX sets the path to the directory with LLVM build artifacts, which typically ends with target-llvm/build-final. For example:

export LLVM_SYS_191_PREFIX="${HOME}/src/solx/target-llvm/build-final"

If you suspect that the compiler is not using the correct LLVM build, check by running set | grep LLVM, and reset all LLVM-related environment variables.

For reference, see llvm-sys and Local LLVM Configuration Guide.

• Crate solx is licensed under GNU General Public License v3.0
• All other crates are licensed under the terms of either
  • Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
  • MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)
• era-solidity is licensed under GNU General Public License v3.0
• era-compiler-llvm is licensed under the terms of Apache License, Version 2.0 with LLVM Exceptions, (LICENSE or https://llvm.org/LICENSE.txt)

Additionally, this repository vendors tests and test projects that preserve their original licenses:

• UniswapV2
• UniswapV3
• Mooniswap
• StarkEx Verifier
• SHIT

These projects are modified for the purposes of testing our compiler toolchain and are not used outside of this repository.

Visit the project directories to discover the terms of each license in detail. These and other projects are licensed in either per-file or per-project manner.

Email us at [email protected] or join our Telegram group.