Experimental Core Solidity Compiler

This is a prototype implementation of Solidity's new type system. It is functional and can produce executable EVM code. It has not been optimized for UX, and if you're looking for an industrial compiler with a clean UX and good error messages you will not find it here. The compiler contains bugs. You should under no circumstances be using this in a production setting.

A high level overview of the lnaguage and it's design can be found in the Core Solidity Deep Dive post on the Solidity blog. A pen and paper formalization of the type system is defined in the ./spec directory, and pdf builds are available as artifacts from the Spec PDF workflow.

Bug reports and feedback are very welcome.

Development

# enter a development shell with all required dependencies
nix develop

# enter a repl
cabal repl

# build the project
cabal build

# run the tests
cabal test

# run the CI pipeline locally
nix build

Using nix and flakes

This project uses nix flakes. If you haven't already you should add the following to ~/.config/nix/nix.conf (user local) or /etc/nix/nix.conf (system wide) to disable errors about experimental-features:

experimental-features = nix-command flakes

Alternatively, the determinate nix installer installs nix with flakes enabled automatically.

Usage

Compilation

The compiler is currented implemented as two binaries:

1. sol-core: typechecks, specializes, and lowers to the core IR
2. yule: lowers core files to yul

# produces `output1.core`
$ cabal run -- sol-core -f <input>

# produces an output.yul
$ cabal run -- yule output1.core -o output.yul

Running Code

The runsol.sh script implements a small pipeline that executes a core solidity contract by compiling via sol-core -> yule -> solc, and then using geth to execute the resulting EVM code.

It takes the following arguments:

> ./runsol.sh
Options:
  --runtime-calldata sig [args...]  Generate calldata using cast calldata
  --runtime-raw-calldata hex        Pass raw calldata directly to geth
  --runtime-callvalue value         Pass callvalue to geth (in wei)
  --debug-runtime                   Explore the evm execution in the interactive debugger
  --create true|false               Run the initcode to deploy the contract (default: true)
  --create-arguments sig [args...]  Generate calldata using cast calldata
  --create-raw-arguments hex        Pass raw calldata directly to geth
  --create-callvalue value          Pass callvalue to geth (in wei)
  --debug-create                    Explore the evm execution in the interactive debugger