Skip to content


Repository files navigation


Act is a formal specification language, designed to allow for the construction of an exhaustive, mathematically rigorous description of evm programs. Act allows diverse toolchains to interoperate on a single specification, with each generating and exchanging different kinds of knowledge. It has a built-in analysis engine that can automatically prove properties about the specification itself, as well as an integrated symbolic execution engine (based on hevm) that can prove equivalence between a specification and a given bytecode object. Finally, specifications can be exported into higher level reasoning tools (e.g. theorem provers, economic analysis tooling), allowing for the verification of properties of almost arbitrary complexity, all with a proof chain right down to the bytecode level.

It extends on the previous Act project.

More in depth documentation can be found in The Act Book.


With nix:

nix build


Enter a nix-shell to get the dependencies of the project:

nix develop

you can then use cabal as normal:

cd src
cabal build # build
cabal repl  # enter a repl instance

to execute the unit tests:

make test # run all tests
cd src && cabal v2-test # run haskell tests

To update the project dependencies run:

nix flake update