Skip to content
Switch branches/tags

Latest commit


Git stats


Failed to load latest commit information.
Latest commit message
Commit time

K Semantics of Eth2.0 Beacon Chain

An executable, formal specification of Eth2.0 Beacon Chain Phase 0 specification in the K framework. The project provides:

  • an executable model of the beacon chain state transition function that is validated against the standard test suite of the beacon chain, and
  • testing and rule-based test coverage analysis on the model's K specification

The specification and test coverage analysis results are described in the technical report:

PDF An Executable K Model of Ethereum 2.0 Beacon Chain Phase 0 Specification



These dependencies are pulled from KEVM, but with git-lfs added.


apt install --yes                                                           \
    autoconf bison clang-8.0 cmake curl flex gcc git-lfs libboost-test-dev  \
    libcrypto++-dev libffi-dev libjemalloc-dev libmpfr-dev libprocps-dev    \
    libsecp256k1-dev libssl-dev libtool libyaml-dev lld-8.0 llvm-8.0-tools  \
    make maven opam openjdk-8-jdk pandoc pkg-config python3 python-pygments \
    python-recommonmark python-sphinx time zlib1g-dev protobuf-compiler     \

git submodule update --init --recursive


In addition to the dependencies listed at KEVM, install:

brew install jemalloc llvm libyaml git-lfs cryptopp

Build K and K's dependencies, and build local version of libsecp256k1.

git submodule update --init --recursive
make deps libsecp256k1


make build


Get YAML test vectors:

make test-split

Run the tests:

make test


The main model files and testing scripts, which are located in the directory of this README, are as follows:

  • constants-minimal.k: definitions of system-wide constants for testing purposes, corresponding to the "minimal" test suite of beacon chain
  • types.k: type definitions and basic operations corresponding to Python data types and builtin functions and beacon-chain-specific types and operations needed by the model
  • config.k: specification of a K configuration defining the structure and components of the beacon state
  • hash-tree.k: specification of the hash-tree (merkle-tree) computation functions on beacon-chain data structures
  • beacon-chain.k: specification of the beacon chain state transition function and all its supporting sub-functions
  •, scripts that load beacon chain implementation-independent tests into K.

Getting Help

Feel free to report GitHub issues or to contact us at: