SKALE Consensus: a Blockchain Consensus engine in C++

SKALE Consensus is an ultra-high-performance blockchain consensus engine written in C++.

Key Features of SKALE Consensus

• Over 10,000 TPS
• Byzantine fault tolerant — no block gaps, and stable performance even with up to 1/3 of nodes offline
• Provably secure
• Forkless
• Single-block finality — blocks are immediately finalized upon commitment
• Resilient to arbitrarily long network disruptions and delays through an asynchronous network model
• Multiple block proposers per block — ensures protocol stability even when some proposers are offline
• Secure against MEV and front-running — provably resistant to manipulation

Read the spec for more exciting features https://docs.skale.network/technology/consensus-spec

See visualization of live conseneus https://www.youtube.com/watch?v=0NGCSRjjPkk

Building from Source

The preferred build and execution environment is Ubuntu 22.04.

Later versions of Ubuntu may work, but they are not officially tested.

1. Install packages

sudo add-apt-repository ppa:ubuntu-toolchain-r/test
sudo apt update
sudo apt install -yq libprocps-dev gcc-11 g++-11 valgrind gawk sed libffi-dev ccache \
    libgoogle-perftools-dev yasm texinfo autotools-dev automake \
    python3 python3-pip cmake libtool build-essential pkg-config autoconf wget \
    git libargtable2-dev libmicrohttpd-dev libhiredis-dev redis-server openssl \
    libssl-dev doxygen libgcrypt20-dev

2. Clone the repo

git clone --recurse-submodules https://github.com/skalenetwork/skale-consensus.git

3. Build dependencies in debug mode

cd skale-consensus/deps && ./build.sh DEBUG=1

4. Configure the CMake build in Debug M ode.

cd .. && cmake . -Bbuild -DCMAKE_BUILD_TYPE=Debug

5. Build All Targets Using All Available CPU Code

cmake --build build -- -j$(nproc) 

Running tests

After the build completes, the build directory contains a test binary named consensust,
which can run a number of consensus tests.

The test subdirectories are located in the tests directory.
To run a specific test, navigate to its corresponding subdirectory.

Examples:

To run one node

cd test/onenode
sudo NO_ULIMIT_CHECK=1 TEST_TIME_S=180 TEST_TRANSACTIONS_PER_BLOCK=10 ../../build/consensust [consensus-basic]  

Running SGX simulation test

You can run four and 16 nodes test using sgx simulation and test keys.

First install docker and docker compose, since the test runs sgxwallet in a docker container

sudo apt update
sudo apt install -y \
    ca-certificates \
    curl \
    gnupg \
    lsb-release
sudo mkdir -p /etc/apt/keyrings
curl -fsSL https://download.docker.com/linux/ubuntu/gpg | \
    sudo gpg --dearmor -o /etc/apt/keyrings/docker.gpg
echo \
  "deb [arch=$(dpkg --print-architecture) \
  signed-by=/etc/apt/keyrings/docker.gpg] \
  https://download.docker.com/linux/ubuntu \
  $(lsb_release -cs) stable" | \
  sudo tee /etc/apt/sources.list.d/docker.list > /dev/null
  sudo apt update
  sudo apt install -y docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin             

Now start sgx server in a docker container

cd run_sgx_test
sudo ./run.bash

Check that sgxwallet has successfully started (it takes several minutes)

You can check progress by doing

docker logs run_sgx_test-sgxwallet-1

When the sgxwallet is up and running, you will see the following message in the log

[2025-05-20 12:49:43.323] [info] Started ZMQ worker thread 14
[2025-05-20 12:49:43.323] [info] Starting ZMQ worker thread 15
[2025-05-20 12:49:43.323] [info] Started ZMQ worker thread 15
[2025-05-20 12:49:43.323] [info] Created thread pool
[2025-05-20 12:49:43.323] [info] Releasing SGX worker threads  ...
[2025-05-20 12:49:43.323] [info] Starting zmq server on port 1031 ...
Completed initAll.
[2025-05-20 12:49:43.323] [info] Released SGX worker threads.
[2025-05-20 12:49:43.323] [info] Inited zmq server.
Found test keys.
[2025-05-20 12:49:43.323] [info] ZMQ server socket created and bound.
[2025-05-20 12:49:43.323] [info] Started zmq read loop.

Now you can check that test keys are available by running the following command:

cd sgx_data
ls

You should see, in particular, the following files:

16node.json  
4node.json 

These files are config files for 4 and 16 nodes respectively used by the test.

Now you can run the test with 4 nodes or 16 nodes.

cd ../test/fournodes
sudo TEST_TIME_S=180 TEST_TRANSACTIONS_PER_BLOCK=10 ../../build/consensust [consensus-basic]

or

cd ../test/sixteennodes
sudo TEST_TIME_S=180 TEST_TRANSACTIONS_PER_BLOCK=10 ../../build/consensust [consensus-basic]

The test checks if the config files 4node.json and 16node.json are present, and runs the tests against the wallet. If the files are not present, the test runs in a mockup mode.

Contributing

If you have any questions please ask our development community on Discord.

License

Copyright (C) 2018-present SKALE Labs