constant-sum automated market maker

proof-of-concept of a constant-sum AMM, aka a liquidity pool where the relation between its assets is determined by the following invariant:

x + y = k

Run unit/integration tests

yarn install
yarn test

Run Echidna fuzzing tests

docker pull trailofbits/eth-security-toolbox
docker run -it -v "$PWD":/home/training trailofbits/eth-security-toolbox
solc-select 0.8.10
cd /home/training
echidna-test . --contract EchidnaCSAmm --config config.yaml