1. `ninja`
2. `ninja check-functional`
3. Running `./src/bitcoind -regtest`, and then `./src/bitcoind -datadir=/tmp/regtest -regtest -listen=0 -server=0` results in: `Error: Chronik failed binding to 127.0.0.1:18442: error creating server listener: Address already in use (os error 48)`
Or in a similar OS error.