anchor.diff:    main :: IO ()
     main = do
       runTest "logConfigs" checkLogConfig
  +    runTest "topologyConfigs" checkTopology
       outpath <- getEnv "out"
       writeFile outpath "done"
   
  
positive.code:   checkLogConfig :: String -> IO LoggerConfig
    checkLogConfig path = do
      either throwM return =<< decodeFileEither path
  ''
  
negative.code: 
  runHaskell "yamlValidation" cardanoPkgs (ps: with ps; [
    cardano-sl-util
    cardano-sl-infra
    split
  ]) {
    logConfigs = [
  