BinaryIndexedChronicleAppender's setConfig method is using generics (in AbstractChronicleAppender<C>.setConfig(C config)), which is affected by Java's type erasure [1][2][3]. To workaround this, override setConfig with the desired type.
public class BinaryIndexedChronicleAppender extends BinaryChronicleAppender<IndexedLogAppenderConfig> {
// ...
@Override
public void setConfig(IndexedLogAppenderConfig config) {