persistable sclass MultiPullbackJuicer extends StopLossJuicer {
  sclass Level {
    // Starting at juice value minJuiceValue, keep keepPercentage of the juice
    settable double minJuiceValue;
    settable double keepPercentage;
  }
  
  settableWithVar new L<Level> levels;
  
  // Highest juice value seen
  settableWithVar double crest = -infinity();
  
  {
    onCalculatingCloseSignals(signals -> {
      if (juiceValue > crest)
        crest(juiceValue);
        
      if (crest < 0) ret;
      
      double keepPercentage = getKeepPercentageForJuiceValue(juiceValue);
      if (isNaN(keepPercentage))
        ret;
        
      double toKeep = crest*keepPercentage;
      double maxPullback = crest-toKeep;

      var signal = new CloseSignal().createdBy(this).reason("Profit");
      if (maxPullback == 0)
        signal.strength(1);
      else
        signal.strength(doubleRatio(crest-juiceValue, maxPullback));
      signals.add(signal);
    });
  }
  
  double getKeepPercentageForJuiceValue(double juice) {
    for (int i = l(levels)-1; i >= 0; i--) {
      Level level = levels.get(i);
      if (juice < level.minJuiceValue)
        continue;
        
      Level nextLevel = get(levels, i+1);
      if (nextLevel == null)
        ret level.keepPercentage;
      
      ret blend(level.keepPercentage, nextLevel.keepPercentage,
        transformToZeroToOne(juice, level.minJuiceValue, nextLevel.minJuiceValue));
    }
  }
}