static Map<Pair<S, Int>, BufferedImage> keriyo_resized_cache = syncExpiringMap(3600.0);

static BufferedImage keriyo_resized_cached(S code, int width) {
  BufferedImage img = keriyo_resized_cache.get(pair(code, width));
  if (img == null) mapPut(keriyo_resized_cache, pair(code, width),
    img = resizeImage(keriyo(code), width));
  ret img;
}

Began life as a copy of #1020233