@Override
    public void appendInt(int value) {
      int offset = (int) (this.writeOffset & slabMask);
      getSlabForWrite().putInt(offset, value);
      this.writeOffset += Integer.BYTES;
    }
Returns the slab that the next value should be written to.
planetiler-core/src/main/java/com/onthegomap/planetiler/collection/AppendStoreRam.java