code: public Packet putLong(long l, ByteOrder order) {
          var buffer = HEAP_BUFFER_POOL.take(Long.BYTES);
          var array = buffer.putLong(order == ByteOrder.LITTLE_ENDIAN ? Long.reverseBytes(l) : l).array();
          
          try {
              return enqueue(Arrays.copyOfRange(array, 0, Long.BYTES));
          } finally {
              HEAP_BUFFER_POOL.give(buffer);
          }
      }
docs: Writes a single {@code long} with the specified {@link ByteOrder} to this {@link Packet}'s payload.
  
  @param l     A {@code long}.
  @param order The internal byte order of the {@code long}.
  @return The {@link Packet} to allow for chained writes.