Extremely slow performance

[HACKERALERT]

Hi, I love this library but I'm experiencing some very slow speeds of 2 MB/s encode and 0.05 MB/s decode. Am I doing something wrong? Here's my usage of infectious which operates on byte slices.

// Reed-Solomon encoder
func rsEncode(rs *infectious.FEC,data []byte) []byte{
	var res []byte
	rs.Encode(data,func(s infectious.Share){
		res = append(res,s.DeepCopy().Data[0])
	})
	return res
}

// Reed-Solomon decoder
func rsDecode(rs *infectious.FEC,data []byte) ([]byte,error){
	tmp := make([]infectious.Share,rs.Total())
	for i:=0;i<rs.Total();i++{
		tmp[i] = infectious.Share{
			Number:i,
			Data:[]byte{data[i]},
		}
	}
	res,err := rs.Decode(nil,tmp)
	if err!=nil{
		return data[:rs.Total()/3],err
	}
	return res,nil
}

Even a pure Python implementation I used is faster than this, so I must be doing something wrong. But I've read the docs multiple times and haven't been able to come up with a solution. Would you mind taking a quick look? Thank you very much!