I'm not sure if I'm missing something but I'm not able to use Golang's standard libraries (fmt, strconv, etc.) in the inline problem editor which makes doing things like converting int to string difficult. Additionally, I can't print to stdout, etc. I do see fmt being used in the solution. Basically, this forced me to do some weird stuff like converting strings to bytes to avoid costly string concatenation.

```go
type Solution struct{}

// type Stack struct {
//  items []interface{}
// }

// func NewStack() Stack {
//  return Stack{}
// }

// func (s *Stack) Empty() bool {
//  return len(s.items) == 0
// }

// func (s *Stack) Push(item interface{}) {
//  s.items = append(s.items, item)
// }

// func (s *Stack) Pop() (interface{}, error) {
//  if s.Empty() {
//    return nil, errors.New("stack is empty")
//  }

//  item := s.items[len(s.items)-1]
//  s.items = s.items[:len(s.items)-1]
//  return item, nil
// }

// func (s *Stack) Top() (interface{}, error) {
//  if s.Empty() {
//    return nil, errors.New("stack is empty")
//  }

//  return s.items[len(s.items)-1], nil
// }

func (s *Stack) Size() int {
  return len(s.items)
} 

func (s *Solution) decimalToBinary(num int) string {
  if num == 0 {
    return "0"
  }
  stack := NewStack()
  for num > 0 {
    remainder := "0"
    if num%2 == 1 {
      remainder = "1"
    }
    stack.Push([]byte(remainder)[0])
    num /= 2
  }
  var binary []byte = make([]byte, stack.Size())
  for i, n := 0, stack.Size(); i < n; i++ {
    val, _ := stack.Pop()
    binary[i] = val.(byte)
  }
  return string(binary)
}