A brief example of how we can replicate the principle of polymorphism.

polymorphism.go

package polymorphism

// Developer struct
type Developer struct {
	Fuel         string
	CanImplement bool
}

// Interface to add collection of methods
type Tasks interface {
	Bugfix()
	Improvement()
}

// Function using interface type in function parameter to get
// access to multiple methods via one interface similar
// to polymorphism
func SolveBugs(t Tasks) {
	t.Bugfix()
	t.Improvement()
}

// Method 1
func (d Developer) Bugfix() string {
	if d.Fuel == "Coffee" {
		return "Please solve the assigned bugs by EOD!"
	}
}

// Method 2
func (d Developer) Improvement() string {
	if d.CanImplement {
		return "How many days it will take to implement this feature?"
	}
}

func main() {
	d := Developer{Fuel: "Coffee", CanImplement: false}
	SolveBugs(d)
}