build error: net/smtp module reports undefined: tls.Conn

[everyx]

❯ tinygo run verifier.go 
# net/smtp
/usr/lib/go/src/net/smtp/smtp.go:72:24: undefined: tls.Conn
/usr/lib/go/src/net/smtp/smtp.go:172:25: undefined: tls.Conn

verifier.go

package main

import (
	"encoding/json"
	"fmt"

	emailVerifier "github.com/AfterShip/email-verifier"
)

type Result struct {
	Data  *emailVerifier.Result `json:"data"`
	Error error                 `json:"error"`
}

func (p Result) ToJson(result Result) (*string, error) {
	bytes, err := json.Marshal(result)

	if err != nil {
		fmt.Println("Error converting to JSON:", err)
		return nil, err
	}

	json := string(bytes)

	return &json, nil
}

//export add
func verify(email string) string {
	var result Result

	verifier := emailVerifier.NewVerifier().EnableAutoUpdateDisposable()

	ret, err := verifier.Verify(email)
	if err != nil {
		result = Result{
			Data:  nil,
			Error: err,
		}
	} else {
		result = Result{
			Data:  ret,
			Error: nil,
		}
	}

	bytes, err := json.Marshal(result)
	if err != nil {
		fmt.Println("Error converting to JSON:", err)
		return fmt.Sprintf("{error:%s}", err.Error())
	}

	return string(bytes)
}

func main() {
	fmt.Println(verify("[email protected]"))
}