https://stackoverflow.com/questions/52079662/go-get-cannot-find-local-packages-when-using-multiple-modules-in-a-repo

api/contracts/contract.go

  
package contracts  
  
import (  
 "math/big"  
 "strings"  
)....  
  
func DeployContract(...)  

api/contract.go

  
package main  
  
import (  
 "api/contracts"  
...)  
  
func deployContract(c echo.Context) error {  
         address, tx, token, err := contracts.DeployContract(auth, client)  
...  
}  

! Best Import is api/go.mod

  
module api  
  
require (  
         api/contracts v0.0.0  
...)  
  
replace (  
         api/contracts v0.0.0 => ./contracts  
...)  

And api/contracts/go.mod

  
module api/contracts  
  
require (  
...)  

``` ` `` ``````