go mod unable to find modules

I'm trying to build a Docker image using a go compiled binary as the ENTRYPOINT but I'm unable to compile the binary because the go mod is unable to find one of the required files.

the project structure looks like this:

editor/
├── container
│   ├── Dockerfile
│   └── src
│       ├── install-browsers.sh
│       ├── selenium-server-standalone-3.141.59.jar
│       └── webCopy
│           ├── go.mod
│           ├── go.sum
│           └── main.go
├── copier
│   ├── copier.go
│   ├── internal
│   │   └── utils.go
│   └── scripts
│       └── load.go
└── resource
    └── handler.go

The file I'm trying to compile is webCopy/main.go
Inside that file I need to import the module editor/copier

The path to the editor module is:
bitbucket.org/backend/editor
which is inside the GOPATH

The error the go mod tidy gives me is:

go: finding module for package bitbucket.org/mvps/backend/editor/copier
bitbucket.org/backend/editor/container/src/webCopy imports
        bitbucket.org/backend/editor/copier: cannot find module providing package bitbucket.org/mvps/backend/editor/copier: reading https://api.bitbucket.org/2.0/repositories/mvps/backend?fields=scm: 404 Not Found

I really don't want to mix the copier module inside the src of the container, the reason being I feel the submodules to the main should be separated, yet inside the editor module.

Furthermore, I'm using go.mod as a way to get a clean image by compiling main.go and using the binary to create a new clean artifact, so I would like to have the go.mod and go.sum files inside editor/container/src/webCopy/

btw. I have checked the package names and everything is properly named.

FYI if you are using a go modules build - you are no longer using GOPATH - so that is not the issue.

If you want a custom build - and not have to create laborious git key access to repo's from within a docker build - you can leverage the replace directive in go.mod

So add to .../webCopy/go.mod the following line:

replace bitbucket.org/backend/editor/copier => ../../../copier/

this will instruct the go build to use this relative path (instead of a direct https download)