How to have "Go to definition" in VSCODE find functions defined in src folder of current environment?

I am developing a project with a stardard folder structure:
base/
base/Project.toml
base/src/
base/src/file.jl

When specify in vscode that I should use the environment defined with the base/Project.toml then I can “go to definition” of functions defined in packages added to that environment, but I can not go to definitions defined in base/src/file.jl

How can I make vscode aware of those functions?

Thanks in advanced :slight_smile:
Shane