unrecognized import path (import path does not begin with hostname)

go get downloads dependencies and packages by assuming that the import path (in the import statements in source code) identifies a URL where the package can be downloaded, e.g. github.com/habeanf/yap. It works so long as developers use imports correctly; unfortunately, the developer of the yap project did not.

Where they import yap/app, they should be importing github.com/habeanf/yap/app, etc. The only fix would be to clone the GitHub repo into $GOPATH/src/yap manually and then try to build it. You might want to open a GitHub issue on that project and request that they fix the import paths so it can be built like a normal Go project.