如何使用Now（zeit.co）在golang中使用本地文件？

I'm creating an api with golang and zeit-now. I want the API to return a password generated from a list of words (30k). Everything works if I use a local server (http.ListenAndServe), but when I try to access the concerned endpoint with the now link, an error occurs.

I tried to use the config.includeFiles option, but it doesn't work. I also tried to use local path, absolute path but nothing is working.

Here is the now.json and randDict.go files:

now.json

"builds": [
            {
                "src": "/lambdas/randDict/randDict.go",
                "use": "@now/go",
                "config": {
                    "includeFiles": [
                        "template/wordsGist"
                    ]
                }
            }
]

randDict.go

// Create a slice with the words from the words' file
func createWordsSlice() ([]string, int, error) {
    // Read all the words inside the file "wordsGist"
    file, err := ioutil.ReadFile("template/wordsGist")
    if err != nil {
        fmt.Println(err)
        return nil, 0, err
    }
    // Split the words into a slice
    words := strings.Split(string(file), "
")
    return words, len(words), nil

}

Here I expect a slice with all the words, which I'll be using later for password generation, but I get an error and a empty slice (nil).

Here is the github if you want to read all the code.