Config does not seem to be read

[Zepp10x]

In my project, I have two folders where I put templates: ./templates/ and ./static/templates/.

.
├── brunch-config.js
├── node_modules
├── package.json
├── package-lock.json
├── public
├── static
│   ├── assets
│   ├── js
│   ├── scss
│   └── templates
└── templates

I would like nunjucks-brunch to only process the templates in ./static/templates/, therefore I configured it in the following way in ./brunch-config.js:

module.exports = {
  (…)
  plugins: {
    nunjucks: {
      templatePath: 'static/templates'
    }
  }
  (…)
}

Unfortunately, nunjucks-brunch will still pick up the templates in ./templates/. What am I doing wrong?