Nanoc vs Metalsmith

Nanoc is a good choice if you need to support a site with a more complex structure than a simple blog. Nanoc is more agnostic to the types of pages you have, and allows you to do finer tuned refinements like customizing the URL structure.

Nanoc has a modular architecture which makes it easier to incorporate plugins and functionality from other projects as well as extend functionality.

Nanoc takes multilingual sites into consideration and has features to make translations easier to implement.

Nanoc has a check command to run tests against your site and make sure it meets requirements you define.

There are built in checks to validate HTML and CSS, as well as validating internal and external links.

Nanoc is friendly with different CSS and HTML preprocessors, so you can easily use SASS, LESS, HAML, Markdown and more.

Because metalsmith is at its core focused on transforming directories of files, it can be used for more than just static site generation, and could be used as a build tool, a documentation generator, or any use that requires file transformations.

Everything in metalsmith is a plugin, and it is designed to make it easy to write new ones.

Metalsmith uses a chaining API that's consistent and simple to use:

Metalsmith(__dirname)
  .use(markdown)
  .use(templates('handlebars'))
  .build();