When comparing Harp vs Middleman, the Slant community recommends Middleman for most people. In the question“What are the best static site generators?” Middleman is ranked 7th while Harp is ranked 29th. The most important reason people chose Middleman is:
[Minification and compression](http://middlemanapp.com/advanced/file-size-optimization/index.html) are as easy as setting a few configuration options, and [unique asset hashes](http://middlemanapp.com/advanced/improving-cacheability/) are available to allow you to invalidate the cache of files that change regularly.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Compiles assets on request
Rather than regenerate the whole site when a file changes, Harp only reloads what is necessary, keeping the compile time fast.
Pro Supports popular languages
Harp supports a large variety of languages, including Jade, CoffeeScript, Stylus and Sass. See the full list here.
Pro Built in minification, compression, and cache busting
Minification and compression are as easy as setting a few configuration options, and unique asset hashes are available to allow you to invalidate the cache of files that change regularly.
Pro Support for a variety of templating languages and preprocessors
Middleman supports lots of compiled languages, such as Less, Markdown, Textile, CoffeeScript, Stylus and more.
Pro Extensible and flexible
Middleman has a resources page full of official and community extensions.
Pro External pipeline management with Webpack
Replace your Gulp, Grunt, Bower configs
Pro Embraces Rails conventions
Middleman follows established conventions so if you know rails, you can easily pick up middleman.
Pro Easy deployment options
Cons
Con Limited extensibility
There are no plugins available to extend the functionality or language support of Harp.
Con Too much magic happens
For new users it is hard to understand what is going on and why.
Con A little more complicated than other static site generators
Middleman is a big piece of software, it's not simply a static blog generator. Because of all the functionality and flexibility it offers it can be a little more complex than other static site generators and a little harder to learn all of its bells and whistles.