So `html` isn't a view engine; valid options could be 'ejs' or 'jade'. Let's go with [ejs](http://embeddedjs.com) because it's easy. Do exactly what you thought should be done: add a dependency for `ejs`, then `require` it into your code. Looking over one of my projects, it seems that this should do the trick:

```
ejs = require('ejs');
...
app.engine('html', ejs); // use EJS to handle files with .html extension
app.set('view engine', 'ejs'); // use EJS as default view engine
```

Admittedly, the documentation around setting up view engines is a bit sparse on the Express website itself.