🌬 Vento

Vento is the Galician word for wind but also a new template engine for Deno. It's inspired by other engines, such as Nunjucks, Liquid, Eta, and Mustache.

Why another template engine?

All these template engines mentioned above are great but they also have some drawbacks and none of them meets all my requirements, so I've created Vento.


  • It's not well maintained. The last version was released in Jun 2022. And the previous version in 2020.
  • It's not async-friendly. For example, you have some tags to work with sync values (like for and if) and others for async values (like asyncEach and ifAsync). Some features don't work in async contexts.
  • To me, it's very uncomfortable to have to type the delimiters {% and %} all the time (especially the % character).
  • By default, all variables are escaped, so you have to remember to use the safe filter everywhere. This is not very convenient for my use case (static site generators), where I can control all the content and the HTML generated.


  • It's not possible to invoke functions in a liquid template. For example {{ date.format("YY-mm-dd") }} fails.
  • It has the same problem as Nunjucks with the % character in the delimiters.


  • It has the same problem with the % character. And I don't like the opening and closing delimiters (<% and %>).
  • I like it can run javascript, but it's very inconvenient to do a simple forEach or if.


  • Perhaps too simple and the syntax can be a bit confusing.
  • Partials. It's not easy to include them dynamically.
  • The data context is a bit confusing to me.
  • Very uncomfortable to work with filters.

Vento syntax

First, let's take a look to the following example:

  {{ if printName }}
  <h1>{{ (await getUser(34)).name |> toUpperCase }}</h1>
  {{ /if }}
  • Everything is between {{ and }} tags. Unlike Nunjucks or Liquid, there's no distinction between tags {% tag %} and printing variables {{ var }}.
  • Vento, like Eta/EJS synstax, allows to use JavaScript code inside the tags. For example (await getUser(34)).name is real JavaScript executed at runtime.
  • Like Nunjucks, Liquid or Mustache, there are some specific tags like if for common things like conditions, loops, etc. The closed tag is done by prepending the / character (like Mustache).
  • It's async friendly, you can use await everywhere.
  • Filters are applied using the pipeline operator.