When comparing JsRender vs Nunjucks, the Slant community recommends Nunjucks for most people. In the question“What are the best JavaScript templating engines?” Nunjucks is ranked 5th while JsRender is ranked 24th.
Ranked in these QuestionsQuestion Ranking
Pros
Pro Clean syntax
JsRender's syntax is clean and intuitive. It's very similar to Handlebars with a lot of curly braces ({}).
Pro Very user friendly
Pro Building blocks for CMS Websites
Another token based system with all of the logic, looping and variable control that other engines provide. But in addition it supports some more advanced page composition elements e.g. block inheritance, includes, layout inheritance, custom tags and macros — all absolutely perfect for a CMS where pages are typically composed of a series of “building blocks”.
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Pro Suppported by Mozilla
Pro Has Jinja2 as role model
Pro Open Source
Cons
Con Lack of Documentation
The docs aren't updated and don't contain all the available functions that one could use.