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Nunjucks

Seems like a quite good engine with a lot of possibilities to create functions and other logic which would make the templates possibly quite autonomous and could therefore be easily re-used as provided (with the required logic inside) for client-side rendering.

https://mozilla.github.io/nunjucks/

Mustache

Nice, but probably to too simplistic as it doesn’t provide any real options to manipulate the data in the rendering (even for simply number formatting).

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