Not sure if this is what you're after but you can call PushOutput on your TemplateContext to redirect the output to your own implementation of IScriptOutput using a TextWriter or anything really. Another area to investigate on the template context there is to override the Write method which also may provide you with some hooks to achieve what your looking for.

Thanks for the reply. I tried checking it, but for me it looks like the string conversion is done before passing outout to Output. I might have mistaken, but I couldn’t figure out how to do that without conversion to string. There seems to be some assumptions that the output is string. Write could be something to investigate.

You have to derive from TemplateContext and overrides the methods that fits what you are looking for. Evaluation and conversion to string is operated from there e.g:

This is for example what was done in the kalk project that is using Scriban under the hood:

https://github.com/xoofx/kalk/blob/dfb1939689ed9db73f202ac43c63babff6623368/src/Kalk.Core/KalkEngine.cs#L347-L358

Thanks a lot, I'll try that one and report back!