I just deployed 11ty using netlify yesterday.
In the frontend of the sample installation it says "3. Delete this message from _includes/base.njk."
base.njk is located in _includes/layouts/, though.

@nilsmielke Care to submit a PR? Source file is in the base blog repo:
https://github.com/11ty/eleventy-base-blog/blob/master/_includes/layouts/base.njk#L26
@DirtyF I'm not a very experienced GitHubber. Tried and seem to have don't the right things. Thanks for the encouragement. :)
Beautiful, thanks all!
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@nilsmielke Care to submit a PR? Source file is in the base blog repo:
https://github.com/11ty/eleventy-base-blog/blob/master/_includes/layouts/base.njk#L26