Feature request: ability to opt-in to an assert build for nightlies

[DilumAluthge]

I think this probably only makes sense for nightlies.

[SaschaMann]

Should it be the default or should there be a separate version like nightly-assert?

[DilumAluthge]

Should it be the default or should there be a separate version like nightly-assert?

Definitely not the default.

[DilumAluthge]

It could be nice to make the API compatible with #88, so that I could both choose the commit and also use an assert build.

[SaschaMann]

An extra input would allow that.