I think foreground indexing is the right default: it's confusing for bin/search index to exit successfully but not have actually rebuilt indexes, and it makes analyzing or debugging indexing issues more difficult. If there is an actual bug, this may queue a large number of immediately-fataling tasks.

I'd rather address this in other ways, like:

• call out --background in the documentation; or
• use a progress bar instead of printing out a line per object, and call out --background in the preamble.

In D9362#6, @epriestley wrote:

I think foreground indexing is the right default: it's confusing for bin/search index to exit successfully but not have actually rebuilt indexes, and it makes analyzing or debugging indexing issues more difficult. If there is an actual bug, this may queue a large number of immediately-fataling tasks.

I'd rather address this in other ways, like:

• call out --background in the documentation; or
• use a progress bar instead of printing out a line per object, and call out --background in the preamble.

Sounds reasonable to me. Let me try to come up with something.