Output is buffered if evaluator is managed with systemd

[fonglh]

This makes it impossible to follow the logs and the timestamps are also affected.

Can be solved by placing STDOUT.sync = true at the top of the program.

[lowjoel]

Timestamps? Timestamps are set in Rails' logger, which is before buffering.

I think this should be an environment thing, it should not be enabled by default.

[fonglh]

The output doesn't have timestamps at all, so the timestamps come from systemd's logging.
Buffering behaves differently when run directly from the command line vs being run as a service.

I agree it probably shouldn't be enforced here, so if there's any other way to turn off the buffering I'm willing to try it.