When talking about a year in the past, do you use by, in or before?

There has been a few questions on this but this one example has never really been answered. If you were writing a report on the year before and you wanted to say that the a project was completed in that year, would you say:

1. In 2018, the Genesis project was successfully completed
2. By 2018, the Genesis project was successfully completed

The meaning I want to convey is that during 2018, the project was completed, not before.

Thanks

Solution 1:

The meaning I want to convey is that during 2018, the project was completed, not before.

Then you should use

In 2018, the Genesis project was successfully completed.

It was completed in that year and not before.

By 2018, the Genesis project was successfully completed.

[could mean] it was completed by the end of 2017 and possibly even years before.