We use this expression to say that things have been successful until now and you hope that they will continue to be successful, but you know that the task, etc. is not finished yet.
You can use this phrase in ………… language.
A: How’s your new job going?
B: So far, so good. I have to work hard, but the people are good.
A: How’s the meeting so far?
B: So far, so good – but nothing has been signed yet.