Apace with is a phrase that means something is happening at the same speed as something else. If you're looking for synonyms for this phrase, there are a few options to choose from. "In step with" is a common alternative, as it refers to being in sync with something else. "Side by side with" is another phrase that conveys a similar level of alignment. "Parallel to" is a more precise synonym, as it indicates something is happening at the exact same pace. Additionally, "synchronized with" is a term that can be used to describe apace with, as it refers to two or more things moving together in perfect tempo.