Finding needles in a haystack: Leveraging co-change dependencies to recommend refactorings.

•A refactoring recommendation tool using fine-grained co-change dependencies is proposed.•The approach outperforms a state-of-the-art approach based on quality metrics.•The approach’s refactorings complement the ones from other tools.•The refactorings from the approach are feasible and may spot further design problems.•Refactoring tools that challenge the software design may face strong resistance.