Cell cycle control is one of the most fundamental and intricate systems in eukaryotic cells. At the heart of this process are members of the cyclin-dependent protein kinase (Cdk) family, which are organized in an elaborate network to ensure the proper sequence of cell cycle events. While a strong focus has been placed on dissecting the molecular details of the complex regulation of cell proliferation, alternative approaches that rely on simplifying the cell cycle circuit in vivo have begun to provide new perspectives into this essential process. Using such a strategy in the fission yeast Schizosaccharomyces pombe, we recently demonstrated that the core cell cycle machinery acts as a quantitative platform for coordinating cell cycle progression and periodic transcription. This led us to design a novel synthetic cell cycle system that can be artificially controlled with unprecedented temporal resolution to understand how Cdk activity dynamics shape eukaryotic cell proliferation.