Abstract: Embryonic development requires precise timing and spatial organization, despite molecular noise and physical constraints. In this talk, I will explore how energy dissipation, spatial coupling, and mechanical cues shape the developmental accuracy, utilizing "bottom-up" synthetic and ex vivo models. I will first discuss energy-precision trade-offs in mitotic oscillators revealed by systematic ATP tuning in droplet-based artificial cells and how mitotic waves facilitate information transfer across a large space. Shifting to the role of mechanics, I will present findings on how substrate rigidity acts as a mechanoswitch for the zebrafish segmentation clock and how zebrafish blastomere aggregates, or pescoids, demonstrate "active wetting" physics, where contractility and mesendoderm induction drive spontaneous fluid-to-solid transitions, coupling mechanics to fate patterning. Together, these findings highlight energy and mechanics as fundamental regulators of developmental clocks essential for robust embryo development.