The Universe started without the heavy elements that make the complexity of our surrounding world (e.g. carbon, oxygen). In this talk, I will showcase ground-breaking advances in the numerical modelling of how these chemical elements are produced in stars, how they are dispersed around young galaxies by energetic events, and how they get ionized to power the emission and absorption lines we observe in the spectra of distant objects. Leveraging these new prediction capabilities will take us from interpreting the highest-redshift emission lines observable by JWST to the most local chemical abundances of Galactic stars, shedding a new light on how metal-poor stars enriched the Universe in the process.