The spin-dynamics kernel running in Pyodide. Every calculation goes to a web worker, so the page stays responsive.
Ctrl+Enter runs. show_spectrum, show_fid and show_image draw on the right. The 12800-orientation powder is the slow one, about a minute. The 1600-point powder and magic-angle spinning take a few seconds. Grid names such as leb_2ang_rank_17 are loaded from src/spynach/grids.
The spectrum will land here.