I needed weekly performance reports emailed to clients. Each report had four charts: revenue trend, conversion rate, top products, traffic sources. The app was Python. The charts on the live dashboard were Chart.js because that's what the frontend team had standardised on, and they looked good. First attempt was matplotlib. It produced charts. They looked like matplotlib charts, which is to say fine for a scientific paper and terrible for a client email that's supposed to match the product's visual language. The brand colours were approximate. The fonts were wrong. The legend looked like it was from 2008. Clients politely asked why the emailed reports didn't match the dashboard. Second attempt was  chartjs-node-canvas . This works by running Chart.js against a Node canvas polyfill. Close to the real thing, but not identical. Gradients rendered differently. Some plugins didn't work at all. And now I was running a Node service from Python for one specific job, which felt wrong.…