Ayush Newatia's mentorship principles from the Rails World website project: (1) don't write any of the code yourself — lay out guidance in writing and use code review / pair programming; (2) deflect all credit to the junior and absorb any blame, even though the external upside is limited; (3) let the junior's constraints strip complexity you would otherwise add — Newatia would never have skipped an esbuild pipeline and used plain custom elements if he had been building it himself. The mentor often learns more than the student.