After building five products across different tech stacks, I have strong opinions on what a solo founder or small team should default to. Fewer choices, more output.
Backend: Laravel. Nothing comes close for a solo developer building web applications.
Frontend: Vue.js with Inertia. If you need a mobile app, Flutter.
Database: PostgreSQL. MySQL is fine, but PostgreSQL handles JSON, full-text search, and complex queries better.
The pattern is simple: pick boring, proven tools and master them deeply.