A mini app is not a website opened inside Telegram. It's a separate kind of product with its own rules: no address bar, no tabs, no patience for loading. If the first screen stalls, there is no second screen — the person closes the window and goes back to the chat.
So I don't start with design. I start by asking which single action the person opens the app for. Everything else is built around it, and extra screens get cut before anyone writes them. The project ends up smaller, cheaper and shipping sooner.
A model speeds the build up. The routine — standard screens, plumbing, migrations, tests — it writes faster than I do, and that saves the project weeks. The decisions stay mine: what we build, how it works inside, where the security boundaries are and what actually ships. Code I did not understand does not go into the project.
After that it's ordinary engineering with no magic: typed code, validation of everything from outside, database migrations instead of manual edits, tests on the money paths, and a compose file that brings the whole thing up with one command on any machine.