alt Hacker Newsi filed my swiss taxes for 2025 in 2026 (april) by dumping everything (local tax law, tax guide, my and my wife's documents, bank statements, income statements, etc.) into a folder and asking claude to fill it out. i had nothing to fix. submitted it.
I'm not specifically familiar with swiss tax law but european taxes are typically far more simple than american taxes.
I have a relatively straightforward tax return and still found significant mistakes on 3 out of the last 4 years of returns filed by CPAs.