I Built a Production-Ready Indian Tax Calculator in ~1 Hour Using Claude Code — Here’s Why and How

Every April I go through the same thing. Tax declaration deadline shows up. I open my company's internal tax calculator. I enter my deductions — 80C, NPS, health insurance. I look at the tax payable. I change a deduction amount to see how it affects the number. Nothing changes. I change it again. Still nothing. The total tax payable just sits there, frozen, not reflecting what I just typed. I refresh. Enter everything again. Same thing. I don't know if it's a bug o