How I Built a Financial Dashboard for Startups

I'm a solo founder building culta.ai - a financial management platform that helps early-stage founders track budgets, burn rate, and cash flow without needing an accountant. Here's a quick look at the stack and a few things I learned along the way. The Stack Next.js 15 (App Router) + React 19 Prisma + PostgreSQL Stripe for billing and Connect NextAuth for authentication Tailwind CSS for styling Deployed on Railway Multi-Entity Architecture One thing I needed early was support for multiple businesses per user. A freelancer might have a consultancy and a side project, they shouldn't need two accounts. Every dashboard query is scoped to the selected entity using a React context provider. Switching between businesses is instant, no page reload. Free Financial Calculators as a Growth Channel Instead of just blogging, I built 17 interactive calculators - burn rate, runway, SaaS pricing, unit economics, and more. Each one is its own page, targets a specific keyword, and funnels users toward s