Show HN: I built a text-based business simulator to replace video courses
Core_Dev Friday, January 16, 2026I am a solo developer, and I built Core MBA because I was frustrated with the "video course" default in business education.
I wanted to build a "compiler for business logic"—a tool where I could read a concept in 5 minutes and immediately test it in a hostile environment to see if my strategy actually compiles or throws a runtime error.
The project is a business simulator built on React 19 and TypeScript.
The core technical innovation isn't just using AI; it's the architecture of a closed loop between a deterministic economic engine and a generative AI validation layer.
The biggest technical hurdle was building the Market Engine.
I needed it to be mathematically rigorous, not a hallucinating chatbot. I wrote a custom `useMarketEngine.ts` hook that runs a discrete-event simulation. Every "run cycle," it solves a system of equations, including a specific Ad Fatigue formula—`1 / (1 + (power - 1) * fatigueFactor)`—to force diminishing returns.
I also coded the "Theory of Constraints" directly into the state management: the system enforces bottlenecks between Inventory, Demand, and Capacity. For instance, a single employee has a hard cap of 7 operations per day. If you scale demand beyond that without hiring, the system burns your cash on lost orders.
To handle the educational content, I moved away from hardcoded quizzes.
I built a module that pipes the static lesson text into Gemini Flash to generate unique "Combat Cases" on the fly. The AI validates your strategy against the specific principles of the lesson (like LTV/CAC) rather than generic business advice.
These two engines are connected by a "Liquidity Loop."
Passing the AI cases earns you virtual capital ($500), which is the only fuel for the Market Engine. You literally cannot play the game if you don't learn the theory.
If you go bankrupt, my heuristic `Advisor` analyzes your crash data—comparing `lostRevenue` vs `lostCapacity`—and links you back to the exact lesson you ignored.
I am inviting you to test the full loop: read a brief, pass the AI simulation (Combat Cases ), and try to survive in the Market Engine.
I specifically need feedback on: 1. The Content: I aimed for maximum density—are the lessons too dry? 2. The AI Simulation: Does it accurately validate your logic based on the lesson? 3. The Market Economy: Does the math feel balanced, or is the "Ad Fatigue" too punishing?