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Fintech

Card Reward Optimizer

Tells you which card to use at checkout for the best rewards.

Intermediate12h1–2 people17/20 fit
TL;DR

Build Card Reward Optimizer for people with several credit or debit cards in ~12h with 1–2 people. Stack: Next.js + Postgres + LLM.

Why it wins: Instant, tangible savings.

Build flow

01 · Problem
People leave rewards unused because card rules are confusing.
02 · Solution
Store each card's reward rules, detect the merchant category and recommend the best card with expected value and monthly caps.
03 · Build
  1. 1Model reward rules
  2. 2Map merchant categories
  3. 3Compute value
  4. 4Track caps
04 · Demo
Search 'grocery store' and see the best card and why.

MVP checklist

  • Rule library
  • Merchant lookup
  • Cap tracking
  • Monthly report

Tech stack

TechRole
Next.jsFrontend + API routes
PostgresRelational database
LLMLanguage model

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