Building a Full App with Lovable + Claude + Gemini: A Case Study
A software engineer with no fullstack/frontend experience built Earnest — a free app that helps users track bank account bonuses (open account, meet requirements, collect bonus, close it, repeat). The stack combined Lovable, Claude, and Gemini to produce a working product with over 100 real users.
Stack & Surprising Findings
- Lovable handled UI and scaffolding — got the developer from zero to a real app "embarrassingly fast."
- Claude was far better at understanding intent when the full user flow was described instead of individual features.
- Gemini served as a useful second opinion when the developer was stuck.
- The hardest part wasn't the AI itself — it was knowing what to ask for.
Results
- 19+ active promotions tracked
- $9,700+ in available bonuses tracked
- 100+ real users
- $5,000+ in bonuses earned by users so far
The app is live at earnest.lovable.app. The developer is open to sharing more about specific prompts that worked, what failed completely, and how they debugged without being able to read the code properly.
📖 Read the full source: r/ClaudeAI
👀 See Also
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Developer Ships Steam Game with Claude Code: Lessons on Vibe Coding vs. Vibe Engineering
A developer shipped Codex Mortis, a necromancy-themed bullet hell game on Steam, using Claude Code for AI-assisted development. The project required two complete rewrites after the initial prototype, highlighting the gap between prototype and production.