Harshavardhan Lingampally

Can GPT-OSS-20B Create a Bill-Splitting App?

August 21, 2025

I'm exploring whether GPT-OSS-20B can create a production-grade bill-splitting app without me writing code.

Rules

  1. I cannot spend more money than I currently do. At the moment, I have a ChatGPT Plus subscription and a custom PC build with a Quadro RTX 6000.
  2. I am not allowed to write a single line of code.

Approach

To achieve this, I’ll use GPT-5-level thinking to craft detailed GitHub issues and constrain the open-source model to work solely based on the repository's content.

Setup: OpenCode connected to GPT-OSS-20B, running on LMStudio through my custom PC.

Good luck, GPT-OSS-20B!