Using GPT Codex, DeepSeek V4 and Kimi K3 on a Real OSS Project

Development was done in OpenCode using:

• GPT Codex 5.3 • DeepSeek V4 • Kimi K3

Each model had noticeably different strengths.

I have used GPT Codex 5.3 to create architecture.

Kimi K3 for review and refactor

DeepSeek V4 for review and documentation

The total development cost was around $8 in model usage.