I Pitted Gemini CLI Against Claude Code to Create Flappy Bird

1 kstonekuan 4 6/27/2025, 4:12:08 PM github.com ↗
I was curious to compare the new Gemini CLI with the new incumbent Claude Code, so I prompted both to create a Flappy Bird game from scratch.

Claude Code - took just one prompt - nice UI styling - high cost, ~$4, with opus 4

Gemini CLI - FREE - lots of fixes needed after first build - auto switched from 2.5 pro to 2.5 flash midway due to "slow response"

You can find all the code generated on GitHub: https://github.com/kstonekuan/gemini-v-claude-flappy-bird

I'd love to hear your thoughts and feedback!

Comments (4)

kstonekuan · 3h ago
Deployed both games to github pages here: https://kstonekuan.github.io/gemini-v-claude-flappy-bird/
Oras · 4h ago
I tried a simple prompt on both sonnet 4 and Gemini 2.5 pro (in cursor). Sonnet is a clear winner in quality.

The other limitation you mentioned (switching models) is due to its beta release, its free for now so not a fair comparison

kstonekuan · 3h ago
Cool to hear you had a similar experience, it did switch models after the initial build while I was fixing it, so it is still fair to say it was not able to one-shot the game like claude code
bitpush · 3h ago
How do we know if one or both models are not optimizing for this very same prompt?