Build your own code reviewer and benchmark it against CodeRabbit
A developer built a code reviewer in a day and compared it with CodeRabbit: 96s per review, $0.05 per review and 73% of bugs found, versus 228s, $0.11-0.16 and 59% for CodeRabbit.
Source
@dunkedtoast on X · 2026-10-21
Written in our own words. Credit to the original author. Link checked 2026-10-23.
What they did
A developer built a code reviewer in a day and compared it with CodeRabbit: 96s per review, $0.05 per review and 73% of bugs found, versus 228s, $0.11-0.16 and 59% for CodeRabbit.
Result (as claimed)
On his test set the homemade reviewer was faster, cheaper and found more bugs.
Tools they used
Cost: Pricing depends on the tools you pick; check each official pricing page.
Set it up
Pick a contained repo or task
Start on a branch or side project where mistakes are cheap.
Install and configure
Set up AI coding agent. Read what it can run on your machine and limit permissions where possible.
Run it on a real task
Give it a well-scoped issue and let it work. Review the diff like any pull request.
Add guardrails
Keep tests and CI in the loop, and never let an agent push to main or touch production secrets unattended.
Copy the full setup prompt
Paste into your agent and it will walk you through the setup, asking before anything that sends, posts or spends.
You are helping me set up this AI use case end to end in Claude Code. Goal: Build your own code reviewer and benchmark it against CodeRabbit What the original author did: A developer built a code reviewer in a day and compared it with CodeRabbit: 96s per review, $0.05 per review and 73% of bugs found, versus 228s, $0.11-0.16 and 59% for CodeRabbit. Reported result (as claimed by the author): On his test set the homemade reviewer was faster, cheaper and found more bugs. Source: https://x.com/dunkedtoast/status/2112937911352168523 Tools they used: AI coding agent Category: Dev & ops Please: 1. Ask me 3 short questions about my situation (accounts I have, budget, what I want the output to look like). 2. Propose a step-by-step plan using these tools or cheaper alternatives, with the time and cost of each step. Use official pricing pages; say "check pricing" if unsure. 3. Then do the setup with me one step at a time, waiting for my OK before anything that sends messages, posts publicly, spends money or deletes data. 4. Finish with a checklist to run it again next time.
You are helping me set up this AI use case end to end in Codex. Goal: Build your own code reviewer and benchmark it against CodeRabbit What the original author did: A developer built a code reviewer in a day and compared it with CodeRabbit: 96s per review, $0.05 per review and 73% of bugs found, versus 228s, $0.11-0.16 and 59% for CodeRabbit. Reported result (as claimed by the author): On his test set the homemade reviewer was faster, cheaper and found more bugs. Source: https://x.com/dunkedtoast/status/2112937911352168523 Tools they used: AI coding agent Category: Dev & ops Please: 1. Ask me 3 short questions about my situation (accounts I have, budget, what I want the output to look like). 2. Propose a step-by-step plan using these tools or cheaper alternatives, with the time and cost of each step. Use official pricing pages; say "check pricing" if unsure. 3. Then do the setup with me one step at a time, waiting for my OK before anything that sends messages, posts publicly, spends money or deletes data. 4. Finish with a checklist to run it again next time.
You are helping me set up this AI use case end to end in Grok Bot. Goal: Build your own code reviewer and benchmark it against CodeRabbit What the original author did: A developer built a code reviewer in a day and compared it with CodeRabbit: 96s per review, $0.05 per review and 73% of bugs found, versus 228s, $0.11-0.16 and 59% for CodeRabbit. Reported result (as claimed by the author): On his test set the homemade reviewer was faster, cheaper and found more bugs. Source: https://x.com/dunkedtoast/status/2112937911352168523 Tools they used: AI coding agent Category: Dev & ops Please: 1. Ask me 3 short questions about my situation (accounts I have, budget, what I want the output to look like). 2. Propose a step-by-step plan using these tools or cheaper alternatives, with the time and cost of each step. Use official pricing pages; say "check pricing" if unsure. 3. Then do the setup with me one step at a time, waiting for my OK before anything that sends messages, posts publicly, spends money or deletes data. 4. Finish with a checklist to run it again next time.
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Guides for this use case
How to get AI code review on your pull requests · How to compare AI models on the same prompt
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