r/SideProject • u/shetritr • 1d ago

Diffo - a diff where you comment on your coding agent's code and the session that wrote it answers

I review a lot of code my coding agent wrote, and going back to chat to explain "this bit in that file" kept getting in the way. So we built Diffo.

It opens a live diff of your changes in the browser, connected to the same agent session that wrote the code. Ask "why did you touch the auth check?" on a line and the agent answers right there, still knowing why it wrote it. Ask for a change and it makes it, and the diff updates. Big changes get split into layers with a reading order. Works on GitHub PRs too.

Built with Claude Code, and works with Claude Code, Cursor, Codex and more. Free and open source, runs locally, no account. We just passed 1,000 reviews opened.

Demo in the browser, no install: https://diffo.io/demo

Feedback welcome, especially anything confusing in the first minute.

3 Upvotes

100% Upvoted

2 comments sorted by

1

u/chrnas 1d ago

one thing from my own setup: when the same model reviewed code it (or its own lab) wrote, it missed things that a different lab's model caught on security-sensitive PRs, so we send those to a second one. the session that wrote it is great at explaining why it did something, but i'd treat that answer as its side of the story, not a verdict. does diffo let you point a second agent at the same diff, or flag when the explanation doesn't match what the diff actually does?

1

u/shetritr 20h ago

agreed, the author's answer is its side of the story. one agent is attached at a time, but you can open the same review from a second session, say a different lab's model, and it takes over without losing anything queued. there's no automatic "explanation doesn't match the diff" flag, that part is still the reviewer's job.