Show HN: Codiff, a local diff review tool

#1

Post by cpojer » Sun, May 17, 2026, 5:30 AM UTC

Nowadays I review a lot of code locally that was written by llms. I used to review my own code using git + delta. It started to feel limiting with the amount of code written by llms.

When looking at a large diff on Friday I pointed an llm at diffs.com and trees.software and told it to build an app. It only took 16 minutes, is extremely fast for large diffs, beautiful and minimal.

Today I polished it up and added all the features that I need. It has file filters, search, an llm walkthrough mode, and review comments that you can paste back into your llm.

I will be using Codiff a lot, and can finally review the large diff from Friday that led me to build this If you like it, fork it!

Show HN: Codiff, a local diff review tool
github.com

Re: Show HN: Codiff, a local diff review tool

#2

Post by sjhalani7 » Sun, May 17, 2026, 5:41 AM UTC

That's awesome. Been reviewing code diffs on the IDE and it's been hard, so will check this out!

Re: Show HN: Codiff, a local diff review tool

#3

Post by atmanactive » Sun, May 17, 2026, 5:55 AM UTC

... for MacOS.

Re: Show HN: Codiff, a local diff review tool

#4

Post by cpojer » Sun, May 17, 2026, 5:59 AM UTC

atmanactive wrote: post #3

... for MacOS.

[dead]

Re: Show HN: Codiff, a local diff review tool

#5

Post by usernametaken29 » Sun, May 17, 2026, 6:37 AM UTC

Surprisingly enough this has just a few features the JetBrains diff view is lacking, notably file search… good ideas

Re: Show HN: Codiff, a local diff review tool

#6

Post by realrocker » Sun, May 17, 2026, 6:53 AM UTC

:) We are all converging on the same problems and tooling to fix them.

Built this in the last couple days to review changes done by claude on a hetzner box(over tailscale on my phone) and leave comments before pushing to remote : https://github.com/livetemplate/prereview.

Runs everywhere and can has a claude skill: /prereview which starts a new instance for the current changes. Has a “Hand-off” button to signal claude to process the comments.

UI is responsive. I use it on my iphone with claude mobile app + /remote-control to leave comments before pushing.Still requires polish but core features work.

Re: Show HN: Codiff, a local diff review tool

#7

Post by amys94fr » Sun, May 17, 2026, 6:58 AM UTC

[dead]

Re: Show HN: Codiff, a local diff review tool

#8

Post by cpojer » Sun, May 17, 2026, 7:02 AM UTC

realrocker wrote: post #6

:) We are all converging on the same problems and tooling to fix them. Built this in the last couple days to review changes done by claude on a hetzner box(over tailscale on my phone) and leave comments before pushing to remote : https://github.com/livetemplate/prereview . Runs everywhere and can has a claude skill: /prereview which starts a new instance for the current changes. Has a “Hand-off” button to signal clau…

That’s awesome! I built this specifically as a GUI because it’s become too much code to effectively review in the terminal for me.

Re: Show HN: Codiff, a local diff review tool

#9

Post by stephenr » Sun, May 17, 2026, 7:03 AM UTC

Who knew that the killer task for LLMs would be "recreate existing things that exist without me mentioning them by name, based on a worse alternative as the example".

Kaleidoscope exists.

File Merge exists.

Re: Show HN: Codiff, a local diff review tool

#10

Post by Evan-Purkhiser » Sun, May 17, 2026, 7:04 AM UTC

realrocker wrote: post #6

:) We are all converging on the same problems and tooling to fix them. Built this in the last couple days to review changes done by claude on a hetzner box(over tailscale on my phone) and leave comments before pushing to remote : https://github.com/livetemplate/prereview . Runs everywhere and can has a claude skill: /prereview which starts a new instance for the current changes. Has a “Hand-off” button to signal clau…

Would love to see some screenshots in your readme of this!