DiffGuardian
Understand a 5,000-line
AI pull request in 5 minutes.
DiffGuardian is AI code review built for the AI era. It reads every PR against your entire codebase and walks you through exactly what changed and why — so you go from open to confident merge in minutes, not hours.
Never merge AI code
you don't understand.
Your agents ship 5,000-line PRs before lunch. DiffGuardian helps you understand the entire change in under five minutes — so you keep human oversight of the code without becoming the bottleneck.
It works. But where is this coupon getting applied?
An agent shipped “add promo codes at checkout.” The tests are green, the AI reviewer said it looks great, the discount lands in the cart. Nobody asked the one question that bites six months from now: is this logic in the OMS, the commerce engine, or Stripe?
Where a feature lives decides how modular, scalable, and refactorable it stays. “It works” was never the hard part.
That’s why understanding how the AI wrote the code is so critical — and why nobody can spend hours reverse-engineering a 5,000-line PR to find out. DiffGuardian’s features give the engineer or architect the full picture, in minutes.
The diff is too big to read.
So “LGTM” becomes a reflex.
When a human wrote 200 lines a day, reading every line worked. Now an agent opens a 5,000-line PR across forty files before standup — far more than anyone can actually read, so “approve” quietly turns into a formality and the bugs ride along into production.
We were merging AI PRs we hadn't really read. DiffGuardian is the first tool that made the review feel faster than writing the code did.
LOGO Reserved for an early customerPlaceholder testimonial — swap in a real quote at launch
Not another line-by-line linter.
A reviewer that understands the change.
DiffGuardian reads each PR against your whole codebase — the way a senior engineer would — then walks you through what it found in plain English.
It walks you through the PR, one feature at a time
Hit "Walk me through this" and a 5,000-line PR becomes a guided tour — broken into the features it actually ships, each explained in plain English. You approve having seen the whole thing, not skimmed a diff.
Try it on a live PR →Reviewed against your entire repo
Rooted in your full codebase, not just the diff — so it catches the ripple effects and broken contracts a diff-only read slips past.
Checks the PR against what it promised
Maps each criterion to the code that satisfies it — see at a glance which are met, partial, or missing before anything merges.
Reviewing a PR is one moment.
Understanding the code is the whole job.
The same guided walkthrough works whether you're approving a teammate's pull request or making sense of what your own agents just built. Anywhere AI wrote code faster than a human can read it, DiffGuardian is how you catch up.
Approve with real understanding
A teammate — or an agent — opens a 5,000-line PR. DiffGuardian walks you through every feature it ships before you click approve, so “LGTM” means you actually get it, not that you gave up reading.
Understand what your agents just built
You kicked off a long multi-agent run and came back to a massive feature spanning forty files. Before you even open a PR, step through what it built — what each piece does and why — so it becomes your code, not a black box you're forwarding on.
Connect a repo. Open a PR.
Understand it in four steps.
Connect your repo
Link GitHub or GitLab in a click. DiffGuardian indexes the whole codebase as review context.
It reads the PR
Every change is analysed against the full repo — features identified, summaries written, criteria checked.
Walk through it
Step through each feature with a guided walkthrough. Filter the diff by feature or acceptance criterion.
Merge with confidence
Approve knowing exactly what shipped and why. Decisions sync straight back to your provider.
Pick a feature. Walk through the change.
A real slice of the DiffGuardian review surface. Choose a feature on the left, then step through the walkthrough — it moves across every file the feature touches.
Free to start. 20% off paid plans
for your first 3 months on the early list.
- 1 connected repo
- Limited AI reviews each month
- Basic AI summaries
- Whole-codebase walkthroughs
- Acceptance-criteria checking
- Everything in Basic
- All AI features unlocked
- Whole-codebase walkthroughs
- Acceptance-criteria checking
- GitHub & GitLab sync
- Everything in Pro, per seat
- Starts at 5 seats
- SSO & SAML
- AI policy enforcement
- Dedicated support
20% early-list discount applies to your first 3 months on Pro or Teams · Teams billed per seat from 5 seats · cancel anytime.
first 3 months.
Join the early list today and lock in 20% off DiffGuardian for your first three months — on whichever plan you choose at launch. No card required now.
in line.
We're onboarding early teams in small waves. Claim your spot now to get in ahead of launch — and lock in 20% off your first three months while you're there.
- 20% off your first 3 months, locked in
- Priority access as we onboard in waves
- A direct line to the founders for feedback
Good questions, answered.
What exactly does the early list get me?
How is this different from my existing code-review tools?
Which providers do you support?
When does it launch?
Is my code safe?
Know what you're merging.
Get 20% off while the early list is open.
Join the developers who refuse to approve code they haven't understood.