Bounded consequence preview
Checking
Review evidence
- Changed files
- 0
- Consequence surfaces
- 0
- Unresolved proof
- 0
What this preview did not verify
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AI pull request safety gate
Stop AI-generated PRs from outrunning review.
Busleyden Guard posts a GitHub check that shows what changed, who should review it, and what evidence is missing. For supported Python authentication changes, it also breaks the changed logic on purpose and verifies that the proposed regression test catches the defect.
- Free on public repos
- Private repos: $19.90/month
- No sales call
No install required
Paste a public PR. See what proof review may be missing.
Guard reads GitHub's public changed-file evidence and returns a bounded consequence preview. It does not execute code or pretend a preview is a complete repository check.
The review bottleneck
More code is cheap. Knowing whether it is safe is not.
AI can create a plausible change in minutes. Senior engineers still have to reconstruct its blast radius, find the right owners, and decide whether the attached proof is enough.
- Reviewer time
- Senior engineers manually trace unfamiliar changes.
- Release delay
- Missing tests and owners appear late in the merge queue.
- Escaped defects
- Small diffs can reach authentication, data, and dependencies.
- Audit exposure
- The reason a risky change merged is often not recorded.
Live counterfactual GitHub proof
It did not merely find a test. It proved the test could catch the defect.
On a public authentication PR, Guard first blocked the change because token-replay evidence was absent. After the test was added, Guard ran it on the PR, removed the new replay protection, and confirmed that the same test failed against the broken counterfactual.
Live GitHub App run / public PR #3
1 proof required
Reject reused authentication tokens
Changed surface
Authentication session handling
Verified owner
@AlexanderLuzDH approved
Mapped test
tests/auth/test_session.py
The only missing proof
- Prove that a replayed or reused token is rejected.
The replay test passed on the PR and failed when Guard removed the replay condition. The next hosted run passed with zero blockers.
From install to merge decision
Set it up once. Let every PR explain itself.
Install on one repository
Connect the GitHub App and approve the setup pull request.
Open a normal pull request
Guard reads the diff, ownership, tests, and scanners, then counterfactually checks supported evidence.
Act on one clear check
Merge, route to the right reviewer, or wait for the exact missing proof.
Inspect before you trust
Do not trust the pitch. Inspect the decision trail.
The public proof includes both content-addressed certificates, both GitHub Checks, the exact code change, the test, and the targeted mutation that the test killed. Guard must earn trust the same way on your repository.
- Before evidence
- Certificate with one blocker
- After evidence
- Certificate with zero blockers
- Public source trail
- PR, commits, review, Checks, and workflow
- What it does not claim
- Guard does not prove that code is bug-free or replace human review.
Designed for a narrow trust boundary
Your source stays in your GitHub workflow.
Start with one selected repository. The analysis runs through GitHub Actions, and customer source code is not stored by Busleyden Guard by default.
- Repository access
- Only repositories you select during installation.
- Source storage
- No customer source-code storage by default.
- Removal
- Uninstall the App and remove the workflow at any time.
Two self-service plans
Public repositories are free. Private repositories are $19.90/month.
Both plans install the GitHub App and produce the same Guard Check. Choose by repository visibility; no call or annual contract is required.
- GitHub Check Run with merge guidance
- Reviewable setup pull request
- No sales call or annual contract
- Self-service installation and removal
The standard to beat