cubic

AI code review that catches hard bugs and scans your whole codebase

Hand-reviewed by the Toolglade team·Updated Aug 2026

code-review#ai-code-review#pull-requests#github#bug-detection

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Toolglade’s take

cubic stands out among the crowded AI code-review space by topping an independent third-party benchmark and emphasizing low false-positive rates, which is the metric that actually determines whether teams keep a bot enabled. The codebase-wide agent scans on the Pro plan push it beyond simple PR commenting into continuous security and quality monitoring. It is GitHub-only, so GitLab or Bitbucket shops are out of luck. As a young YC startup, its long-term roadmap and enterprise depth are still proving out.

About cubic

cubic is a YC-backed AI code review tool for GitHub that delivers low-false-positive PR reviews and, on Pro, runs scheduled agent fleets to scan the whole codebase and generate fix PRs.

cubic (YC X25) is an AI code review platform for teams building on GitHub. On every pull request it provides instant reviews that find bugs, suggest improvements, enforce coding standards, and can automatically write PR descriptions, aiming for fewer false positives than the industry average so reviews stay signal-rich. Teams report merging PRs meaningfully faster with cubic in the loop. Beyond per-PR review, cubic's Pro plan runs thousands of AI agents on a schedule to continuously scan the whole codebase for bugs and security issues, triage what it finds, notify code owners, create tickets, and even generate one-click fix PRs. In one example it caught eleven critical vulnerabilities in a Cloudflare plugin shipped to a government property, illustrating a focus on catching hard, high-impact issues. cubic ranked #1 on Martian's independent AI code review benchmark with a 61.8% F1 score and is used by companies including PostHog, n8n, and Cal.com. User code is kept private and never stored or used for training. It is free for public open-source repos, with a paid Team plan for private repositories.

TL;DR

cubic is a YC-backed AI code review tool for GitHub that tops an independent benchmark, delivers low-false-positive PR reviews, and runs scheduled agent fleets to scan the whole codebase.

Company overview

cubic is a Y Combinator (X25) startup building AI code review tooling for engineering teams on GitHub. It has quickly gained adoption among developer-focused companies like PostHog, n8n, and Cal.com.

The company differentiates on independently benchmarked accuracy and low false positives, and on extending code review into continuous codebase-wide scanning. It positions itself against incumbents in the AI code-review space.

Product features

cubic reviews every pull request to find bugs, suggest improvements, enforce standards, and write PR descriptions. Its Pro plan runs scheduled fleets of AI agents that scan the entire codebase for bugs and security issues, triage findings, notify owners, create tickets, and generate one-click fix PRs.

It keeps user code private and unused for training, and is free for public open-source repos. It ranked #1 on Martian's independent AI code review benchmark, underscoring an accuracy-first approach.

Target market

cubic targets software engineering teams and open-source maintainers who use GitHub and want accurate, low-noise automated code review plus continuous codebase security scanning.

Buyer personas

End users

Software engineers and reviewers working in GitHub pull requests.

Buyers

Engineering managers and security leads adopting code-review automation.

Key influencers

Staff engineers, open-source maintainers, and DevEx teams.

Ideal customer profile

GitHub-based engineering teams that want benchmarked, low-false-positive AI code review and continuous whole-codebase scanning, especially security-conscious startups.

Funding & performance

Y Combinator X25 batch; early-stage venture backing (verify with vendor).

Pros & cons

Pros

Ranked #1 on an independent code-review benchmark
Emphasis on low false-positive rate
Codebase-wide scheduled agent scans on Pro
One-click fix PRs and auto-triage
Free for open-source public repos
Code kept private and not used for training

Cons

GitHub-only, no GitLab or Bitbucket
No self-hosted option
Young startup with evolving enterprise features
Pro automation may need tuning
Limited public API

Key features

Team collaboration

Multi-language

Integrations

GitHub

Input types

text

Output types

text

Best For

Pull request review, Codebase security scanning, Engineering teams on GitHub

Compare key features

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Feature

cubic

Baz

Ellipsis

Pricing

Freemium

Free plan

Yes

Free trial

Yes

API

Yes

Self-hosted

Yes

Team support

Yes

Frequently asked questions

Which platforms does cubic support?+

cubic integrates with GitHub for pull request review and codebase scanning. It does not currently support GitLab or Bitbucket.

Is cubic free for open source?+

Yes. cubic is free for public open-source repositories. Private repositories require the paid Team plan at $40 per developer per month.

Does cubic use my code to train its models?+

No. cubic states that user code remains private and secure and is never stored or used to train its AI.

What does the Pro plan add?+

Pro runs thousands of AI agents on a schedule to scan the entire codebase for bugs and security issues, triage findings, notify owners, create tickets, and generate one-click fix PRs.

How accurate is cubic?+

cubic ranked #1 on Martian's independent AI code review benchmark with a 61.8% F1 score and reports fewer false positives than the industry average.