# FAQs

<details>

<summary>What is Kerno?</summary>

Kerno is a validation engine that helps you catch breaking changes in your AI backend code before raising your PR.

Kerno analyzes your codebase and repository context to automatically generate, run, and maintain high-quality integration tests. When you make changes, Kerno validates them against your existing functionality to detect breaking changes and unintended side effects.

Everything happens directly in your IDE, giving you instant feedback without waiting for CI pipelines. This means you can validate changes in seconds, stay in flow, and ship faster.

</details>

<details>

<summary>What makes Kerno different from other tools</summary>

Kerno is purpose built for backend integration testing. It automatically adds new tests as features and edge cases appear, and retires outdated ones as code evolves. This keeps your test suite complete and consistent across the whole engineering team, with no manual effort required.

Kerno also handles the setup and execution. It spins up dependencies, generates and seeds data, runs tests in parallel for quick feedback, and self-heals when changes or failures occur.

By tightening feedback loops and removing test maintenance, it frees engineers to focus on building.

</details>

<details>

<summary>Does Kerno support my backend stack?</summary>

Kerno currently supports TypeScript, Python, and JavaScript. We're actively working on expanding support to all major backend languages.

Performance varies by language based on the availability of training data. You'll see the best results with popular languages that have extensive public codebases and documentation.

</details>

<details>

<summary>Does Kerno store my code</summary>

Your code never leaves your machine. The codebase index is stored locally, and your code runs in a secure, isolated environment during testing.

We maintain a zero-day retention policy with all our service providers, meaning any data processed is immediately deleted and never stored.

Your code remains completely private and inaccessible to anyone, including our team.

</details>

<details>

<summary>Does Kerno use my code for training or fine tuning LLMs?</summary>

We only use public data to train our system. Your private code is **strictly off-limits** and will never be used for training purposes.

</details>

<details>

<summary>What there discounts available for startups</summary>

Kerno offers free usage for qualified Open Source Projects and a significant discounts for pre-Series A startups. [Drop us a note](https://www.kerno.io/contact) to check your availability.

</details>

{% hint style="info" %}
If you encounter issues or have questions, [message us on Discord](https://discord.gg/k8yA9tZdP9), and we’ll gladly help.
{% endhint %}


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