Runs in every coding session against your running app and dependencies to catch real regressions and security issues your agent and code review tools miss.
What engineering teams say about shipping with Kerno.
Kerno was up and running in minutes with no manual work, and it made our API migration so much smoother. We could instantly validate that every change made by Cursor worked the way we expected, and now it’s a core part of how we build.
Using Kerno with Claude Code has been a game changer. You get quick feedback with no manual effort, and it saves you a lot of time and hassle debugging integration issues post-merge.
Kerno saves us a lot of manual work and helps us catch side effects and issues that would definitely break our projects’ backends. Our engineering team loves it.
Your coding agent's tests carry the same blind spots as its code. Static review only catches the obvious, and manual checking doesn't scale. Slop piles up, draining engineering time and slowing releases.
Give every developer and agent staff-level testing knowledge to catch the expensive runtime issues DIY testing and code review miss, right at the source.
Kerno catches the functional and security bugs that only surface at runtime, before they ship.
Kerno maps the blast radius of a change and tests every path it touches.
| Assertion | Expected | Received |
|---|---|---|
| response status | 400 | 204 |
| tag row in database | 1 | 0 |
Kerno gives coding agents structured signals and persistent code context on every change.
Kerno writes, runs, and updates your backend tests automatically, so your team catches real bugs without manual effort.
Builds a graph of your codebase and docs, and maps every endpoint and its dependencies.
Creates hundreds of regression, integration, and security tests to capture how your backend works.
Surfaces the exact diffs against your baseline, so you see a change's full impact before it ships.
Retires stale scenarios and writes new ones as your product changes, so the baseline stays accurate.
Static review reads your code and unit tests run on mocks. Kerno catches the functional, security, and edge-case bugs that only surface at runtime.
Verify endpoint behaviour, multi-step request sequences, coordinated service interactions, and integration patterns.
Validate request and response structures, data types, required fields, serialization rules, and version compatibility.
Review token validation, role-based access rules, permission scopes, session handling, and all credential-related flows.
Validate status codes, error body formats, retry behaviour, backoff procedures, timeout handling, and controlled fallbacks.
Validate payload size limits, pagination behaviour, null or empty values, malformed inputs, and constraint-based validation.
Validate broken object- and function-level authorization, injection, excessive data exposure, mass assignment, and SSRF.
Verify each tool your MCP server exposes, including returned content, structured output, schema conformance, and error handling.
Verify how your agent calls tools, chains model steps, and handles streaming responses, with OpenAI, Anthropic, and others mocked for deterministic runs.
It learns your domain logic, your conventions, and your standards, then applies them on every change.
Give Kerno your standards and business rules in plain English, scoped to the repos and paths you choose. It applies them on every run.
Kerno learns from every test run and the feedback you give it, building a sharper model of your codebase and standards over time.
Install Kerno, get full test coverage, and roll out to your team without any friction. Set up once. Zero ongoing maintenance.
Point Kerno at your repo. It maps every endpoint, connects to your live services, and calibrates to how your backend runs.
Kerno creates an extensive suite of baseline tests that capture how each API, task, and event behaves today, across every corner of your codebase.
The Kerno MCP connects to your agents, validating every code change and catching runtime issues before they reach production.
Got any extra questions? Reach out on our community channel and we'll be happy to help.
Kerno verifies the full impact of every code change against your live stack. It covers your HTTP, gRPC, and GraphQL APIs along with your async tasks, message queues, and events, catching the functional, security, and edge-case bugs that only surface at runtime.
Static review reads your code and unit tests run on mocks. Kerno runs your actual code against your live stack and real dependencies, so it catches runtime behaviour that neither one can see.
Yes. Kerno connects to the services and datastores you already run, including PostgreSQL, MySQL, MongoDB, Redis, Kafka, and more, and manages the data layer so it can exercise them the way your application does.
Kerno encrypts everything end to end, never retains your code, and is SOC 2 Type II (audit in progress). Your private code is never stored or used for training.
Kerno connects over MCP to any coding agent, including Claude Code, Codex, Cursor, GitHub Copilot, and more. Your whole team validates every change from the agent they already use.
About an afternoon. Install Kerno, let it baseline your backend, and connect your team. You get full coverage in under a day, and Kerno keeps the suite current with zero ongoing maintenance.
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