The Kerno blog
Engineering notes, guides, and product updates from Kerno.
Introducing Kerno v1, the AI runtime QA engineer for your backend
Kerno v1 tests your user flows, APIs, MCP servers and queues against your real stack from inside Claude Code, Cursor or Codex, and catches bugs before they merge.
All posts
- No. 69News
Kerno tests MCP servers at runtime
Kerno now tests MCP servers at runtime. It introspects your server, plans scenarios per tool, and verifies findings against your live stack.
Sean MadiganAug 11, 2026 - No. 68AI Builder Series
How To Use Skills To Write Better PRDs and Tickets
Using Skill.md and MCP to automate ticket creation with the full context of your product.
Maxi DeloMar 9, 2026 - No. 67AI Builder Series
The Halting Problem in AI Coding
No algorithm can predict all program behaviour not even AI. The only way to know is to run the code.
Dr. Michael CoughlanMar 3, 2026 - No. 66AI Builder Series
LLM-as-a-Judge: Evaluating Output Without a Ground Truth
How to evaluate LLM output when there's no exact answer. Covers configuration, failure modes, and deployment patterns for LLM-as-a-judge.
Dr. Michael CoughlanFeb 23, 2026 - No. 65AI Builder Series
Multi-Agent Validation Gates: Why Claude Can't Break Our Architecture
Multi-stage validation gates catch architectural violations before AI-generated code reaches production.
Jordan BerginFeb 16, 2026 - No. 64AI Builder Series
Runtime evaluation of coding agents
Why coding agents win: how evaluation by execution creates a neurosymbolic feedback loop for objective truth and architectural reliability in AI.
Dr. Michael CoughlanFeb 10, 2026 - No. 63AI Builder Series
Understanding the LLM Marginal Costs
Learn why the era of cheap AI is over, and how tracking every token could mean the difference between profit and bankruptcy.
Sean MadiganFeb 9, 2026 - No. 62AI Builder Series
AI-DLC Startup Edition
Here is how 50 AI native startups and scaleups with over 1 billion dollars in funding are building software in the age of AI.
Sean MadiganFeb 3, 2026 - No. 61AI Builder Series
Building Trustworthy Agents: The Business Case for Rigorous Evaluation Frameworks
Why agents need evals, and bias checks, how they differ from writing traditional software, and how feedback loops are critical for building AI systems.
Dr. Michael CoughlanJan 27, 2026 - No. 60AI Builder Series
Bulk Testing Docker Agent Performance Across 18 Codebases
Using CLI tooling to bulk run testing pipelines across 18 different codebases.
Antoine FrauDec 15, 2025 - No. 59AI Builder Series
Lessons from Biology for Scalable Compute Experiments
Organisations skills for computational experiments - advice from biology that is essential for working with LLMs and agents.
Dr. Michael CoughlanDec 15, 2025 - No. 58AI Builder Series
CLI Tooling for Agent Testing Pipelines
How we built a CLI tool that automates Docker Compose experiments from YAML, running them in sequence for LLM-based evaluation.
Antoine FrauDec 8, 2025 - No. 57AI Builder Series
An Agent Evaluation Study: Assessing User Input in Test Plan Generation
How freeform user input can impact test planning negatively.
Dr. Michael CoughlanDec 1, 2025 - No. 56AI Builder Series
Why the AI Bubble Matters Less to Builders Than People Think
AI builders shouldn’t fear a bubble; the real risk is rising token and inference costs as subsidies fade, scaling ends, and energy limits tighten.
Dr. Michael CoughlanNov 24, 2025 - No. 55AI Builder Series
How Local Prompt Caching Reduces Tokens in Tool-Driven LLM Workflows
Prompt caching prevents token bloat by storing static context so multi-step agent workflows stay fast, cheap, and scalable instead of growing exponentially.
Jordan BerginNov 14, 2025 - No. 54AI Builder Series
Teaching Agents to Write and Self-Correct End-to-End Test Scenarios
How agents generate test scenarios, run them, learn from errors, and refine each step to deliver stronger end to end testing with minimal input.
Jordan BerginNov 14, 2025 - No. 53AI Builder Series
Giving the Kerno Agent Agency to Create Docker Compose
Giving the LLM agent the agency to read, diagnose, modify, and regenerate Docker Compose files on its own.
Jordan BerginNov 10, 2025 - No. 52AI Builder Series
Turning Code into a Visual Graph: How We're Using Memgraph for Indexation
We are integrating Memgraph Lab for visual code indexing, to export graph state for debugging and make the graph easier to explore.
Sean MadiganNov 10, 2025 - No. 51AI Builder Series
Improving Trace Visibility and Reproducibility in Langfuse
A look at recent Langfuse updates that make tracing, cost tracking, and debugging agent runs clearer, more detailed, and easier to reproduce.
Antoine FrauNov 10, 2025 - No. 50AI Builder Series
Introducing The AI Builder Series: Sharing tribal knowledge around building with AI
Introducing the AI Builder Series, where engineers that are building with AI share their experiences.
Sean MadiganNov 10, 2025 - No. 49Other
When Collaboration Becomes Counterproductive for Engineers
While collaboration is essential, its misuse in problem-solving can prolong issues and magnify costs.
Sean MadiganNov 9, 2025 - No. 48Guides
DevOps Pipeline - Understanding the Steps, Benefits, and Tools for Developers
DevOps is a methodology that stemmed from the need to involve cross-functional teams, systematize code delivery, and...
Vladimir RomanovNov 9, 2025 - No. 47Guides
eBPF – The Best Kept Secret in Technology
eBPF enables low-overhead, real-time observability and security, powering AI-native apps without sidecars, agents, or manual instrumentation.
Sean MadiganNov 9, 2025 - No. 46Guides
Network Observability
Observability is used to describe the ability to understand the current or past state of a software system.
Vladimir RomanovNov 9, 2025 - No. 45Guides
Programming the Kernel with eBPF
Learn about eBPF, an exciting new technology that makes programming the kernel flexible, safe, and accessible to developers.
Karim TraiaiaNov 9, 2025 - No. 44Other
Truck Factor: The Silent Debt
Explore the Truck Factor, its impact on engineering teams, and strategies to prevent knowledge silos from stalling development.
Sean MadiganNov 9, 2025 - No. 43Guides
Understanding What is ECU in AWS
An ECU is an EC2 Compute Unit used to measure the power of resources in the cloud. Based on that single ECU, the user can...
Vladimir RomanovNov 9, 2025 - No. 42Guides
DevSecOps with GitLab CI
A practical guide to DevSecOps with GitLab CI, wiring automated security testing into every stage so security becomes a shared responsibility.
Vladimir RomanovSep 5, 2024 - No. 41Guides
CI CD Pipelines with GitHub Actions
Continuous integration (CI) is a practice to automate the process of code management. It usually means integrating your code changes into a specific branch.
Vladimir RomanovJul 3, 2024 - No. 40Guides
IAM Roles for Service Accounts
In AWS, there are two ways to apply the Principle of Least Privilege, which are through IAM to provide granular permissions to access the AWS resources.
Vladimir RomanovJul 2, 2024 - No. 39Guides
GitOps with Kubernetes
GitOps is a practice that uses Git repositories as the source of truth for declarative infrastructure and application management.
Vladimir RomanovJun 10, 2024 - No. 38Guides
Kubernetes Monitoring | Tools & Techniques You Should Know
In this article, we will talk about some important concepts in monitoring and popular monitoring tools that you should know about their main features.
Vladimir RomanovMay 14, 2024 - No. 37Guides
Exploring Amazon EKS Cluster Management with EKSCTL: A Comprehensive Overview
Amazon EKS is the managed service that removes control plane administration from a Kubernetes cluster. Here is how to run one with eksctl.
Vladimir RomanovApr 30, 2024 - No. 36Guides
Kubernetes Ingress: Efficient Strategies for Service Routing
Kubernetes Ingress is an API object managing external access to services in a cluster, with load balancing, SSL termination, and more.
Vladimir RomanovApr 24, 2024 - No. 35Guides
Configuring Static Linux IP Addresses Running on Virtualized Hardware Using Proxmox Dell PowerEdge R730xd Server
In this tutorial, we’re going to walk through the required steps to set an IP address for a Ubuntu server Virtual Machine (VM).
Vladimir RomanovApr 20, 2024 - No. 34Guides
How to Manage Kubernetes Clusters, Deployments, Nodes, and Pods via K9S
In this tutorial, we’ll take a look at K9s - We’ll understand what it is, how to install it, how it helps engineers work with cluster components, and...
Vladimir RomanovApr 19, 2024 - No. 33Guides
Introduction to Kubernetes Lens
Kubernetes Lens is a desktop tool that comes to make easier and faster the visualization and troubleshooting of multiple Kubernetes clusters.
Vladimir RomanovApr 16, 2024 - No. 32Guides
Kubernetes Services - ClusterIP, NodePort, LoadBalancer, and more
Kubernetes Services are essential components for enabling communication within a Kubernetes cluster and facilitating connectivity to applications.
Vladimir RomanovApr 10, 2024 - No. 31Guides
Elevating Kubectl | Exploring Kubernetes Contexts
Kubernetes Context includes all the information required to connect to a Kubernetes cluster, like cluster hostname, port, and authentication method.
Vladimir RomanovApr 2, 2024 - No. 30Guides
Kubernetes Dashboard - Deploy and Visualize your Kubernetes Cluster
The Kubernetes Dashboard is a web-based Kubernetes user interface. It has tons of features including the overview of the cluster, managing cluster resources.
Vladimir RomanovMar 18, 2024 - No. 29Guides
Harnessing the Power of Generative AI with AWS Bedrock: A Step-by-Step Guide
Generative AI lets machines produce text, images, and code. This is a step-by-step guide to building with it on AWS Bedrock.
Vladimir RomanovMar 14, 2024 - No. 28Guides
Serverless Architectures & AWS Lambda Introduction
Delve into the realm of AWS Lambda and serverless architectures with this comprehensive article. From an introduction to hands-on creation and testing.
Vladimir RomanovMar 12, 2024 - No. 27Guides
K8S Microservices Architecture Deployment
A walkthrough of deploying several microservices onto a Kubernetes cluster, using an architecture representative of a real production workload.
Vladimir RomanovMar 7, 2024 - No. 26Guides
OOMKiller & Exit Code 137
Understand and learn how to troubleshoot the Kubernetes OOMKilled (Exit Code 137) error.
Vladimir RomanovMar 7, 2024 - No. 25Guides
Jira Automation | Expand its power with AWS SSM
You will learn to use AWS SSM to expand the power of Jira with its automation feature and inspire you to design automation rules for your DevOps solution.
Vladimir RomanovFeb 21, 2024 - No. 24Guides
Deploying Your First Pod in Kubernetes
Our goal for this tutorial is to deploy our first pod within Kubernetes. We’re going to cover every step on how to write up the YAML file for deployment.
Vladimir RomanovFeb 13, 2024 - No. 23Guides
Kubernetes Services
A Kubernetes Service ties pods and nodes together, providing the plumbing inside a cluster. Covers ClusterIP, Headless, NodePort, and LoadBalancer.
Vladimir RomanovFeb 9, 2024 - No. 22Guides
Getting Started with Bash Scripting
Bash, or Bourne Again SHell, is a scripting language commonly used by system administrators of the Linux platform. Bash allows for simple automation.
Vladimir RomanovJan 19, 2024 - No. 21Guides
AWS ECS | Docker, Virtualization, Fargate, Containers, and more
Amazon ECS is a container orchestration service covering deployment, management, and scaling. Here is how it works with Docker and Fargate.
Vladimir RomanovJan 17, 2024 - No. 20Guides
How to Uncommit in Git
How to uncommit in Git, reversing your edits and restoring files to the previous commit, with the trade-offs of each approach.
Vladimir RomanovJan 15, 2024 - No. 19Guides
YAML File Format - Complete Guide on Syntax, Arrays, Comments, Examples, etc.
YAML File Format - Complete Guide on Syntax, Arrays, Comments, Examples, JSON vs YAML vs XML, etc.
Vladimir RomanovJan 11, 2024 - No. 18Guides
AWS CloudFront and Content Delivery Networks (CDN)
AWS CloudFront lets system administrators deploy content across the globe. Here is what a CDN does and how CloudFront delivers it.
Vladimir RomanovJan 8, 2024 - No. 17Guides
Kubernetes Operators
Kubernetes Operators are often used to automate a piece of infrastructure and allow for granular control on how deployments are observed, how pods...
Vladimir RomanovJan 7, 2024 - No. 16Guides
Kubectl Logs Tail | How to Tail Kubernetes Logs
Kubectl Logs Tail | The kubectl logs tail command is critical in troubleshooting Kubernetes based applications and understanding what’s going on inside...
Vladimir RomanovJan 5, 2024 - No. 15Guides
How to Install Kubernetes
Installing Kubernetes - In this technical tutorial we'll provide multiple ways to installing and running kubernetes on a local machine.
Vladimir RomanovJan 3, 2024 - No. 14Guides
Master Kubernetes Node Commands: The Ultimate kubectl Commands and Cheat Sheet for Node Operations
Explore essential Kubernetes commands for efficient cluster management, including kubectl get, exec, and rollout, vital for system admins and devs.
Vladimir RomanovDec 22, 2023 - No. 13Guides
Essential Kubernetes Skills: How to Get Logs from Pods Using kubectl
Learn to use kubectl for Kubernetes: Get logs from specific pods, understand namespaces, and handle logging tasks efficiently.
Vladimir RomanovDec 21, 2023 - No. 12Guides
Mastering Pod Deletion in K8s: A Guide to Using kubectl for Removing Pods
A guide to pod management in Kubernetes, covering how to delete and remove pods with kubectl and what happens to the workload when you do.
Vladimir RomanovDec 21, 2023 - No. 11Guides
How to Restart Kubernetes Pods With kubectl
A look at a few different methods for restarting Kubernetes pods with kubectl, and when each one is the right choice.
Vladimir RomanovDec 13, 2023 - No. 10Guides
What is AWS VPC | Tutorial on VPC Architecture, Subnets, Pricing, Endpoints, Best Practices, and More
AWS Virtual Private Cloud, or VPC, can be thought of as a network-based segmentation for resources that run in AWS.
Vladimir RomanovDec 12, 2023 - No. 09Guides
AWS Route 53 – What It Is, How It Works, and Integration With Other Services
Route 53 is Amazon's cloud DNS service, connecting user requests to services running in AWS. Here is how it works and what it integrates with.
Vladimir RomanovDec 6, 2023 - No. 08Guides
AWS EBS - The Complete Guide
Learn everything you need to know to get started with Amazon Elastic Block Storage (EBS).
Vladimir RomanovOct 17, 2023 - No. 07Guides
AWS ELB - The Complete Guide
Learn everything you need to know to get started with the AWS Elastic Load Balancer (ELB), from load balancer types to health checks and SSL.
Vladimir RomanovOct 17, 2023 - No. 06Guides
AWS EC2 The Complete Guide
Learn everything you need to know to get started with Amazon Elastic Compute Cloud (Amazon EC2).
Vladimir RomanovOct 12, 2023 - No. 05Guides
Creating an AWS AMI - Amazon Machine Image
Amazon Machine Images are custom EC2 Instances that offer repeatability and fast deployment of underlying software. The goal of an AMI is to...
Vladimir RomanovSep 27, 2023 - No. 04Guides
How to Create a Retention Rule for EBS Volumes via EBS Recycle Bin
The EBS Recycle Bin is a service used for protecting EBS Snapshots and Amazon Machine Images [AMI]s from accidental deletion.
Vladimir RomanovSep 24, 2023 - No. 03Guides
How to Copy an EBS Snapshot to a Different Availability Zone
EBS Volumes are created inside of a specific Availability Zone [AZ]. It isn’t possible to move an EBS Volume from one AZ to another directly.
Vladimir RomanovSep 23, 2023 - No. 02Guides
How to Create an EBS Volume from an EBS Snapshot
An EBS Snapshot is nothing more than a backup of an EBS Volume. It can’t be attached to an instance, the user can’t read any data from it.
Vladimir RomanovSep 23, 2023 - No. 01Guides
How to Connect to EC2 Instance Using Instance Connect
Learn how to connect to an AWS EC2 instance using Instance Connect.
Vladimir RomanovSep 20, 2023
No posts match your search.