aicoolies logo

DevOps Engineer Stack

varies

Infrastructure as code, CI/CD pipelines, and monitoring — the tools a DevOps engineer lives in.

Share

AI at the Command Line

DevOps engineering is inherently a terminal-centric discipline, and the DevOps Engineer Stack reflects this reality by centering every tool around command-line workflows. Claude Code serves as the AI agent that augments a DevOps engineer's capabilities directly in the terminal — the environment where infrastructure work actually happens. DevOps tasks involve writing Dockerfiles, composing docker-compose configurations, crafting CI/CD pipeline definitions, debugging network issues, analyzing log streams, and managing server configurations. These are text-heavy, context-rich operations where an AI agent that understands infrastructure patterns provides enormous leverage. Claude Code reads your repository's infrastructure files — Dockerfiles, GitHub Actions workflows, Kubernetes manifests, Nginx configurations, shell scripts — and provides intelligent assistance across all of them. Ask it to write a multi-stage Docker build that minimizes image size, and it produces a Dockerfile with proper layer caching, non-root user execution, and Alpine-based final stages. Ask it to debug a failing CI pipeline, and it reads the workflow YAML, the error logs, and the relevant configuration files to identify the root cause. For DevOps engineers who spend their days solving complex infrastructure puzzles, Claude Code acts as an always-available infrastructure expert that can reason about system architecture, suggest security hardening measures, and generate configuration files that follow industry best practices.

Self-Hosted Platform Engineering with Coolify

Coolify is the self-hosted PaaS that DevOps engineers deploy on their own infrastructure to provide Heroku-like developer experience without the Heroku price tag or vendor lock-in. For DevOps teams, Coolify replaces a complex stack of Nginx reverse proxy, Let's Encrypt certificate management, Docker orchestration, and deployment scripting with a single, cohesive platform. Coolify supports deploying applications from Git repositories (GitHub, GitLab, Bitbucket, Gitea), Docker images, and Docker Compose files. It manages SSL certificates automatically, provides zero-downtime deployments through blue-green or rolling strategies, monitors container health, and aggregates logs from all deployed services. The multi-server support allows DevOps engineers to manage a fleet of servers from a single dashboard — deploying frontend applications to edge servers, backend services to compute-optimized servers, and databases to storage-optimized instances. Coolify also provides one-click deployment of common infrastructure services: PostgreSQL, MySQL, MariaDB, MongoDB, Redis, RabbitMQ, MinIO, and more. For small to medium teams that do not need the complexity of Kubernetes but have outgrown manual Docker deployment, Coolify hits the sweet spot. DevOps engineers can set up a complete deployment platform in under an hour, then hand off the deployment workflow to developers who push to Git and see their changes live without understanding the underlying infrastructure.

CI/CD Pipelines: From YAML to Code

GitHub Actions provides the CI/CD pipeline layer, and for DevOps engineers in 2026, it has become the dominant pipeline platform due to its tight integration with GitHub repositories, extensive marketplace of community actions, and generous free tier. A DevOps engineer crafts GitHub Actions workflows that automate the entire software delivery lifecycle: code linting and formatting checks on pull requests, unit and integration test execution with service containers (PostgreSQL, Redis), Docker image building and pushing to container registries, security scanning with tools like Trivy and Snyk, infrastructure validation with terraform plan, and production deployment triggered by release tags or manual approval gates. GitHub Actions matrix strategy enables testing across multiple environments simultaneously — different Node.js versions, different operating systems, different database versions — ensuring compatibility before deployment. Reusable workflows allow DevOps engineers to define organizational CI/CD standards that individual teams inherit, providing consistency without micromanagement. The self-hosted runner option lets teams run CI jobs on their own infrastructure for sensitive workloads or specialized hardware requirements. Secrets management integrates with GitHub's encrypted secrets and environment protection rules, ensuring that production credentials are only accessible to workflows running against protected branches with required approvals.

Dagger represents a paradigm shift in how DevOps engineers define and maintain CI/CD pipelines. Traditional CI pipelines are defined in YAML — GitHub Actions workflows, GitLab CI configurations, Jenkins pipelines — and YAML-based pipelines suffer from fundamental limitations: no type checking, no local testing, no composability, and vendor lock-in to specific CI platforms. Dagger solves these problems by letting you define your entire CI/CD pipeline as code in a real programming language — TypeScript, Python, or Go. A Dagger pipeline is a directed acyclic graph of containerized operations that run identically on your laptop and in CI. This means a DevOps engineer can write a pipeline locally, test it by running it against their development environment, debug failures with standard debugging tools, and then deploy the same pipeline to any CI platform without modification. Dagger modules are composable and shareable — the Dagger ecosystem includes modules for Docker builds, Helm deployments, Terraform operations, database migrations, and cloud provider integrations. For DevOps engineers frustrated by debugging YAML indentation errors and platform-specific CI quirks, Dagger provides the engineering rigor they apply to application code but have been missing in their pipeline definitions. The portability guarantee means that if your organization switches from GitHub Actions to GitLab CI or self-hosted runners, your Dagger pipelines work without changes.

Performance Testing Before Production

k6 is the performance testing tool that DevOps engineers use to validate that infrastructure can handle production traffic before it arrives. Built by Grafana Labs and written in Go, k6 executes load tests defined in JavaScript with exceptional efficiency — a single machine can simulate thousands of concurrent virtual users generating hundreds of thousands of requests per second. DevOps engineers write k6 scripts that model real user behavior: login sequences, API call patterns, file uploads, WebSocket connections, and multi-step transactions. These scripts run against staging environments to establish performance baselines, identify bottlenecks, and validate that infrastructure changes (server scaling, database tuning, CDN configuration) actually improve performance. k6 provides detailed metrics including request duration percentiles (p50, p95, p99), throughput, error rates, and connection timing breakdowns. Thresholds allow automated pass/fail criteria — if p95 response time exceeds 500ms or error rate exceeds 1%, the test fails and the deployment is blocked. Integration with GitHub Actions means performance tests run automatically as part of the deployment pipeline, catching performance regressions before they reach production. For DevOps engineers responsible for SLA compliance and infrastructure capacity planning, k6 provides the data-driven evidence needed to make scaling decisions with confidence rather than guesswork.

The Bottom Line

Ghostty ties the DevOps stack together as the terminal emulator where all of these tools converge. A DevOps engineer's typical screen layout involves multiple terminal panes: one running Claude Code for AI-assisted infrastructure work, another tailing production logs, a third executing k6 load tests, and a fourth SSH-ed into a server for debugging. Ghostty's GPU-accelerated rendering handles this multi-pane workflow without the input lag or rendering artifacts that plague Electron-based terminals when processing high-throughput log streams. Its native performance means that scrolling through thousands of lines of Docker build output or k6 test results remains smooth and responsive. The combination of all six tools creates a DevOps workflow that is both powerful and streamlined. A typical day might involve: using Claude Code to write a Dagger pipeline for a new microservice, testing it locally before pushing, creating a GitHub Actions workflow that invokes the Dagger pipeline on pull requests, deploying the service to Coolify with automatic SSL and health checks, running k6 load tests to validate performance under expected traffic patterns, and using Claude Code again to analyze the k6 results and suggest infrastructure optimizations. Every step happens in the terminal, every tool integrates with the others through standard Unix interfaces (stdin, stdout, exit codes, environment variables), and the AI agent is available at every stage to assist with the complex, context-heavy decisions that define DevOps engineering.

Stack Overview

ToolRolePricingOpen Source
Claude CodeAI Agent for IaCIncluded with Claude Pro/Max or API usageYes
CoolifySelf-Hosted PaaSFree (self-hosted) / Cloud from $5/moYes
GitHub ActionsCI/CDFree for public repos with standard runners; private repo minutes: Free 2,000/mo, Pro/Team 3,000/mo, Enterprise Cloud 50,000/moNo
GhosttyTerminalFreeYes
DaggerPipeline EngineFree (open-source) / Dagger Cloud from $0Yes
k6Load TestingFree (open-source) / Grafana Cloud k6 paid tiersYes