Easy concepts in CI/CD & Automation, page 2
Vagrant: Your Dev Environment as Code
Vagrant is a scriptable remote for virtual machines, defining a dev environment in one text file. It ensures teams have identical, isolated setups, solving "it works on my machine" problems.
Environment Variables: Configuration Outside Code
Environment variables are settings passed to your app from the outside world, letting you change behavior without touching code. Use them for API keys or database URLs. The biggest footgun is committing secrets to version control instead of using variables.
Configuration Files: Separating Code from Settings
A config file separates a program's behavior from its code, allowing you to change settings like database URLs without recompiling. They're used for API keys, feature flags, and environment-specific values. The footgun is committing secrets to version control.
The Twelve-Factor App: Store Config in the Environment
Your app's code is the blueprint; its config is the specific address and utility hookups. Store config—database URLs, API keys—in environment variables, not in the code. The footgun is hardcoding secrets, making your code base impossible to open-source safely.
Software Containers: Portable, Isolated Applications
Think of a container as a standardized box for your app, bundling its code and all dependencies. This lets you run it consistently anywhere, from your laptop to the cloud.
Dockerfile: The Recipe for Your Container
A Dockerfile is a recipe for building a container image. It's a text file of commands that automates an application's environment setup, ensuring it runs identically anywhere. The footgun is creating bloated images with unnecessary build tools.
Container Image: A Blueprint for Your Application
A container image is a static blueprint for your application, bundling code, runtime, and settings. You build images to ship software for Docker or Kubernetes, which then run them as live containers.
Docker Compose: A Tool for Containerized Applications
Docker Compose is a tool in the Docker suite for running applications in containers. It ensures your app runs the same everywhere by packaging it with its dependencies, solving the 'works on my machine' problem.
Rolling Deployment: Update Servers Without Downtime
A rolling deployment upgrades servers one by one, like swapping train cars while the train moves. A load balancer directs users to active servers, keeping the app online. The main footgun is incompatibility between old and new code running at the same time.
Deployment Rollbacks: Your CI/CD Undo Button
A rollback strategy is your CI/CD's undo button, letting you revert to a known good state when a new deployment fails. It's essential for production environments. The biggest mistake is not having one, forcing a frantic 'hotfix' under pressure.
Threat Modeling: Thinking Like an Attacker
Threat modeling is thinking like an attacker to find security flaws before they're exploited. It systematically analyzes your system to prioritize defenses against the most likely threats. The footgun is treating it as a one-off task, not a continuous process.
SAST: A Security Spellchecker for Your Code
SAST is like a spellchecker for security, scanning your source code for vulnerabilities before it ever runs. It integrates into your CI/CD pipeline to give feedback on every commit. The main footgun is noise: false positives can overwhelm developers.
Software Composition Analysis (SCA): Know Your Dependencies
Software Composition Analysis (SCA) is like checking the ingredient list for your software. It scans the open-source libraries you use for known vulnerabilities, license issues, and outdated versions.
Observability: Seeing Inside Your System
Observability is the ability to ask new questions about your system's health without shipping new code. It's crucial for debugging distributed systems and is the first step in triaging an outage.
APM: Turning System Metrics into Business Meaning
APM turns system metrics into business meaning by tracking software performance and availability. It matters most when slowdowns threaten service levels. The footgun is gathering data without translating IT metrics into what the business actually cares about.
Structured Logging: Logs as Data, Not Strings
Treat logs as structured data (like JSON), not just plain text. This makes them machine-readable and queryable, letting you filter, search, and create dashboards on specific fields (e.g., user_id, trace_id).
Bug Tracking Systems: The Central Log for Software Defects
A bug tracker is the central log for a project's known defects. It’s used in software development to keep track of reported bugs, coordinate fixes, and manage the lifecycle of an issue. The footgun is undervaluing the quality of bug reports.
Kustomize: Template-Free Kubernetes Configs
Kustomize manages environment-specific Kubernetes configs by layering patches on a base YAML, avoiding complex templating. Use it to tweak deployments for dev, staging, or prod. The footgun: the kubectl version can lag, causing unexpected behavior.
Platform Engineering: Paving the Road for Developers
Platform engineering builds a paved road for developers, offering a standardized, self-service path to ship code. It's used to reduce developer cognitive load and enforce standards. The footgun is building a platform so rigid that nobody wants to use it.
Internal Developer Platform: Your Org's 'Easy Button'
An Internal Developer Platform (IDP) is your company's internal 'PaaS,' offering a self-service 'easy button' for common developer tasks. It lets teams ship faster by abstracting away infrastructure complexity.
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