Tree Shaking

A canary release is a deployment strategy where a new version is gradually rolled out to a small subset of users before reaching the full audience. Automated monitoring compares error rates, latency, and key metrics between the canary and the stable version. If the canary performs well, traffic is incrementally shifted; if anomalies are detected, the release is automatically rolled back, minimizing the blast radius of potential issues.

Auto-scaling is the ability of a system to automatically adjust the number of running instances or allocated resources based on current demand. When traffic spikes, new instances are provisioned; when demand drops, excess resources are released to save costs. Cloud platforms like AWS, GCP, and Azure offer auto-scaling groups with configurable policies based on CPU usage, request count, queue depth, or custom metrics.

A cron job is a time-based task scheduler originating from Unix systems that runs commands or scripts at specified intervals. The schedule is defined using a cron expression with five fields representing minute, hour, day, month, and weekday. Cron jobs are fundamental for automations like database backups, log rotation, report generation, and periodic data synchronization.

Docker is a platform that packages applications and their dependencies into lightweight, portable containers that run consistently across any environment. A Dockerfile defines the build steps, and images can be shared via registries like Docker Hub. Containers are essential for automation because they guarantee that code behaves the same in CI pipelines, staging, and production, eliminating "works on my machine" issues.

Infinite scroll is a UX pattern where new content loads automatically as the user scrolls toward the bottom of the page, eliminating traditional pagination. It's commonly used in social media feeds and content discovery interfaces. While it increases engagement and feels seamless, it can hurt performance without virtualization and makes it difficult for users to reach footer content or bookmark specific positions.

Drag and drop is an interaction pattern that lets users move, reorder, or transfer UI elements by clicking (or touching), holding, and dragging them to a new position. It's used for file uploads, kanban boards, sortable lists, and layout builders. The HTML Drag and Drop API provides native browser support, while libraries like dnd-kit and react-beautiful-dnd offer more polished, accessible, and touch-friendly implementations.