docker-build-cache-debug

What problem does it solve?

Docker build cache can cause outdated code to run in deployed containers even after source files are modified, leading to hard-to-trace bugs where builds report success but the running application does not reflect recent changes.

Core Features & Use Cases

• Staleness Detection: Step-by-step commands to compare Docker image creation timestamps with the latest git commit timestamps to confirm if an image is outdated.
• Frontend Bundle Validation: Methods to grep production SPA bundles for recently added user-visible strings to catch stale frontend builds.
• Fix & Prevention Workflow: Guided steps for forced no-cache rebuilds, replacing stale container instances, and best practices to avoid cache-related stale code issues in future deployments.
• Use Case: Ideal for DevOps engineers and full-stack developers debugging why production containers do not show new features or bug fixes after code commits, or frontend teams missing newly added UI elements in deployed SPAs.

Quick Start

Use this skill to diagnose and resolve stale Docker container issues by following the provided debug, rebuild, and validation workflow.