Docker Roadmap
Mastering Containerization and Modern Development Workflows
Your Journey at a Glance
💡 How to use this roadmap
Work through each phase in order. Click on a skill to expand it — you'll find a description and curated resources. Don't rush; understanding beats speed. Complete one phase before moving to the next.
Foundations & The Engine
Understand what a container actually is (Hint: It's just a process). Learn the core architecture of Docker.
Advanced Images & Dockerfiles
Build high-performance, secure images. Master the art of the multi-stage build and layer optimization.
Networking & Persistence
Connecting containers and keeping data alive. Master Docker networking types and storage drivers.
Orchestration & Security
Moving to production. Master Docker Compose for multi-container apps and learn to secure your containers.
Roadmap Complete!
You now have the foundations of a production-ready Java engineer. Apply by building real projects.
Architect a High-Availability Microservices Stack
Design and containerize a full-stack application including an API, a background worker, a database, and a cache, all managed via Docker with production-ready security.
What you'll build
- Optimized multi-stage builds for all services using Distroless images
- Automated health checks and self-healing configurations in Docker Compose
- Secure secret management using environment file encryption and non-root users
- Custom bridge networks for isolation with internal DNS service discovery
- Resource-constrained environment (CPU/RAM limits) to prevent noisy neighbors
- Persistent analytics volume with automated backup scripts
Tech stack
Key highlights
- ✦Demonstrates mastery of professional image building and orchestration
- ✦Focuses on production-grade security and resource management
- ✦Includes real-world networking and persistence patterns
Real-World Scenarios
Practical case studies where these skills are applied.
01The 2GB Hello-World: Image Bloat
The Problem
A simple Node.js application resulted in a 2.2GB Docker image, leading to slow CI/CD pipelines and high storage costs.
The Solution
Implemented multi-stage builds and switched to Alpine/Distroless base images. Optimized layer caching by ordering commands from least to most frequent changes.
Outcome
02Ephemeral Data Loss: Missing Volumes
The Problem
A database container was restarted during an update, and all production data was wiped because it was stored in the container's writable layer.
The Solution
Migrated to 'Named Volumes' and implemented a backup sidecar. Configured persistent storage with correct mount points for the database data directory.
Outcome
03Zombie Processes & Signal Handling
The Problem
Containers were taking 10 seconds to stop and were leaving orphan processes behind, causing memory leaks on the host machine.
The Solution
Switched to using a proper init process (`tini`) and ensured the application correctly handles SIGTERM. Wrapped the execution in an 'exec' form instead of 'shell' form.
Outcome