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HomeLabChallenges

Challenge Labs

Tackle real-world coding challenges. Solve problems, earn points, and sharpen your skills.

1645

Total Points

Intermediate⏱ 45 min150 pts⭐ Premium

Secure a Linux Server (Hardening Checklist)

A compromised staging server needs to be hardened. Identify and fix misconfigurations: world-writable files, weak SSH config, exposed services, and missing firewall rules.

Linux
Security
SSH
Hardening
Premium
Beginner⏱ 30 min100 pts⭐ Premium

Debug a Broken systemd Service

A critical background service has failed to start after a system update. Use journalctl, systemctl, and config inspection to diagnose and fix it.

Linux
systemd
Debugging
Logs
Premium
Intermediate⏱ 40 min200 pts⭐ Premium

Optimise a Bloated Docker Image

A production Docker image is 1.4 GB. Reduce it to under 200 MB without breaking functionality. Use multi-stage builds, Alpine base, and layer caching best practices.

Docker
Optimisation
Multi-stage Build
Alpine
Premium
Beginner⏱ 30 min120 pts⭐ Premium

Fix a Broken Docker Compose Stack

A docker-compose.yml with an Nginx reverse proxy, Node.js API, and PostgreSQL database fails to start. Find and fix all 5 intentional bugs.

Docker
Docker Compose
Debugging
Networking
Premium
Intermediate⏱ 35 min175 pts⭐ Premium

Kubernetes: Diagnose and Fix a CrashLoopBackOff Pod

A microservice Deployment is stuck in CrashLoopBackOff. Use kubectl logs, describe, and events to identify the root cause and apply a fix.

Kubernetes
Debugging
CrashLoopBackOff
kubectl
Premium
Advanced⏱ 45 min250 pts⭐ Premium

Write a Kubernetes RBAC Policy from Scratch

The CI/CD pipeline service account needs precise permissions. Write a Role and RoleBinding that grants only the minimum required permissions (principle of least privilege).

Kubernetes
RBAC
Security
ServiceAccount
Premium
Advanced⏱ 50 min275 pts⭐ Premium

Azure: Secure Storage Account with Managed Identity

Remove the hardcoded storage account key from an application. Replace it with Azure Managed Identity + RBAC so the app can access Blob Storage without any credentials in code.

Azure
Security
Managed Identity
RBAC
Storage
Premium
Intermediate⏱ 40 min175 pts⭐ Premium

Nginx: Fix an SSL Misconfiguration

An Nginx server is failing SSL handshakes and browser security scanners report weak cipher suites, missing HSTS, and an expired certificate. Fix all issues to achieve an A+ SSL Labs rating.

Nginx
SSL
TLS
Security Headers
Web Server
Premium
Intermediate⏱ 45 min200 pts⭐ Premium

Build a Dockerfile for a Production Web App

Containerise a Python Flask API for production: multi-stage build, non-root user, health check endpoint, secrets via runtime env vars, and minimal final image under 120 MB.

Docker
Python
Flask
Web App
Production
Premium