This book teaches an APM engineer how to monitor software services and applications in real time, including collecting detailed performance data on the response time for incoming requests, database queries, cache calls, and external HTTP requests. The book helps readers to explore the architecture and components of the Elastic APM stack. It also teaches you how to architect, deploy, and configure the Elastic APM stack to meet your specific requirements.The book focuses on monitoring and observability for applications and infrastructures built with Containers and Kubernetes. The book helps you configure APM capabilities like synthetic transaction and real-user transaction monitoring, integration with open-source tools like Prometheus, and data collection and processing using Logstash. Additionally, the book discusses how to use the Kibana dashboard features provided by Elastic APM in conjunction with alerting and dashboards to analyze the application's performance.Finally, the book teaches Site Reliability Engineers (SREs) how to meet service-level objectives through indicators such as availability, latency, quality, and saturation.TABLE OF CONTENTS1. Introduction to Application Observability2. Elastic Observability Features3. Elastic Observability Deployment Architecture4. Deployment of the Elastic Observability Platform5. Use Case. Observability for a Containerized Java Application6. Use Case. Observability for a Kubernetes-based Application7. Observability for a .Net Core Application8. Elastic Observability. User Experience, Uptime, and Synthetic Monitoring9. Logstash Pipelines in Elastic Observability10. Prometheus Integration with the Elastic Observability Platform11. Machine Learning, Alerting, and Dashboards