Datadog

Datadog is a cloud monitoring and analytics platform that provides full-stack observability by unifying infrastructure metrics, application performance monitoring, log management, and security monitoring in a single platform. It collects data from servers, containers, databases, and applications through agents and integrations, presenting everything in customizable dashboards with alerting capabilities.

The application performance monitoring traces requests across distributed systems, showing how long each service, database query, and external API call takes within a request lifecycle. This is essential for diagnosing bottlenecks in microservices architectures where a slow response might originate from any of dozens of interconnected services. Log management allows correlating log entries with specific traces and infrastructure events.

For web development, Datadog matters because production applications require observability to operate reliably. When a page loads slowly or an API endpoint returns errors, distributed tracing can pinpoint whether the problem is in application code, a database query, a third-party API, or infrastructure capacity. Its Real User Monitoring tracks actual browser performance metrics from end users. The tradeoff is cost, as per-host and per-feature pricing adds up at scale.