The Simian Army is a suite of tools developed by Netflix to improve the reliability and resilience of its cloud-based applications. The most well-known tool is Chaos Monkey, which randomly terminates instances to test system resilience. The goal is to identify weaknesses in the system, ensuring that applications can handle failures gracefully and maintain uptime. This practice is a key component of chaos engineering, which focuses on improving system reliability through controlled experiments that expose potential issues. Other tools in the Simian Army include:

  • Latency Monkey: Introduces latency to simulate slow responses.
  • Conformity Monkey: Ensures services adhere to best practices and architecture guidelines.
  • Chaos Gorilla: Simulates an entire availability zone failure.
  • Doctor Monkey: Monitors instances and alerts when issues are detected.

Together, these tools help organizations proactively identify weaknesses and improve the overall reliability of their systems through chaos engineering principles.