Microservices architectures transformed modern software engineering by enabling modularity, scalability, and independent service deployment. By decomposing monolithic systems into smaller services, organizations achieved greater development flexibility and operational agility. However, as these architectures expanded, a new form of systemic complexity emerged. Complexity did not disappear; rather, it shifted from internal application logic to inter-service coordination, distributed communication, and emergent system behavior. This paper examines the limitations of traditional microservices management approaches in large-scale distributed environments. Conventional observability tools such as logging, metrics, and distributed tracing provide visibility into execution flows but often fail to capture whether the overall system behavior aligns with intended operational outcomes. As distributed architectures grow increasingly interconnected, understanding system behavior requires abstractions that extend beyond individual service interactions. To address this challenge, the paper introduces the concept of Behavior-Centric Architecture, a higher-level systems abstraction that models distributed systems around meaningful operational behaviors rather than isolated services. In this model, behaviors represent end-to-end outcomes—such as order completion, payment processing, or user onboarding—that emerge from coordinated interactions across multiple services. The study explores how behavior-centric models improve observability, coordination, and operational governance in complex distributed systems. It further examines the implications of behavioral tracking, drift detection, and emergent behavior management for large-scale microservices environments. By shifting the architectural focus from service execution to behavioral coherence, this work proposes a new framework for understanding and governing distributed software systems whose complexity increasingly arises from interaction rather than implementation.
Ilker Kanatli (Sat,) studied this question.