The gradual nature of architectural drift, with its incremental changes that often go unnoticed or don’t immediately “break the system”, often leads developers to overlook or dismiss its significance.

However, akin to the insidious spread of rust or rot, architectural drift gradually deteriorates the original composition and structure of an application, having a direct technical, business and cost impact.

(1) It paves the way for future complications.

When we introduce unaccounted-for architectural decisions, we open the doors to a range of issues:

• Security Risks: Introducing unexpected resources or deploying them incorrectly can create security vulnerabilities, particularly if these changes escape the notice of the security team.

• Delayed Feature Implementation: Deviating from the intended architectural blueprint complicates the integration of new features, potentially impairing the system’s ability to adapt to evolving business demands.

• Resource Misconfigurations: The increasing complexity resulting from architectural drift amplifies the likelihood of misconfigurations, leading to deployment issues. This is exacerbated in environments where multiple teams deploy to a shared cloud, raising the risk of resource conflicts or redundancies.

• Escalating Costs: Incremental enhancements to the architecture can cumulatively inflate cloud expenditure significantly.

• Unmonitored Resources: Departure from the planned architecture might render existing management and maintenance protocols ineffective, leaving behind unpatched and potentially vulnerable resources concealed within the architecture.

• Higher Engineering Overhead: An unplanned architecture demands more maintenance and resources, particularly for sub-optimal choices or solutions not aligned with the architectural roadmap. This complexity not only increases the costs associated with system upkeep but also prolongs the onboarding and offboarding processes, given the undocumented nature of system modifications.

(2) It highlights issues with the original architecture.

Architectural drift may not always be bad news! Drift that occurs in response to new requirements — which could not be satisfied within the confines of the system’s existing architecture — can highlight previously overlooked but crucial design elements.

It’s imperative to understand if the original architecture was inherently flawed so teams can take appropriate steps to address the problems.

Ignoring architectural drift is akin to turning a blind eye to the slow but sure erosion of a system’s integrity and functionality. Over time, the accumulating gaps between the actual architecture and the intended architecture can lead to decreased maintainability, reduced system performance, and increased complexity.

What's Next

For more about system architecture drift check out these next articles:

• 101 on Architectural Technical Debt
• [Part 1] Delving into Architectural Drift
• [Part 2] Architectural Drift in Real Life Systems
• [Part 4] Effective Measures to Control System Architecture Drift

Thank you for reading! 💜