What's the difference between decision engine and rules engine, and when should you use each?

A Rules Engine handles static, predefined conditions. It uses if-then-else logic to enforce fixed policies. This ensures auditable compliance with governance standards like RAILS.md and append-only outbox patterns.

A Decision Engine evaluates complex, often dynamic logic. It might use ML or heuristics to produce outcomes. It adapts to changing conditions instead of relying on static rules.

Use a Rules Engine for strict, auditable compliance with fixed policies. This includes enforcing governance via RAILS.md and append-only outbox patterns.

Use a Decision Engine for adaptive, data-driven decisions. You need this when evaluating dynamic logic is required.