All patterns

Architecture pattern

Decision sidecar

A typed judgment service sits beside ordinary code; code owns effects and safety boundaries.

Plausible

What the pattern does

A typed judgment service sits beside ordinary code; code owns effects and safety boundaries.

Caveat

The extra network hop must beat a local rule or classifier.

Patterns are recurring shapes observed across the collected material. A repeated shape is evidence that developers converge on it, not evidence that it performs well in production.

Sources

Limitations

  • The extra network hop must beat a local rule or classifier.

Where this pattern appears

Record
pattern:decision-sidecar
Canonical
/patterns/decision-sidecar
Last verified
2026-09-18