# Unix Philosophy in Modern Apps
AI-readable version of this post.
Path: /classics/unix-philosophy
Category: Classics
Date: 1987-06-01
Author: Systems Notes
Reading time: 1 min
Description: Small focused parts with composable interfaces still win.
## Do one thing well

Clear module boundaries make systems easier to test and evolve.

## Compose with interfaces

Stable contracts reduce coupling and improve replaceability.

## Keep outputs predictable

Deterministic behavior is easier to debug and monitor.