30+ OpenAI Codex CLI Tips & Tricks (v0.30–0.39 Edition)

The Complete Guide for Creative Professionals . Codex-CLI version 0.39 (September 2025) [update 0.44]

You probably know about my 100 Codex CLI tips that went viral last month.

Half of them are outdated now.

Versions 0.30 through 0.39 changed how Codex works at its core. These new features are incredibly impactful: code that fixes itself, memory that stays between sessions, and workflows that run without you watching.

Most developers don't know these exist. They're still using old methods that take hours instead of minutes.

This guide shows you 30 hidden features from the latest updates. From simple tricks beginners can use today to advanced techniques that replace expensive tools.

Each tip tells you exactly which version added it and how to use it.

The difference is stark. Without these techniques, Codex is just another AI assistant. With them, it becomes a development platform that works while you sleep.

Your competitors are already using these. Are you?