Production systems

The use cases in this collection are useful when Codex is working in a repo that already has history, tests, owners, and production constraints. Codex is particularly good at navigating complex codebases, including sprawling monorepos with lots of different services and dependencies. If you're working on a production system, get familiar with these use cases to understand how Codex can help you.

Start with a codebase tour

Use Codex to get familiar with a complex codebase, which is especially useful when onboarding onto a repo for production software.

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Understand large codebases

Use Codex to map unfamiliar codebases, explain different modules and data flow, and point...

Engineering Analysis](https://developers.openai.com/codex/use-cases/codebase-onboarding)

Modernize the codebase

Leverage Codex to plan tech stack migrations, upgrade your integration to the latest models if applicable, and refactor the codebase to improve readability and maintainability.

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Upgrade your API integration

Use Codex to update your existing OpenAI API integration to the latest recommended models...

Evaluation Engineering](https://developers.openai.com/codex/use-cases/api-integration-migrations)[

Refactor your codebase

Use Codex to remove dead code, untangle large files, collapse duplicated logic, and...

Engineering Code](https://developers.openai.com/codex/use-cases/refactor-your-codebase)[

Run code migrations

Use Codex to map a legacy system to a new stack, land the move in milestones, and validate...

Engineering Code](https://developers.openai.com/codex/use-cases/code-migrations)

Codify repeatable work

Ask Codex to turn repo-specific workflows or checklists into a skill, so that all repo contributors can benefit from a standardized process.

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Save workflows as skills

Turn a working Codex thread, review rules, test commands, release checklists, design...

Engineering Workflow](https://developers.openai.com/codex/use-cases/reusable-codex-skills)

Maintain system health

Let Codex pick up feature requests and bug fixes automatically by using it from Slack and connecting it to your alerting, issue tracking, and daily bug sweeps.

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Kick off coding tasks from Slack

Mention @Codex in Slack to start a task tied to the right repo and environment, then...

Integrations Workflow](https://developers.openai.com/codex/use-cases/slack-coding-tasks)[

Automate bug triage

Ask Codex to check recent alerts, issues, failed checks, logs, and chat reports, tune the...

Automation Quality](https://developers.openai.com/codex/use-cases/automation-bug-triage)

Avoid the review bottleneck

Use Codex to automatically review PRs and run focused QA passes on critical flows, so you can catch issues quickly and ship updates confidently.

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Codex code review for GitHub pull requests

Use Codex code review in GitHub to automatically surface regressions, missing tests, and...

Integrations Workflow](https://developers.openai.com/codex/use-cases/github-code-reviews)[

QA your app with Computer Use

Use Computer Use to exercise key flows, catch issues, and finish with a bug report.

Automation Quality](https://developers.openai.com/codex/use-cases/qa-your-app-with-computer-use)