OpenAI Codex: Build Apps That Work For You 24/7
Greg Isenberg · 2026-06-04
💡 Quick Take
1. Invoke Codex Sites as a plugin.
2. Ask Codex Sites to use realistic sample data.
3. Use "Save for review, do not deploy" to build real products, not just homepages.
4. Leverage Codex plugins for interactive and interesting sites.
5. Integrate Game Studio plugin for buzz generation and user acquisition.
6. Add persistent storage (memory) to save data between visits.
7. Request Codex Sites to show the data model and required actions before coding.
8. Implement "Safe Actions" for automated app modifications.
9. Create Codex Skills for reusable instruction manuals to guide the app's operation.
10. Use "Save gates" (checkpoints) before publishing live URLs.
11. Prompt Codex Sites to publish websites.
12. Build autonomous products that update and improve themselves.
📊 Detailed Explanation
1. Invoke Codex Sites as a plugin: To get started with Codex Sites, you need to explicitly tell Codex to use it by invoking it as a plugin. This is the first step to unlock its site-building capabilities.
2. Ask Codex Sites to use realistic sample data: When prompting Codex Sites to build something, it's beneficial to ask it to use realistic sample data. This helps in creating a more functional and representative initial version of your app or site.
3. Use "Save for review, do not deploy" to build real products, not just homepages: This is a crucial tip for building actual product services rather than just static homepages. By saving for review and not deploying immediately, you allow Codex Sites to work on the underlying structure and functionality, enabling autonomous editing and ongoing development, which is the ultimate goal for building dynamic products.
4. Leverage Codex plugins for interactive and interesting sites: The transcript highlights that there's a whole section of plugins within Codex that can significantly enhance your sites. Think of integrating tools like Figma, Canva, HeyGen for avatars, or Remotion to make your site ideas more interactive and engaging.
5. Integrate Game Studio plugin for buzz generation and user acquisition: The Game Studio plugin is presented as an underrated tool. The idea is to build small, fun games (like a Paper Boy competitor) that can generate buzz around your core product. These mini-games can attract users, who can then be brought into your main application or service, especially useful for consumer-facing apps.
6. Add persistent storage (memory) to save data between visits: For any piece of software to be truly productive, it needs to remember things. Prompting Codex Sites to add persistent storage ensures that data saved during visits remains saved, transforming a demo into a functional application.
7. Request Codex Sites to show the data model and required actions before coding: Before it starts coding, it's a good practice to ask Codex Sites to first present the data model and outline the actions the app will need. This provides clarity on what the app will store and what operations it can perform, and it's especially helpful for non-technical users to understand the structure.
8. Implement "Safe Actions" for automated app modifications: Safe Actions are a key unlock. They allow for approved buttons or commands that can automate adding, removing, or editing parts of your app. This means you, as the human, don't have to do every single manual update. You can even trigger these actions from other chats within Codex, directly impacting your live application.
9. Create Codex Skills for reusable instruction manuals to guide the app's operation: Skills act as reusable instruction manuals for Codex. By creating skills, you teach Codex how to operate your app later on. This is essential for enabling Safe Actions and ensuring the app can be managed and updated effectively, making it a valuable part of the autonomous development process.
10. Use "Save gates" (checkpoints) before publishing live URLs: Just like checkpoints in a video game, it's wise to save your progress before publishing a live URL. This involves asking Codex Sites to save the current state for review, confirming build status, storage choices, and access settings without actually deploying it to the public internet.
11. Prompt Codex Sites to publish websites: Once you're ready, you can prompt Codex Sites to publish your website. While currently, this might result in a temporary URL, the expectation is that this will evolve to support custom domains, making these published sites more accessible.
12. Build autonomous products that update and improve themselves: The overarching dream and a core message is the ability to build products that can update and improve autonomously. This involves creating agents that can automatically modify products based on various criteria, leading to valuable and self-sustaining applications. Codex Sites is positioned as a tool to achieve this "dream state" of autonomous product building.
🎯 Tech Expert Opinion
Alright, so diving into Codex Sites is seriously exciting, and this transcript nails a lot of the core concepts that are going to define the next wave of AI-powered development. The comparison to Replit and Lovable is spot on – those are fantastic for quick, self-contained projects or single-prompt deployments. But Codex Sites? It's a whole different ballgame. It's about building *living* applications that can evolve on their own, and that's where the real magic happens.
The emphasis on "autonomous product building" isn't just buzzwords; it's the future. We're moving beyond static websites to dynamic, self-updating systems. The idea of agents making changes automatically based on data or triggers is huge. This is especially relevant for startups or individuals looking to build products without massive engineering teams. Think about it: an AI agent that monitors customer feedback and automatically updates features, or a content platform that generates new articles based on trending topics. Codex Sites is laying the groundwork for this.
The "Safe Actions" and "Skills" are the secret sauce here. They're essentially creating a robust API and control layer for AI agents. This is critical because it prevents the AI from going rogue and ensures that modifications are controlled and intentional. For anyone who's worked with AI models, you know the importance of guardrails. Safe Actions are those guardrails, and Skills are the instruction manuals that tell the AI *how* to use them. This is a massive step up from just asking an AI to "build me a website." It's about building a system that can be managed and interacted with by AI over time.
The mention of missing databases, payments, and email sending is also a key insight. This tells us that while Codex Sites is powerful for the core application logic and UI, it's not a full-stack platform *yet*. This is where integrations and potentially a hybrid approach come into play. We'll likely see a surge in tools and services that bridge these gaps, allowing Codex Sites to leverage external services for these functionalities. Convex, as mentioned, is a promising direction for real-time data and databases within this ecosystem.
The "Save gates" or checkpointing mechanism is a smart defensive strategy. In the world of AI development, especially with autonomous agents, having rollback points is essential. It ensures that you can revert to a stable version if an autonomous update goes awry. This is a best practice that will become even more critical as these systems become more complex.
My prediction? Codex Sites is going to become a cornerstone for building what I call "AI-native applications." These aren't just apps with AI features; they are apps *built by* and *operated by* AI. The ability to have an app that updates itself, learns, and adapts without constant human intervention is going to revolutionize how we think about software development and product management. The current limitations – like the temporary URLs – are just growing pains. The underlying architecture and the concepts of autonomous operation, controlled actions, and reusable skills are incredibly powerful and signal a major shift in the tech landscape. It's not just about building an app; it's about building an evolving entity.
Kanal: Greg Isenberg