Build a Full Backend with OpenAI Codex and Xano

In this walkthrough, we use OpenAI Codex alongside the Xano CLI and Developer MCP to build a loan origination backend — including database tables, APIs, business logic, and user activity logging from a single prompt — then generate a matching frontend using OpenAI Codex's full backend context.

What's covered

• Installing the Xano CLI and XanoScript Language Server
• Connecting the Developer MCP so Codex can validate XanoScript as it builds
• Authenticating and pulling your workspace locally
• Prompting Codex to build a loan origination backend from scratch
• Pushing to a Xano sandbox for validation before production
• Reviewing changes in a Git-style diff view
• Publishing to a live branch and promoting to production
• Using Codex to generate a frontend with full backend context already loaded

The Developer MCP lets OpenAI Codex write and validate XanoScript as it works, so the backend it generates is production-ready — not a throwaway prototype. Once the APIs and business logic are live, OpenAI Codex already has full context to build a matching frontend.

Resources

• Developer MCP docs: https://docs.xano.com/developer-mcp/get-started
• Xano CLI docs: https://docs.xano.com/xano-cli/get-started