I have personally taken this approach with web dev, granted I'm a very senior developer. First, develop features, then ask a larger/smarter model (o3, o3-pro, gemini-2.5 pro) to analyze the entire codebase (in sections if needed) and surface every security issue, vulnerability, attack vector, etc. I then pass that back to agents to execute refactors that clean up the code. Repeat until all your keys are in the proper place, all your calls are secured, all your endpoints are locked down, all your db calls are sanitized, etc etc etc.
Now, this should have been done PRIOR to release and would have only taken a few more days (depending on app complexity and the skill of the developer).
[1]: https://arxiv.org/html/2505.15216 - "OpenAI Codex CLI: o3-high, OpenAI Codex CLI: o4-mini, and Claude Code are more capable at defense, achieving higher Patch scores of 90%, 90%, and 87.5%"