Use Codex to build a formal model of your authorization rules before coding them
A team used Codex to build an Alloy model verifying GoodMem's authorization model, then wrote the code from it. Hours of red-teaming with another model and attacker source access failed to find a privilege escalation.
Source
svcrunch on Hacker News · 2026-10-23
Written in our own words. Credit to the original author. Link checked 2026-10-23.
What they did
A team used Codex to build an Alloy model verifying GoodMem's authorization model, then wrote the code from it. Hours of red-teaming with another model and attacker source access failed to find a privilege escalation.
Result (as claimed)
Formal verification became practical for a small team.
Tools they used
Cost: OpenAI Codex: free plan, paid from $8/mo. Checked 2026-10-14.
Set it up
Pick a contained repo or task
Start on a branch or side project where mistakes are cheap.
Install and configure
Set up OpenAI Codex, Alloy. Read what it can run on your machine and limit permissions where possible.
Run it on a real task
Give it a well-scoped issue and let it work. Review the diff like any pull request.
Add guardrails
Keep tests and CI in the loop, and never let an agent push to main or touch production secrets unattended.
Copy the full setup prompt
Paste into your agent and it will walk you through the setup, asking before anything that sends, posts or spends.
You are helping me set up this AI use case end to end in Claude Code. Goal: Use Codex to build a formal model of your authorization rules before coding them What the original author did: A team used Codex to build an Alloy model verifying GoodMem's authorization model, then wrote the code from it. Hours of red-teaming with another model and attacker source access failed to find a privilege escalation. Reported result (as claimed by the author): Formal verification became practical for a small team. Source: https://news.ycombinator.com/item?id=50204788 Tools they used: OpenAI Codex, Alloy Category: Dev & ops Please: 1. Ask me 3 short questions about my situation (accounts I have, budget, what I want the output to look like). 2. Propose a step-by-step plan using these tools or cheaper alternatives, with the time and cost of each step. Use official pricing pages; say "check pricing" if unsure. 3. Then do the setup with me one step at a time, waiting for my OK before anything that sends messages, posts publicly, spends money or deletes data. 4. Finish with a checklist to run it again next time.
You are helping me set up this AI use case end to end in Codex. Goal: Use Codex to build a formal model of your authorization rules before coding them What the original author did: A team used Codex to build an Alloy model verifying GoodMem's authorization model, then wrote the code from it. Hours of red-teaming with another model and attacker source access failed to find a privilege escalation. Reported result (as claimed by the author): Formal verification became practical for a small team. Source: https://news.ycombinator.com/item?id=50204788 Tools they used: OpenAI Codex, Alloy Category: Dev & ops Please: 1. Ask me 3 short questions about my situation (accounts I have, budget, what I want the output to look like). 2. Propose a step-by-step plan using these tools or cheaper alternatives, with the time and cost of each step. Use official pricing pages; say "check pricing" if unsure. 3. Then do the setup with me one step at a time, waiting for my OK before anything that sends messages, posts publicly, spends money or deletes data. 4. Finish with a checklist to run it again next time.
You are helping me set up this AI use case end to end in Grok Bot. Goal: Use Codex to build a formal model of your authorization rules before coding them What the original author did: A team used Codex to build an Alloy model verifying GoodMem's authorization model, then wrote the code from it. Hours of red-teaming with another model and attacker source access failed to find a privilege escalation. Reported result (as claimed by the author): Formal verification became practical for a small team. Source: https://news.ycombinator.com/item?id=50204788 Tools they used: OpenAI Codex, Alloy Category: Dev & ops Please: 1. Ask me 3 short questions about my situation (accounts I have, budget, what I want the output to look like). 2. Propose a step-by-step plan using these tools or cheaper alternatives, with the time and cost of each step. Use official pricing pages; say "check pricing" if unsure. 3. Then do the setup with me one step at a time, waiting for my OK before anything that sends messages, posts publicly, spends money or deletes data. 4. Finish with a checklist to run it again next time.
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