zero2codex
OpenAI Codex workflow course

Course goal: ship your personal brand site

Build a personal brand site with Codex

Keep improving one project from an empty folder to a responsive one-page site with an introduction, projects, and contact details. Every lesson adds a visible result or a check toward that finish line.

Curriculum

Personal brand site build path

01

Start With Codex

Set up Codex and build the hero section of your personal brand site.

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00｜Install And Open CodexInstall the desktop app, sign in, open the site project folder, and send a safe first message.What Codex Is ForBuild the first version of your site with a name, introduction, projects, contact details, and one working button.Choose A Codex SurfaceEdit the site's Projects button locally, then verify its text and behavior in a browser.Your First Useful PromptTurn “add an About section” into a concrete request with content, constraints, and browser checks.
04

Ship Verified Changes

Test the site, check desktop and mobile views, and review the final diff.

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Test The ChangeAdd focused checks for the site's theme and navigation without breaking earlier work.Browser VerificationOpen the real site and check content, navigation, and layout at desktop and mobile widths.Review Before AcceptingReview the site's full diff, test evidence, and any remaining visual or behavior risks.
9 minReady

Review Before Accepting

Accept Codex output only after checking the diff and verification evidence.

diff reviewbehavioral risktest gaps

Plain-language explanation

Reviewing before accepting means you read the diff like a teammate's pull request. Look first at behavior, then tests, then maintainability.

Codex can help summarize its own diff, but you still decide whether the changes are appropriate and small enough.

Why it matters

Tests can pass while the code still changes too much, hides risk, or violates your project style.

Common beginner mistake

A common mistake is accepting every file Codex touched just because the final command passed.

Step-by-step

  1. Ask Codex to summarize why each changed file was touched.
  2. Scan for unrelated changes or surprising deletions.
  3. Check whether tests match the requested behavior.
  4. Ask follow-up questions before accepting unclear code.

Good prompt

Codex, review your uncommitted diff before I accept it. Explain each changed file, call out behavior risks, list tests run, and mention any checks you could not run. Do not modify files during the review.

Try this

After a small Codex change, ask for a diff summary and write one risk you want to inspect yourself.

Completion checklist

  • The summary explains why each changed file was touched.
  • Unrun checks or residual risks are called out plainly.

Sources

08

Finish And Deliver The Site

Polish independent tasks in parallel, then complete one final acceptance review.

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Complete The Site GoalTurn the finished personal site into one measurable goal with content, layout, interaction, and evidence checks.Polish Copy And Accessibility In ParallelUse isolated worktrees only when copy polish and accessibility review can avoid editing the same lines.Run The Final Three ReviewsRun separate content, link, and accessibility reviews, then compare all evidence against the same launch checklist.

Practice lab

Copyable Codex prompts

Plan before coding

Codex, inspect the relevant files first, then propose a plan. Do not edit until the plan names tests and verification steps.

Verification checklist

  • Relevant files are named before edits begin.
  • The plan includes tests and verification commands.

Verify a UI change

Codex, start the dev server, open the route in the browser, check desktop and mobile layouts, then report the exact evidence.

Verification checklist

  • Desktop and mobile states are checked in the browser.
  • The final note includes exact evidence.

Review focused risk

Codex, review the uncommitted diff. Focus on behavioral regressions, missing tests, and accessibility issues. Do not modify files.

Verification checklist

  • Findings lead with severity and file references.
  • Unchanged files are left untouched.
Every good Codex request says what to change, what to preserve, and how to prove it worked.

Reference

Codex concepts to keep nearby