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Week 12: Codex Themes, 49 Agent Logos, and a Newsletter That Writes Itself

What I Shipped

  • Built a full Codex (OpenAI) theme provider for tinte — reverse-engineered the desktop app’s asar bundle to extract 55 valid Shiki theme IDs
  • Added 29 tech logo components to the Elements registry (Algolia, Convex, PostHog, Nvidia, Ollama, LangChain, and more) — all theme-adaptive for dark/light mode
  • Shipped an agent-stack dashboard with 49 AI services, competition rankings, and OG images
  • Built a full newsletter system for railly.dev — subscribe API, broadcast send, archive pages, all auto-generated from daily logs using the Resend CLI
  • Got accepted into the Codex Ambassador program (now both v0 + Codex Ambassador)
  • Pitched and got approved for a v0 workshop series with Vercel for LATAM

TIL

OpenAI’s Codex desktop app validates theme imports against exactly 55 built-in Shiki codeThemeId values. Custom slugs like “one-hunter” fail silently — you have to hardcode a valid ID like light-plus or dark-plus and let the colors do the work. Found this by unpacking the Electron asar bundle and reading their Zod schema.

Worth Checking Out

Resend CLI - 53 commands for managing emails, domains, contacts, broadcasts, and webhooks from your terminal. Ships with both human-friendly (spinners, tables) and agent-friendly (--json, --quiet) modes. Natural language scheduling built in.

One Thought

The best content pipeline is one where writing is a byproduct of work you already do. I built this newsletter so it auto-extracts from my daily logs — zero extra writing effort. If your workflow doesn’t produce shareable artifacts, you’re doing invisible work.