2026-02-13

harness-engineering-openai - Building Software with 0 Lines of Human-Written Code

OpenAI's Codex team built a real internal product (hundreds of daily users, external alpha testers) with a team of 3–7 engineers writing zero lines of code by hand. Everything — app logic, tests, CI, docs, observability — written by Codex. Result: ~1M lines of code, ~1,500 PRs in 5 months, 3.5 PRs/engineer/day, estimated 1/10th the time to build manually.

Key lessons: (1) AGENTS.md should be a 100-line map, not a 1,000-page manual — point to a structured docs/ directory as system of record; (2) anything not in the repo doesn't exist for the agent — Slack discussions, Google Docs, people's heads are all inaccessible; (3) make the app itself legible to the agent (Chrome DevTools Protocol, per-worktree observability with LogQL/PromQL); (4) strict architecture enforced by custom linters is the prerequisite for agent velocity, not something you add later; (5) continuous "garbage collection" via background Codex cleanup agents beats weekly "AI slop" cleanup sessions (they tried Friday cleanup, it didn't scale).

Key quote: "Building software still demands discipline, but the discipline shows up more in the scaffolding rather than the code."

react-pdf-skill - Professional PDF Generation for Claude Code

Claude Code skill for generating high-quality PDFs using React-PDF by Alexey Taktarov (@mlfrg). Uses declarative React components instead of imperative Python libraries. Features: Flexbox/Grid layout (Yoga engine), Knuth-Plass typography, SVG primitives, Google Fonts (~65 bundled), smart page breaks, emoji support. Install: npx skills add molefrog/skills --skill react-pdf. AI-friendly: declarative > imperative for LLMs.