Mihai Marinescu

AI-powered documentation platform out of Y Combinator. Four years as one of its primary authors — 468 merged PRs across the React/Next.js front end and the Node + PostgreSQL backend.

• Cut keystroke latency on large docs from ~1.4s — browser blocking and crashing — to ~100ms, no crashes. On a profiled doc: 245ms → 56ms, and ~1,531 re-renders per keystroke down to 1–2.
• Re-engineered the merge/diff/conflict engine behind Git-style document branching: node-id-aligned three-way merge, LCS minimal diffs, an ~815-line conflict-diff builder — and a cross-move conflict that silently deleted documents, fixed at the root. The foundation was a teammate's; the engine on top is ~90% mine by git blame.
• Sole author of the AI authoring agent — a tool-calling agent that generates and edits blocks inside documents — plus the agentic generator behind docs.new and the AI surface around it (summaries, ask-AI search, feedback).
• Authored rich-text blocks and normalizers inside Slate/Plate — a new tables implementation, code editor, inline LaTeX, reusable content, workflows — and the node-model and cursor bugs that come with them.
• Built and grew an interactive API-docs sub-product over three years: OpenAPI/Swagger imports from YAML, live "try it" calls, multi-language code generation — recursive React components underneath.
• Shipped across the public docs portals — theming, SEO, SSR/prefetch performance — and the content import/sync pipelines (Confluence, Google, GitHub) with the mdast↔Slate markdown converter.
• Owned headless-PDF export end to end (Puppeteer worker + CSS fidelity, Dockerized on Azure), plus customer-critical fixes from triage to resolution.
• Reduced the initial JavaScript bundle by 50% via tree-shaking and barrel-file elimination, across a codebase serving thousands of documents.
• Built a Manifest V3 Chrome extension solo — live on the Chrome Web Store — turning webpages into structured docs via screenshots and Markdown conversion.

Product consultancy — four client products in parallel, four different stacks.

• Shipped full-stack features across four codebases — React, Vue.js, AngularJS, Node.js, AdonisJS — switching stacks per client without a ramp-up.
• Designed reusable component architectures with clean abstractions and dependency injection.
• Worked deep in complex existing codebases, across multiple teams — the adaptability-and-ownership kind of consulting.
• Built a major bank's contract-PDF template — still printing their contracts today.

Furniture e-commerce across multiple countries — Black Friday-scale traffic.

• Migrated the storefront from legacy Backbone.js to Vue.js with SSR — both systems live in parallel through the switch.
• Built the Cordova mobile app (iOS & Android) from the same codebase as the website.

Enterprise delivery for a well-known US newspaper.

• Full-stack features and backend services in a large enterprise team — JavaScript, Node.js, Go.

Agency work — frontend interfaces and AngularJS applications.

• Built frontend interfaces and AngularJS apps — HTML, CSS/SCSS, JavaScript, jQuery, Node.js, WordPress, Drupal.
• Git Flow, Jira, Gulp — the modern frontend workflow of the era.

First dev role.

• Built the company website and produced HTML/CSS educational content.
• Early SEO, customer acquisition, and client web projects.