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Bjørn Stabell

Entrepreneur / Technologist
Building AI products and open-source developer tools.

About

Co-founded App Annie / data.ai (app market intelligence), Happylatte (mobile games), and Exoweb (agile dev services, 90 people). Running companies since 2000 across Beijing, Vancouver, and now Palo Alto. Also co-created XPilot, one of the first multiplayer internet action games (1991).

Currently building AI products and open-source infrastructure for the terminal ecosystem: Silvery (React TUI framework), terminfo.dev (terminal compatibility database), Termless (headless terminal testing), Flexily (flexbox layout engine), and Tribe (multi-agent coordination for Claude Code).

Projects

Projects and Companies

Companies

Incubating

Working on AI-powered personal productivity tools — intelligent assistants, knowledge management, and local-first sync.

App Annie
data.ai

Co-founder & Board Director, 2010–2024. The industry standard for app market intelligence — used across the Fortune 500 and 1,100+ enterprises worldwide. Incubated inside Exoweb, raised 6 rounds from Sequoia, IDG, IVP, and Greycroft. Grew to 400+ employees. Exit to Sensor Tower in 2024.

Co-founder & CEO, 2009–2016. On a mission to create “newfangled mobile games” that fully leveraged the new smartphone platforms. Incubated inside Exoweb. App Annie was originally built as Happylatte’s internal marketing tool. Raised Series A from Index Ventures.

High Noon

Designer & Product Owner. One-handed gunslinging — your phone is your weapon. Spaghetti western meets Mafia Wars. Top 10 grossing game of the year in 60+ countries, 10M+ downloads.

Pee Monkey

Product Owner. Flappy Bird-style marketing experiment that hit #1 downloaded game in the US, May 2011.

Co-founder & Managing Director, 2000–2009. Agile software services in Beijing, grew to 90 people. Incubated both Happylatte and App Annie.

Open Source — Terminal Ecosystem

React framework for terminal UIs — 30+ components, per-node dirty tracking (100x+ faster than Ink), themes, mouse support.

TypeScript React TUI

The “caniuse.com for terminal emulators” — automated compatibility testing for 161 features across 19 terminals. Powered by Termless.

VitePress Compatibility Database

Headless terminal testing — like Playwright, but for terminal apps. Write tests once, run against 10 terminal emulator backends with 21+ matchers.

TypeScript Testing Terminal

Pure JavaScript flexbox layout engine — Yoga-compatible API, 1.5-5.5x faster, zero WASM. Pretext integration (alpha) for rich text layout.

TypeScript Layout Flexbox

AI Tooling

Multi-agent coordination — cross-session messaging, work tracking, live TUI dashboard, and parallel task orchestration.

Claude Code plugin Multi-agent

Session history search — FTS5-indexed search across past sessions with LLM synthesis and file recovery.

Claude Code plugin Search

Multi-LLM research — second opinions, deep research with web search, and multi-model consensus from GPT, Gemini, Grok, and Perplexity.

Claude Code plugin Research

Headless terminal testing — spawn PTY sessions, send keystrokes, capture screenshots and text via MCP.

Claude Code plugin Testing

GitHub notifications — push events, PR activity, workflow failures, and issue changes delivered as channel messages.

Claude Code plugin GitHub

Batch rename, refactor, and migrate across files — TypeScript symbols, text updates, terminology migrations, and LLM-powered API migrations.

Claude Code plugin Refactoring

Open Source — Developer Tools

One library instead of three — debug, structured logging, and tracing unified. ~3KB, zero dependencies. Used by Silvery, Termless, and terminfo.dev.

TypeScript Logging

Executable markdown testing — your docs are your tests. Persistent context, pattern matching, snapshots.

TypeScript Testing

Fuzz testing and chaos streams for Vitest — monkey-patching, random input generation, differential oracles.

TypeScript Testing

Open Source — Historical

One of the first multiplayer internet action games — dogfighting in space since before the web existed.

Co-author C 1991