Merlin Druzinec

macOS app extension platform. Hooks into keyboard and mouse input at the OS level, reads any app's UI through the Accessibility API. Package manager with cryptographic signing for third-party distribution. Rust core with FFI bridge to Bun. Each extension runs in an isolated worker. Electrobun for packaging. Proof of concept built with Tauri.

JavaScript SDK and Auth.js provider for Hanko Passkeys. Added passkey auth to Cal.com (30k+ stars). Auth.js v4 provider, shipped v5 migration + MFA. Documentation and DevRel.

Changelogs, embeddable widget, Stripe billing, bidirectional Slack integration. Blitz.js, Prisma, React, TypeScript.

Milk Video

W21Engineer2022–2023

Graph-based pipeline editor for automating social media content with GPT and Claude. Acquired by Oktopost (June 2025). Maintained a separate legacy codebase in parallel.

Internal tooling for a UK cloud services company. Auth0 multi-tenant system. Next.js, React, TypeScript. CI/CD pipeline.

OPC UA proof-of-concept for industrial machine security. Undocumented library. Had to learn protocol by reading source code. node-opcua, Grafana, nmap. Also built tooling for a Bosch Rexroth event.

Landing page rebuild. 10,000+ words, dozens of graphics recreated in HTML/CSS. Blog, pricing page, competitor comparisons. Next.js, Tailwind CSS. Ghost.org backend, custom frontend rendering.

5–20K DAU. Real-time multiplayer games. Thousands of players betting simultaneously, results resolving live, shared chat. Drove a full frontend rewrite from jQuery to Vue. Wrote a provably fair system — lets players cryptographically verify outcomes were determined before bets. Worked across the entire product: frontend, backend, design, community management, marketing. Separate contracts for ETH payment infrastructure, backend maintenance, and API documentation. Provably fair: commit-reveal with SHA-256. Reverse-engineered undocumented APIs. Redis pub/sub. ETH payments: key management, transaction signing.