CV

SUMMARY

Senior full-stack engineer specializing in TypeScript, React, Node.js, and AI, with 30 years of professional experience. Building web applications with LLM integration, using agentic coding tools (Claude Code, Cursor).

EXPERIENCE

Parloa – AI-based contact center platform
Frontend Developer | Mar 2025 – Dec 2025

Parloa is an AI scaleup with a $3 billion valuation, serving Booking.com, American Express, Decathlon, and Allianz
Designed and implemented a server-driven UI (SDUI) package, enabling backend developers to declaratively build UIs for their services.
Built platform features
Developed primarily through agentic AI coding (Claude Code, Cursor)
Tech: TypeScript, React, Next.js, Ant Design, Vite, Storybook, Testing Library, tRPC, OpenAPI

seabo – Freightship Chartering SaaS Platform
Lead Full-Stack Developer | Oct 2022 – Apr 2024

Selected and introduced NestJS as replacement for the legacy PHP backend
Built and extended chartering marketplace
Built vessel database, added subscription billing, redesigned realtime updates
Lead frontend and fullstack developers and drove technology decisions (NestJS, OpenAPI, BullMQ, TypeORM)
Tech: TypeScript, React, Node.js, NestJS, MySQL, OpenAPI, TypeORM, Stripe, Redis, BullMQ, socket.io

ISV (Confidential) – SaaS Development
Lead Frontend Developer | Jul 2020 – Sep 2022

Modernized 7-year-old JavaScript React codebase: migrated to TypeScript, introduced automated testing, adopted component library
Led and coached 3-person frontend team, increasing velocity while improving quality and adding new features to legacy product
Tech: TypeScript, React, Redux, React Query, Jest, React Testing Library, Ant Design

Zalando – Procurement Portal
Lead Frontend Developer, Coach | Sep 2019 – Mar 2020

Led greenfield frontend development for Zalando's procurement platform, supporting €1 billion in annual fashion purchases
Selected technologies, designed frontend architecture, and coached 4 developers with React and MobX workshops in team of 12
Tech: TypeScript, React, MobX, GraphQL, Apollo, Ant Design, Material-UI, Jest, React Testing Library

DMG – Dentamile Connect (Dental CAD/CAM SaaS)
Frontend Developer | Jan 2019 – Aug 2019

Built SaaS for digital production of dental products (crowns, bite splints) with browser-based 3D CAD using WebGL
Designed and negotiated API between SaaS and WebGL CAD component built by partner agency; set up UI component library
Tech: JavaScript, React, Redux, Node.js, REST, Swagger, Jest, Storybook, Webpack

Selected Earlier Projects (full history: stefanwille.com/work)


2018	Intersection	Frontend Developer	React
2017–2018	HRS Innovation Lab	Fullstack Developer	React, Node.js
2016	Movinga	Fullstack Developer	React, Node.js
2016	Jobkraftwerk	Lead Frontend Developer	React
2015	Nokia HERE	Lead Backend Developer	Ruby on Rails
2014	Fyber	Backend Teamlead	Ruby on Rails
2013–2014	SAP	Backend Developer	Ruby on Rails
2009–2013	Papersmart / Balao	CTO & Co-Founder	Ruby on Rails
2002–2009	BizSphere, O2, Reuters	Team Lead / Senior Developer	Java EE
1996–2000	NETLIFE	VP Research & Development	C++, Java

PROJECTS & PUBLICATIONS

Billet – CLI coding agent built directly on the Anthropic SDK: agentic loop, bash and text editor tools, plan mode, eval suite (TypeScript, Anthropic SDK, Bun) – GitHub
Smart Rename – AI-powered desktop app that extracts invoice metadata and auto-renames files (Vercel AI SDK, Evalite, Tauri, TypeScript, React) – stefanwille.com/smart-rename
Recto – published web tool for planning book page layouts, in production use on a 400-page book project (TypeScript, React, Supabase) – rectostudio.com
Author of two books on Java and enterprise software development

EDUCATION & LANGUAGES

Bachelor in Computer Science, University of Hamburg
German – Native (C2) · English – Fluent (C1)