SG

Hi! I'm Sebastian Gräf, German product engineer with a strong online marketing background as a professional affiliate marketer. I'm making things on the web since 2003.

Contact me

# About me

Product Engineer

I can help companies build web products and internal tools in an AI-driven, transparent and truly full-stack way. From product management, design, and development to SEO. I have experience working solo and in international teams and with B2C and B2B products.

Applied AI

I've been using AI APIs since they became available and working exclusively with coding agents since mid 2025. I've built a domain discovery agent scoring tens of thousands of sources daily, a multiplayer gifting app, and a gut health scanner. Beyond production apps, I've experimented with an AI agent coordination platform and a personal AI assistant.

Interested in working together?

# Testimonials

“I can highly recommend Sebastian. Always delivering on time, great eye for details, state of the art knowledge and use of framework and best practices (especially regarding React and GraphQL) and just practical and pleasant to work with!”

Alexander Barge, CTO @ deineStudienfinanzierung

# Experience

Resume

Oct 2018 - Present, Everywhere - Remote
Freelance Developer
Sebastian Graef LLC
Software development, consulting, and domain investments & development.
NonHormonal.com↗
LumpiniPark.com↗
EUAILaw.com↗
LaunchableDomains↗
Discontinued
GutSpec↗
RateThis
Jun 2024 - Jun 2025
Built full-stack SaaS from scratch to help businesses automate customer reviews and collect feedback (Laravel, Livewire, AlpineJS, Tailwind).
Discontinued
15 months contract at deineStudienfinanzierung
Mar 2019 - Jun 2020
Developed web app (React, Prisma, GraphQL) digitizing student loans & BAföG in Germany, and created marketing website with blog (Gatsby, WordPress).
Jan 2021 - Feb 2024, Bangkok - Remote
Senior Developer
Lifull Connect
Full stack development for Dotproperty / FazWaz, a Lifull Connect company, on some of the largest B2C real estate portals in South East Asia with millions of monthly visitors across different tech stacks:
- Engineered full-stack features and improved portals Dotproperty, ThailandProperty (Laravel, PHP, Vue, JS, MariaDB), Hipflat (RoR, Ruby, JS, MongoDB) and microservices (Kotlin).
- Led frontend modernization in vanilla JS and Tailwind with a streamlined build process resulting in smaller bundles and better developer experience.
- Spearheaded web performance initiative boosting Core Web Vitals for SEO by >100%.
- Migrated main data sources from heavy XML imports to a shared GraphQL API reflecting property listing changes in real-time while preserving legacy architecture.
- Built custom real estate GPT for the GPT Store launch and collaborated with marketing on high-traffic event web apps (Vue, NextJS).
- Drove code quality and test coverage via TDD and pair programming; cut infrastructure & API costs by ~50%; screened engineering candidates.
Dec 2015 - Dec 2017, Zurich - Onsite
Software Engineer
Polynorm Software
- Developed frontend of a complex new B2B product, a PIM system with CMS.
- Migrated first prototype from jQuery to a React app with a modern build process.
- Introduced JavaScript unit tests to improve code quality and maintainability.
Jul 2006 - Oct 2015, Berlin - Remote
Self Employed
Managing Director & Frontend Developer
enter digital ventures, Dec 2014 - Oct 2015
Developed the frontend of two SaaS apps (AngularJS) from idea to launch.
Created two lightweight embeddable widgets (Preact) distributed via CDN.
Planned a content marketing strategy generating thousands of organic social shares.
Owner, Web Developer & Online Marketer
newgo media, Jul 2006 - Oct 2015
Acquired, developed, and monetized premium .de domain assets including Handball.de.
Realized ~50 web projects (PHP, JavaScript) and managed a portfolio of up to 1,500 domains.
Executed performance marketing campaigns via SEM (AdWords) and SEO.