Halfdan Harring has spent years shipping his own products. He works hands-on across the full stack — React, Vite, TypeScript, TailwindCSS, Node.js, Firebase/Firestore — and cares just as much about architecture and test coverage as he does about micro-animation and game-feel.
This page is a short portrait of Halfdan Harring: what he builds, how he works, and where to read his own story or book him for a talk.
What Halfdan Harring builds
Halfdan Harring builds fullstack products with a strong bias towards shipping. His typical stack is React + Vite on the frontend, Node.js/TypeScript on the backend, and Firebase (Auth, Firestore, Cloud Functions, Hosting) as the platform. On top of that, he obsesses over small details — haptics, transitions, empty states, loading states — because he believes that is what makes software feel alive.
Beyond Quiz Fight, Halfdan is the maker behind TaskMondo (task management for SMBs), HeadToHead (realtime football game), a landing-page builder, CRM lead systems, a booking system and a shift-scheduler — all shipped from his own one-person studio. That track record, and the lessons it produced, is what he brings to Quiz Fight every week.
Halfdan Harring the entrepreneur
Halfdan Harring is candid about what it actually takes to build and ship software products as a one-person studio — the focus, the craft, and the discipline of releasing steadily and improving with every version. That practical, no-hype perspective is part of why people ask him to share his story on stage.
If you want the long version, it lives on his personal site. If you want the developer version, it lives on his portfolio. Both are linked below.
Working with Halfdan Harring
You can follow Halfdan Harring’s developer work, read his personal story, or book him as a keynote speaker through the three links below.
- Personal storyhalfdanharring.dkThe personal story of Halfdan Harring — background, journey and the path into building software products.
- Developer portfoliojegudvikler.dkHalfdan Harring’s developer portfolio — fullstack work across React, Vite, Node.js and Firebase.
- Book him as speakerforedragmedhalfdan.dkBook Halfdan Harring for a keynote about entrepreneurship, building software products, and the craft of shipping as a solo developer.
Quiz Fight on the App Store
Quiz Fight is developed and published by Halfdan Harring. You can download the app and see his Apple developer profile directly on the App Store.
Other projects by Halfdan Harring
- Apps with Halfdanappsmedhalfdan.dkAn overview of the apps and digital products Halfdan Harring builds.
- Bloghalfdanharringblog.dkHalfdan Harring’s blog about development, products and entrepreneurship.
- HeadToHeadheadtohead.dkA realtime football game built by Halfdan Harring.
- TaskMondotaskmondo.comTask management for small and medium-sized businesses.
- Runishrunish.appAn app project from Halfdan Harring’s one-person studio.
- Dealer-IDdealer-id.comA SaaS tool developed by Halfdan Harring.
- LostLeadlostlead.onlineA lead tool from Halfdan Harring’s product portfolio.
Official profiles
- GitHubgithub.com/halfdanharringCode and open-source projects from Halfdan Harring.
- Gravatargravatar.com/halfdan1311The public Gravatar profile of Halfdan Harring.
- About.meabout.me/halfdanharringA short introduction to Halfdan Harring and his projects.
- DEV.todev.to/halfdan_harringTechnical posts and articles by Halfdan Harring.
- Aminoamino.dkHalfdan Harring on the Danish entrepreneur community Amino.
- Mediummedium.com/@halfdanharringLonger articles and reflections from Halfdan Harring.
Frequently asked questions about Halfdan Harring
Who is Halfdan Harring?
Halfdan Harring is a Danish fullstack developer and co-founder of Quiz Fight. He has shipped his own products for years — TaskMondo, HeadToHead and a long list of MVPs — and works with React, Vite, Node.js and Firebase.
What is Halfdan Harring’s tech stack?
Halfdan Harring works primarily with TypeScript, React, Vite, TailwindCSS, Node.js and Firebase (Auth, Firestore, Cloud Functions, Hosting). He also uses Capacitor for native iOS/Android wrappers.
Can I book Halfdan Harring as a speaker?
Yes. Halfdan Harring takes speaking engagements about entrepreneurship, product development, and what it takes to build and ship software as a solo developer. Bookings run through foredragmedhalfdan.dk.
Where can I read Halfdan Harring’s story?
His personal story lives on halfdanharring.dk. His developer portfolio — cases, stack and services — lives on jegudvikler.dk.
What products has Halfdan Harring built?
Halfdan Harring has built Quiz Fight, TaskMondo, HeadToHead, a landing-page builder, CRM lead systems, a booking system and a shift-scheduler, among others.
Try the app Halfdan Harring built
Quiz Fight is the product Halfdan Harring spends most of his time on right now. The fastest way to see what he builds is to go play it.