Daniel Schmidt

Frontend engineer working on the difficult parts between product, design and engineering.

I care about architecture, accessibility, performance and developer experience, and about building things that are still pleasant to work with years later.

The day job

At Charlie Tango, I help set the technical direction on larger web projects while staying hands-on as a developer.

I’ve helped shape our frontend platform and engineering practices, led frontend architecture, improved accessibility and testing, mentored developers, and built tooling that makes the work easier for the teams using it.

Built for Umbraco

Open source, for the CMS behind most of that work.

blur-placeholder
Image placeholders generated once, in Umbraco.
Generated when the image is saved and handed to the frontend as one string. Public requests do no work.
Look insideDocs Source
web-analytics
Vercel and Plausible reports inside the Umbraco backoffice.
Traffic, and the numbers for the page being edited, without opening another tab. It reads the analytics you already run.
Look insideDocs Source
@charlietango/umbraco-rich-text
Umbraco rich text, rendered as React components.
Renders the Delivery API rich text JSON as React, with a hook to swap any node or block for a component of your own.
Look insideSource

Open source

I maintain react-intersection-observer, a React library downloaded around 20 million times a month, along with a handful of other projects.

Open source is where I get to scratch the kinds of technical itches that turn up repeatedly in real projects, and occasionally discover that several million other people had the same itch.

react-intersection-observer
Tell a React component when it enters the viewport.
A hook, a render prop, and a component over the Intersection Observer API. It reuses observers where the options match, and ships a test mock so tests do not need a browser.
Look insideDocs Source20M downloads a month

It’s a Unix system!

When I saw Jurassic Park back in 1996, the dinosaurs were cool. But not as cool as the “unix” file system, flown through in 3D to lock the doors. I have wanted to build one ever since.

FSN
Visualize and navigate your file system in 3D space.
Point it at a folder and the files stand up in front of you, in the same arrangement every time you open it.
Source

One got out

It has been hanging over the canyon since 1978, and there are fifty-four more behind it.

Say hello

Sundhedsstyrelsen

A new public health platform built as a shared multisite setup, with accessibility and maintainability treated as part of the architecture.

Solution architect & frontend lead · 2025–2026

sst.dk

Sundhedsstyrelsen's website brings together guidance, recommendations, publications and other public health information for citizens and professionals.

I worked as solution architect and frontend lead on the new platform. The site was built as a headless multisite solution, with a shared frontend foundation that could support the main site and related sites without turning each one into a separate implementation.

A large part of my work was defining that frontend structure and the integration with Umbraco. Shared components, content patterns and technical conventions had to work across sites while still leaving room for different editorial needs.

Accessibility was also part of the implementation from the start rather than something checked at the end. That meant treating component behaviour, content structure and frontend quality as architectural concerns, not just visual ones.

The result is a common foundation that makes it easier to maintain and evolve several sites without rebuilding the same solutions each time.

Client: Sundhedsstyrelsen
Technology: Next.js, React, Vercel, Umbraco Content Delivery API
Work: Frontend architecture, multisite structure, CMS integration, accessibility and technical quality