Video: Niels Leenheer – The Web Beyond the Edges of the Browser Window

Niels Leenheer has been sitting in the audience at beyond tellerrand for more than ten years. And as I wrote in his speaker introduction, having him step onto the stage that has inspired him all those years felt like exactly the kind of moment this 15th edition deserved.

He opened by saying he never considered himself an artist. That he just builds things out of curiosity, for himself. And that it sometimes produces slightly unhinged results. What followed was forty minutes of exactly that.

”The Web Beyond the Edges of the Browser Window” is about obsessions. Not the tortured kind, but the good kind: that period of clarity and focus where something grabs you and you just have to follow it wherever it goes. Niels has followed his obsessions into some very strange places. Clocks. Laser projectors. Oscilloscopes. Stage lighting rigs. CSS-controlled flamethrowers. And in every single case, the tool he reached for was the web.

The talk moves through several projects, each one born from something Niels saw or heard at a previous beyond tellerrand. A talk by Vasilis van Gemert about gradient clocks sent him head-first into a Raspberry Pi rabbit hole and the creation of badclock, which is a round touchscreen clock powered by a physics simulation so over-engineered it has gravity, breakable hands, a beam mode with 120 simulated ball bearings and a winding knob that will snap the gears if you wind it too much. It is completely impractical and completely wonderful.

Then there is the oscilloscope chapter, which is really several stories in one. The plan was simple: use the Web Audio API to steer the electron beam of a 1980s scope and draw a clock on it. What actually happened involved Niels building a signal generator, finally getting the scope working, playing with it for about an hour, and then — sparks, smoke, a mad scramble for the power plug, and a dead oscilloscope. Undeterred and on a five-hour train to a conference, he built his own oscilloscope simulator from scratch instead, doing a deep dive into electromagnetic force, phosphor physics, and Euler integrations before sensibly deciding he had a life and stopping just short of calculating how electrons excite phosphors. The simulator looked right. That was enough. Once the real scope was repaired, everything he had built just worked. Including Doom, a playable version of the original Asteroids, and Chrome’s offline dinosaur game, all running on vintage hardware via web technology.

The final act is about taking the web off the screen entirely. Niels wanted to control stage lights with CSS. Not as a metaphor – literally: write CSS animations, have the lights respond. He built a DMX controller in the browser using WebUSB, hooked it up to professional stage lights and a smoke machine, and then, almost as an aside, showed a flamethrower he had bought on AliExpress on a train to a previous beyond tellerrand and had some explaining to do about when it arrived at home. The talk ends with CSS animations running on a laser projector – SVGs drawn in light, bouncing around a darkened stage – and Niels quietly noting that he cannot put into words how much fun this is. You can tell.

What I love about this talk is that it never once tries to be more than it is. Niels is not solving problems. He is not building products. He is tinkering, in the very best sense of the word. Following curiosity wherever it leads, using the tools he loves best, and ending up somewhere genuinely surprising every time. He closed by thanking beyond tellerrand for 15 years of inspiration. The feeling, very much, is mutual.

More information about Niels Leenheer on his beyond tellerrand speaker profile page.

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