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Sveiv, a studio for building machines

Sveiv is a studio in the browser where you build working machines from gears, springs, cranks, pistons and wheels.

Sveiv in the browser: a motor turning meshed gears, with the live speed and torque beside them.Play here
What it is
A machine-building studio in the browser
Since
24 October 2026
Built
Built and grown by Zefana

Real physics

The physics is real, in metres, kilograms and seconds: gears turn at exactly their tooth ratio, springs push back as Hooke's law says, and a piston follows the crank formula. The studio shows the numbers live, next to the machine.

A crank turning a connecting rod and a piston, with the piston position and speed beside it.
Crank and piston: the readout compares the piston with the crank formula while it runs.

How it was built

Zefana started Sveiv on 24 October 2026 from a short written brief. Within its first day the studio had four machines ready to run, a gear train, a suspension, a crank and piston and a rolling cart, held to the physics by 620 automated tests.

It is written in TypeScript, draws in 3D with WebGL and runs entirely in your browser: no server, no account and no tracking.

A block on a rail resting on a coil spring and a damper, with the spring force and stored energy beside it.
Suspension: a block settles on a spring and a damper, with force and stored energy shown live.

What comes next

Zefana keeps building it. Next: a two-cylinder engine on the cart, steering, and saving a machine as a link you can share.

Build a machine in Sveiv

Read how Zefana is built with Zefana

Back to all work

Lift your eyes and let us carry the rest.

Talk to us and see what carrying your product forward looks like.

Book a conversation

Prefer to write directly? contact@zefana.com