What it is
Hydra, by Olivia Jack, is live coding for visuals with an analog video-synth soul. Open the browser editor, type osc().rotate(0.1).out(), and a pattern is running. Functions chain like signal paths (oscillators, feedback, keying, modulation), audio reactivity is one call away, and the whole point is editing the code as performance, projected, in front of the audience.
It comes from the algorave and live-coding scene, where the screen showing your code IS the show. As a first contact with generative visuals it is magic: the distance from nothing to something beautiful is one line.
What it costs
Free, open source, runs in any browser.
Best for
Live coders, teachers introducing generative visuals, and producers who want to understand feedback-based visual thinking by playing with it directly.
Skip it if
You need show infrastructure (outputs, decks, mapping) or polish beyond the video-synth aesthetic. Hydra is an instrument and a philosophy; it is deliberately not a rig.