Two YouTube players and a crossfader between them. Paste a playlist, and every track lands in the crate below — every playlist on Refunc's own YouTube stands ready at one tap, the newest four as buttons and the rest behind all playlists, and a pasted one can be named and saved as a button of its own. Tap A or B to throw a record on a deck by hand, or press AUTO MIX and the page plays the whole crate as one continuous set: a few seconds before a track runs out, the next one starts on the other deck and the fader walks across on its own. The proper DJ programs are not allowed to touch YouTube at all — so this one is built from the only thing YouTube does hand out, its own player, twice.

What the fader can and cannot do. YouTube keeps its sound sealed inside the player, so the fader moves the two players' volumes — a real blend, but no tempo-matching and no EQ, because the audio itself is never handed over. Ads belong to YouTube too and will play where YouTube puts them. A track whose owner forbids embedding is struck through in the crate and skipped — and an age-restricted video counts as one: YouTube only plays those on its own site, so AUTO MIX strikes it and moves on after twelve seconds.

On an iPhone the fade is a cut. iOS keeps the volume knob to itself, so there the fader switches at the middle instead of blending — and a deck may ask for one tap on its own play button before it is allowed to sound. The mixer proper lives on the laptop.

Visuals: any site, any search, becomes the light show. Press visuals and the screen goes full-bleed with pictures cut collage-wise on a beat — refunc.nl stands ready as the first source, any address you paste (a pan factory, a toy shop, a greengrocer) becomes a button of its own, saved in this browser, and the same field also searches: type words and press images for a real picture search, or youtube for video thumbnails. A colour swatch is a filter, not a gamble — arm one and the pictures already loaded are sieved down to the ones that really carry that colour, measured on the server because a browser may not read a borrowed picture's pixels. roulette searches fresh pictures for every new track, off the track's own title. Thirty-some compositions never repeat back to back, and settings opens the pro strip: beat division, a blend mode, and autopilot, which fires the trade effects on its own. The rhythm is typed, tapped — or heard: auto asks for the microphone and finds the beat in the room, because YouTube never hands over the audio itself; it wants the music out loud, so headphones keep it deaf, and on a phone iOS may ask every time. Seven effects stand as switches — strobe, pulse, mirror and glitch from the VJ trade, and three of the house: ink (paper-and-ink), print (a printed sheet, hairlines and all) and mark (the wordmark slammed over the picture every beat). The server reads only the one public page you name and returns picture addresses; the pictures come from that site straight to your browser, and a site that refuses hotlinking sifts itself out.

What leaves the page: nothing of yours. The videos come straight from YouTube's player, each title is looked up once at noembed.com, one call to our own scrape.php fetches a source page's picture list, and the crate is remembered in this browser only. No account, no key, nothing stored on any server of ours.