βIO⁻⁹∞LUDIC⁹ is a speculative fermentation lab and sensorial playground that explores the intersections of food, play, and microbial cohabitation. Reimagining fermentation as a living, bubbling, participatory ritual, the project invites visitors CUM BACTER into a soft bacterial kitchen — where things ferment, smell, sound, and grow. By cultivating edible, aromatic, and living materials with symbiotic cultures of bacteria and yeast (AAB, LAB), the lab proposes new ways of sensing, digesting, and designing — co-growing materials rather than extracting them. Fermentation here becomes a joyful act of care, curiosity, and transformation. The lab challenges sanitized, industrial food models and instead embraces slowness, decay, biodiversity, and speculative taste. Rooted in ecological thinking and inspired by traditional and experimental fermentation practices — including those from salt-tolerant ecosystems — βIO⁻⁹∞LUDIC⁹ is also a multispecies social space. It gathers designers, artists, scientists, microbes, children, and dreamers around shared rituals of tasting, listening, and imagining food futures. Through edible prototypes, microbial soundscapes, and playful installations, the project sparks wonder and reflection on what it means to eat, to play, and to coexist.