Smelter
Toolkit for real-time, low latency, programmable video, audio mixing
...Smelter provides React components that make programmable composition easier to express in familiar UI code. It can support workflows such as livestreaming, video conferencing, broadcast tools, virtual events, live shopping, and custom media production systems. Its main value is giving developers a flexible composition engine for real-time media instead of forcing them into fixed video layouts or manual production tools.