Full disclosure, I currently work at Mux on the video product. Previously though, I worked at an education startup with user generated video content. Like many others commenting on this thread, I built a simple queuing system using RabbitMQ and celery, transcoding on EC2 with ffmpeg. While we might have saved some money by doing this in house, we almost certainly discouraged users from uploading content because the entire video needed to transcoded before it could be viewed. For use cases like the breaking news or high traffic user generated content, you really want to minimize wait time, and that requires some kind of special sauce. At Mux, we encode content just in time for very fast publish times. It’s very challenging to do this on your own.