Bikepacking - a viable alternative to racks & panniers

https://www.decathlon.co.uk/100-bike-frame-bag-black-15l-id_8354453.html (I sharpied the logo, I am that shallow) with a velcro trouser strap round it, you can also see one on the back of the carradice. It helps keep it nicely compressed, and satisfies my desire for some spare straps and reflectiveness on what looks to be shaping to be a fairly grey week. Only tools and tubes in there so hopefully will go the week without being opened...