If you are looking for one best microtoping company in the UK, Ideal Work Microtoping is amongst the top-notch. The company not only offers the microtoping services to individual, but contractors and people, who want training in this business can also contact them from across the UK.
The bench is supported by custom steel brackets that are anchored to the concrete retaining wall. I've attached a detail for your reference. The design intent was to emphasize a floating plane of wood, rather than bringing attention to the connection.