I just noticed a small (8cm) patch of oil on the drive. Had a look under the car and part of the engine is covered in oil.
A closer inspection with my phone reveals that one of the bolts is missing from it!
Any ideas what part this would be, or perhaps is there a common flaw which causes a leak here?
Not a job I'll try to tackle myself, I'll take it to the mechanic next week and monitor oil levels until then. I'm just curious about what it could be.