A job you are safe and at home in? (8)
I believe the answer is:
sinecure
'a job' is the definition.
(sinecure is a kind of job)
'at home in?' is the wordplay.
'at' becomes 'secure' (I am not sure about this - if you are sure you should believe this answer much more).
'home' becomes 'in' ('he's home' can mean 'he's in').
'in?' means one lot of letters goes inside another.
'secure' going around 'in' is 'SINECURE'.
'you are safe and' is the link.
I am not very happy about this link. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for sinecure that I've seen before include "Job for easy money" , "Paid job with minimal work - insecure (anag)" , "Paid job involving little or no work" , "Soft job, may be insecure" , "An office without work." .)