Eccentric chap, one working in programming, including games principally (6)
I believe the answer is:
codger
'eccentric chap' is the definition.
The definition and answer can be both people as well as being singular nouns.
Perhaps there's a link between them I don't understand?
'one working in programming including games principally' is the wordplay.
'one working in programming' becomes 'coder' (I can't justify this - if you can you should give a lot more credence to this answer).
'including' means one lot of letters goes inside another.
'principally' says to take the initial letters.
The first letter of 'games' is 'g'.
'coder' placed around 'g' is 'CODGER'.
Can you help me to learn more?
(Other definitions for codger that I've seen before include "(Old) man" , "fellow" , "Old bloke" , "A senior" , "Old geezer" .)