Small amount of code left (6)
I believe the answer is:
morsel
'small amount' is the definition.
'morsel' can be an answer for 'amount' (morsel is a kind of amount). I'm not sure about the 'small' bit.
'code left' is the wordplay.
'code' becomes 'morse' (Morse code).
'left' becomes 'l' (common abbreviation).
'morse'+'l'='MORSEL'
'of' acts as a link.
Can you help me to learn more?
(Other definitions for morsel that I've seen before include "Bite to eat" , "A shred as of bread" , "(Tasty) bit" , "Dainty" , "Small amount of food, a bite" .)