The compiler's favourite American drive (7)
I believe the answer is:
impetus
'drive' is the definition.
(impetus is a drive to do something)
'the compiler's favourite american' is the wordplay.
'the compiler's' becomes 'im' (I've seen this in other clues).
'favourite' becomes 'pet' (synonyms).
'american' becomes 'US' (abbreviation for United States).
'im'+'pet'+'us'='IMPETUS'
(Other definitions for impetus that I've seen before include "Moving force" , "Momentum, stimulus" , "Driving force, forward movement" , "Incentive - time's up (anag)" , "Incentive, stimulus" .)