Perfectionist provided ultimately faultless puzzle (8)
I believe the answer is:
stickler
'perfectionist' is the definition.
(as in a stickler for the rules)
'ultimately faultless puzzle' is the wordplay.
'ultimately faultless' becomes 's' (I can't explain this - if you can you should believe this answer much more).
'puzzle' becomes 'tickler' (I've seen this before).
's'+'tickler'='STICKLER'
'provided' acts as a link.
Can you help me to learn more?
(Other definitions for stickler that I've seen before include "Nit-picker" , "Trickles for someone who insists" , "Particular person" , "One who insists on something, like punctuality" , "I may do that precisely" .)