Writer finds way into literary festival (5)
I believe the answer is:
hardy
'writer' is the definition.
(Thomas Hardy)
'way into literary festival' is the wordplay.
'way' becomes 'rd' (**).
'into' is an insertion indicator.
'literary festival' becomes 'hay' (annual literary festival in Wales).
'rd' going inside 'hay' is 'HARDY'.
'finds' is the link.
(Other definitions for hardy that I've seen before include "Stalwart" , "standing the test of time?" , "Brave" , "bold" , "Rugged; author" .)