Made a heap, like the piper round the corner (5)
I believe the answer is:
piled
'made a heap' is the definition.
(I've seen this in another clue)
'like the piper round the corner' is the wordplay.
'like the piper' becomes 'pied-' (I've seen this in another clue).
'round' is an insertion indicator.
'the corner' becomes 'l' (I can't explain this - if you can you should believe this answer much more).
'pied' going around 'l' is 'PILED'.
Can you help me to learn more?
(Other definitions for piled that I've seen before include "Heaped" , "put in a heap" , "Arranged in stacks" .)