Γεια σου!
There is no clear translation of this term in greek. We use the english term or the word programmer.
So you can say: ''Είμαι web developer/Είμαι προγραμματιστής''. Most of the times companies in their ads say "Ζητείται web developer-προγραμματιστής''.
In our field(I am a computer engineer) we usually use the english terms. :)
ελπίζω να σε βοήθησα!