The most common and most likely answer to this crossword clue is the 9 letter word SPINNERET
I've seen this crossword clue in The Guardian
S
P
I
N
N
E
R
E
T
Buddy explains!

The straight part
We know that "Web developer" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case web developer = spinneret.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does SPINNERET mean?
SPINNERET noun- The organ a spider uses to spin its web.
- A multipored device through which a plastic polymer melt is extruded into fibers.