Since pyxform 2.1.0 (released Sep 2024) it is possible to exchange bytes with xls2xform.convert, instead of the pattern pyxform-http currently uses of writing out to a file for xls2xform.xls2xform_convert then reading the result file(s) to send back - as seen here. If ODK validate is run (which it currently is by default), pyxform has to write out the XForm XML for that, at least until odk validate can accept data via stdin getodk/validate#97. If both of these items are resolved then pyxform-http would not need filesystem write access.
Since pyxform 2.1.0 (released Sep 2024) it is possible to exchange bytes with
xls2xform.convert, instead of the pattern pyxform-http currently uses of writing out to a file forxls2xform.xls2xform_convertthen reading the result file(s) to send back - as seen here. If ODK validate is run (which it currently is by default), pyxform has to write out the XForm XML for that, at least until odk validate can accept data via stdin getodk/validate#97. If both of these items are resolved then pyxform-http would not need filesystem write access.