Some extensions may require additional Makefile or config.m4 code that can't be created by PECL_Gen. Makefile code can be added using a %<makefile%> tag within %<deps>% section. The tag data is written to a Makefile.fragment file and registered within config.m4. Additions to config.m4 itself can be put into a %<configm4>% tag within %<deps>%. You can control whether the code is put near the beginning or the end of config.m4 using the %position=top% or %position=bottom% attribute.