Using tapdance with keymap.json in QMK

Hey all, Wondering if its possible to keep keymap in keymap.json while using the tapdance and some other custom code for hold functions in keymap.c? Having the keymap.json makes it possible to use online configurator which makes changes very easy. I've used qmk c2json but it doesn work with all keys so just wondering if there is a way to keep using keymap.json while having custom code for tapdance etc in keymap.c Thank you