Another option (not in-process) to call clojure from python is through nrepl protocol: https://github.com/cemerick/nrepl-python-client . I use it to use a runninc clojure process from python-based jupyter notebooks. This could be made powerful with transit-python mentioned above (and maybe something like Apache Arrow for sharing huge data structures). For the other side -- calling python from clojure -- this could be useful (but is broken with hylang's current version): https://github.com/Foxboron/HyREPL .