A while ago I discussed here some of the issues around targeting ES modules (which nbb does) and the necessity of having people add $default to their namespace names. There seemed to be no way around this since the JS world imposed this breakage and it would be highly disputable if a tool like nbb would have to "compensate" for that. Also when targeting ES modules with shadow (via :target :esm ) you end up with the exact same $default stuff, so at least it's compatible from that perspective (although vanilla CLJS currently doesn't emit ES modules). So with that settled, someone wrote a multi-namespaced project which consumes node libraries, but he (@chris358) tried to make it work with both shadow-cljs (target node-script) and nbb, but then this CJS vs. ESM stuff came up again. I believe I've found a workaround for this situation by • introducing reader conditionals for nbb :

#?(:org.babashka/nbb  ["cookie-parser$default" :as r-cookies] 
    :cljs ["cookie-parser" :as r-cookies])