I am trying to run the guestbook-postgres of the Web Development with Clojure, 3rd edition. When I run shadow-cljs I get

$ npx shadow-cljs watch app
shadow-cljs - config: /Users/riccardotacconi/dev/clojure/code/guestbook-postgres/shadow-cljs.edn  cli version: 2.8.52  node: v14.16.0
shadow-cljs - running: lein run -m shadow.cljs.devtools.cli --npm watch app
OpenJDK 64-Bit Server VM warning: Options -Xverify:none and -noverify were deprecated in JDK 13 and will likely be removed in a future release.
[:failed-to-compare "^16.13.0" "16.13.0" #error {
 :cause "Cannot invoke \"Object.getClass()\" because \"target\" is null"
 [{:type java.lang.NullPointerException
   :message "Cannot invoke \"Object.getClass()\" because \"target\" is null"
   :at [clojure.lang.Reflector invokeInstanceMethod "" 97]}]


any idea why?