shadow-cljs: shadow-cljs server shuts down with `RejectedExecutionException` when running `npx shadow-cljs watch app` (macOS)

possible-solutions.markdown

1. In your project.clj, try setting your maximum JVM heap size:

   :jvm-opts ["-Xmx2G"]

stacktrace.txt

shadow-cljs - config: /path/to/app/shadow-cljs.edn  cli version: 2.8.52  node: v11.15.0
shadow-cljs - running: lein with-profile +cljs run -m shadow.cljs.devtools.cli --npm watch app
Warning: implicit hook found: lein-environ.plugin/hooks
Hooks are deprecated and will be removed in a future version.
NPM dependency "highlight.js" has installed version "^9.15.10"
"9.15.8" was required by jar:file:/home/foobar/.m2/repository/day8/re-frame/re-frame-10x/0.4.2/re-frame-10x-0.4.2.jar!/deps.cljs
shadow-cljs - server version: 2.8.52 running at http://localhost:9630
shadow-cljs - nREPL server started on port 50001
shadow-cljs - watching build :app
[:app] Configuring build.
[:app] Compiling ...
shutting down ...
shutting down ...
[:app] Build failure:
RejectedExecutionException: Task java.util.concurrent.FutureTask@7249f31f rejected from java.util.concurrent.ThreadPoolExecutor@273195bb[Terminated, pool size = 0, active threads = 0, queued tasks = 0, completed tasks = 306]
  java.util.concurrent.ThreadPoolExecutor$AbortPolicy.rejectedExecution (ThreadPoolExecutor.java:2063)
  java.util.concurrent.ThreadPoolExecutor.reject (ThreadPoolExecutor.java:830)
  java.util.concurrent.ThreadPoolExecutor.execute (ThreadPoolExecutor.java:1379)
  java.util.concurrent.AbstractExecutorService.submit (AbstractExecutorService.java:112)
  sun.reflect.NativeMethodAccessorImpl.invoke0 (NativeMethodAccessorImpl.java:-2)
  sun.reflect.NativeMethodAccessorImpl.invoke (NativeMethodAccessorImpl.java:62)
  sun.reflect.DelegatingMethodAccessorImpl.invoke (DelegatingMethodAccessorImpl.java:43)
  java.lang.reflect.Method.invoke (Method.java:498)
  clojure.lang.Reflector.invokeMatchingMethod (Reflector.java:167)
  clojure.lang.Reflector.invokeInstanceMethod (Reflector.java:102)
  shadow.build.async/queue-task (async.clj:11)
  shadow.build.async/queue-task (async.clj:4)
  shadow.build.output/flush-sources (output.clj:245)
  shadow.build.output/flush-sources (output.clj:240)
  shadow.build.output/flush-sources (output.clj:242)
  shadow.build.output/flush-sources (output.clj:240)
  shadow.build.targets.browser/flush-unoptimized! (browser.clj:654)
  shadow.build.targets.browser/flush-unoptimized! (browser.clj:642)
  shadow.build.targets.browser/flush-unoptimized (browser.clj:668)
  shadow.build.targets.browser/flush-unoptimized (browser.clj:665)
  shadow.build.targets.browser/flush (browser.clj:679)
  shadow.build.targets.browser/flush (browser.clj:671)
  shadow.build.targets.browser/process (browser.clj:823)
  shadow.build.targets.browser/process (browser.clj:801)
  clojure.lang.Var.invoke (Var.java:384)
  shadow.build/process-stage/fn--14088 (build.clj:143)
  shadow.build/process-stage (build.clj:140)
  shadow.build/process-stage (build.clj:132)
  shadow.build/flush (build.clj:423)
  shadow.build/flush (build.clj:418)
  shadow.cljs.devtools.server.worker.impl/build-compile (impl.clj:315)
  shadow.cljs.devtools.server.worker.impl/build-compile (impl.clj:300)
  shadow.cljs.devtools.server.worker.impl/eval15252/fn--15254 (impl.clj:695)
  clojure.lang.MultiFn.invoke (MultiFn.java:234)
  shadow.cljs.devtools.server.util/server-thread/fn--14897/fn--14898/fn--14906 (util.clj:285)
  shadow.cljs.devtools.server.util/server-thread/fn--14897/fn--14898 (util.clj:284)
  shadow.cljs.devtools.server.util/server-thread/fn--14897 (util.clj:257)
  java.lang.Thread.run (Thread.java:748)

Worker shutdown.