ClojureScript compiler NullPointerException on OS X when trying to compile simple project - clojure

Question

I tried following the ClojureScript quick start guide http://clojurescript.org/guides/quick-start and hit an NPE trying to manually invoke the clojurescript compiler on OS X.
I have java 1.8.0_92
% javac -version
javac 1.8.0_92
I made a new directory (for the sake of completeness ~/tmp/clojure/cljstest/). All paths are relative to this directory. I think I am using version 1.9.293 of clojurescript.
% cat $(which cljsc)
#!/bin/bash
exec java -jar /usr/local/Cellar/clojurescript/1.9.293/libexec/cljs.jar "$#"
The cljsc jar by itself, however, works fine.
% cljsc
Clojure 1.8.0
user=>
I also downloaded the standalone cljs.jar mentioned in the tutorial and checked the md5sum to make sure that they're the same.
% wget https://github.com/clojure/clojurescript/releases/download/r1.9.293/cljs.jar
% md5 cljs.jar
MD5 (cljs.jar) = 658d7b722cebe46e36604baf9eecfcb5
% md5 /usr/local/Cellar/clojurescript/1.9.293/libexec/cljs.jar
MD5 (/usr/local/Cellar/clojurescript/1.9.293/libexec/cljs.jar) = 658d7b722cebe46e36604baf9eecfcb5
I ran
% mkdir -p src/hello_world
and then
% touch ./src/hello_world/core.cljs
The contents of ./src/hello_world/core.cljs are:
(ns hello-world.core)
(enable-console-print!)
(println "Hello World!")
The contents of ./build.clj are:
(require 'cljs.build.api)
(cljs.build.api/build "src" {:output-to "out/main.js"})
I downloaded clojure through homebrew
% where cljsc
/usr/local/bin/cljsc
This is a shell script that I used to locate the .jar
% cat $(which cljsc)
#!/bin/bash
exec java -jar /usr/local/Cellar/clojurescript/1.9.293/libexec/cljs.jar "$#"
I tried running the compiler with the explicit classpath given in the tutorial
% java -cp /usr/local/Cellar/clojurescript/1.9.293/libexec/cljs.jar:src clojure.main build.clj
That produced the following stack trace:
% java -cp /usr/local/Cellar/clojurescript/1.9.293/libexec/cljs.jar:src clojure.main build.clj
Exception in thread "main" java.lang.NullPointerException, compiling:(/Users/gregnisbet/tmp/clojure/cljstest/build.clj:3:1)
at clojure.lang.Compiler.load(Compiler.java:7391)
at clojure.lang.Compiler.loadFile(Compiler.java:7317)
at clojure.main$load_script.invokeStatic(main.clj:275)
at clojure.main$script_opt.invokeStatic(main.clj:335)
at clojure.main$script_opt.invoke(main.clj:330)
at clojure.main$main.invokeStatic(main.clj:421)
at clojure.main$main.doInvoke(main.clj:384)
at clojure.lang.RestFn.invoke(RestFn.java:408)
at clojure.lang.Var.invoke(Var.java:379)
at clojure.lang.AFn.applyToHelper(AFn.java:154)
at clojure.lang.Var.applyTo(Var.java:700)
at clojure.main.main(main.java:37)
Caused by: java.lang.NullPointerException
at cljs.closure$build.invokeStatic(closure.clj:1920)
at cljs.build.api$build.invokeStatic(api.clj:198)
at cljs.build.api$build.invoke(api.clj:187)
at cljs.build.api$build.invokeStatic(api.clj:190)
at cljs.build.api$build.invoke(api.clj:187)
at user$eval24.invokeStatic(build.clj:3)
at user$eval24.invoke(build.clj:3)
at clojure.lang.Compiler.eval(Compiler.java:6927)
at clojure.lang.Compiler.load(Compiler.java:7379)
... 11 more
I expected the clojurescript compiler to either produce main.js or give me a clojurescript-related error message. Why is the ClojureScript compiler throwing a NullPointerException? Is it a compiler bug?