ethereumjs-vm stacktrace

gistfile1.txt

> [email protected] test /home/jwasinger/projects/ethereumjs-vm
> node --harmony ./tests/tester -a

/home/jwasinger/projects/ethereumjs-vm/node_modules/ethereumjs-testing/index.js:22
    }, async (err, content, fileName, next) => {
             ^
SyntaxError: Unexpected token (
    at createScript (vm.js:56:10)
    at Object.runInThisContext (vm.js:97:10)
    at Module._compile (module.js:542:28)
    at Object.Module._extensions..js (module.js:579:10)
    at Module.load (module.js:487:32)
    at tryModuleLoad (module.js:446:12)
    at Function.Module._load (module.js:438:3)
    at require (internal/module.js:20:19)
    at Object.<anonymous> (/home/jwasinger/projects/ethereumjs-vm/tests/tester.js:4:17)
    at Module._compile (module.js:570:32)