building tez-ui throws exceptions

Could not find watchman, falling back to NodeWatcher for file system events.
Visit http://www.ember-cli.com/user-guide/#watchman for more info.
Building/home/rajesh/tez/apache-tez-0.8.5-src/tez-ui2/src/main/webapp/node_modules/ember-cli-htmlbars/node_modules/broccoli-persistent-filter/node_modules/async-disk-cache/node_modules/username/index.js:2
const os = require('os');
^^^^^
Use of const in strict mode.
/home/rajesh/tez/apache-tez-0.8.5-src/tez-ui2/src/main/webapp/node_modules/ember-cli-htmlbars/node_modules/broccoli-persistent-filter/node_modules/async-disk-cache/node_modules/username/index.js:2
const os = require('os');

▽
^^^^^
SyntaxError: Use of const in strict mode.
    at exports.runInThisContext (vm.js:73:16)
    at Module._compile (module.js:443:25)
    at Object.Module._extensions..js (module.js:478:10)
    at Module.load (module.js:355:32)
    at Function.Module._load (module.js:310:12)
    at Module.require (module.js:365:17)
    at require (module.js:384:17)
    at Object.<anonymous> (/home/rajesh/tez/apache-tez-0.8.5-src/tez-ui2/src/main/webapp/node_modules/ember-cli-htmlbars/node_modules/broccoli-persistent-filter/node_modules/async-disk-cache/index.js:24:16)
    at Module._compile (module.js:460:26)
    at Object.Module._extensions..js (module.js:478:10)

npm ERR! Linux 3.10.0-327.el7.x86_64
npm ERR! argv "/home/rajesh/tez/apache-tez-0.8.5-src/tez-ui2/src/main/webapp/node/node" "/home/rajesh/tez/apache-tez-0.8.5-src/tez-ui2/src/main/webapp/node/npm/bin/npm-cli" "run" "build:mvn"
npm ERR! node v0.12.2
npm ERR! npm  v2.15.3
npm ERR! code ELIFECYCLE
npm ERR! tez-ui@0.2.0 build:mvn: `TMPDIR=tmp node/node ./node_modules/ember-cli/bin/ember build -prod`
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the tez-ui@0.2.0 build:mvn script 'TMPDIR=tmp node/node ./node_modules/ember-cli/bin/ember build -prod'.
npm ERR! This is most likely a problem with the tez-ui package,
npm ERR! not with npm itself.
npm ERR! Tell the author that this fails on your system:
npm ERR!     TMPDIR=tmp node/node ./node_modules/ember-cli/bin/ember build -prod
npm ERR! You can get information on how to open an issue for this project with:
npm ERR!     npm bugs tez-ui
npm ERR! Or if that isn't available, you can get their info via:
npm ERR!
npm ERR!     npm owner ls tez-ui
npm ERR! There is likely additional logging output above.