Using node 9.4.0 and doing jspm install throwing below error.
warn Error on getOverride for jspm:npm
TypeError: "timeout" must be an unsigned integer
at validateTimeout (child_process.js:623:11)
at Object.exports.execFile (child_process.js:202:3)
at exports.exec (child_process.js:139:18)
node: 9.4.0 npm: 5.6.0 jspm: 0.16.55
Issue is fixed and was related to the jspm-registry version which needs to be 0.4.4. Posted the issue in jspm github and solution is here