gistfile1.txt

  export function sinceFromTimestamp(timestamp) {
    if (!timestamp) {
      return null;
    }

    // convert from timestamp to delta since now
    // 2013-04-26T145:01:17+0200
    var time = Date.parse(timestamp);
    var now = Date.now();
    var diff = now - time;
    return diff;
  }

Its in fact the values calculated it barfs about

export function sinceFromTimestamp(timestamp: number) {
if (!timestamp) {
return null;
}

// convert from timestamp to delta since now
// 2013-04-26T145:01:17+0200
var time = new Date(timestamp);
var now = new Date();
var diff = now.getTime() - time.getTime();
return diff;

}