R Systems Node Js Developer interview questions

About yourself Project details and your KRAs Event Emitters, Middlewares and ExpressJs. Multitasking, async and await, Callbacks. What authorization technique you follow to secure an API. One logical questions "If someone stolen your JWT token how will you secure." JS practical questions. Diff between map, reduce and filter functions let str="Sehdev" //count characters occurence //output {s:1, e:2, h:1, d:1, v:1}