🚀 React Interview Experience (August 2025): CapGemini(Part-1)

Overview

This case study presents a React developer interview experience at CapGemini in August 2025. The interview focused on assessing the candidate's understanding of core JavaScript concepts, including variable hoisting, scope, and immediately invoked function expressions (IIFEs), as well as React Router fundamentals.

Interview Rounds

The interview consisted of a series of technical questions designed to evaluate the candidate's knowledge and problem-solving abilities. The questions covered the following topics:

• Question 1: Variable declaration and hoisting with var.

  var a;
  console.log(a);
  a = 20;
  console.log(a);
  var a = 30;
  

  Expected Output:

  undefined
  20
  

• Question 2: Variable declaration and scope with let.

  let a;
  let a = 20;
  console.log(a);
  

  Expected Output:

  SyntaxError: Identifier 'a' has already been declared
  

• Question 3: Variable declaration and initialization with const.

  const a;
  a = 20;
  console.log(a)
  

  Expected Output:

  SyntaxError: Missing initializer in const declaration
  

• Question 4: Variable declaration and initialization with const (again).

  const a;
  console.log(a)
  

  Expected Output:

  SyntaxError: Missing initializer in const declaration
  

• Question 5: Hoisting of functions and function expressions.

  foo();
  var foo = function() {
     console.log("foo");
  }
  bar();
  function bar() {
     console.log("bar");
  }
  

  Expected Output:

  TypeError: foo is not a function
  

• Question 6: Immediately Invoked Function Expressions (IIFEs) and semicolon insertion.

  (function(){
  console.log('abc');
  })()
  ( () => { console.log('abc'); })();