Do you perform testing of your code?

Yes, I always try to test my code to ensure its correctness and prevent errors.

In Node.js, testing frameworks like Jest or Mocha are usually used for this purpose.

Here's a simple test example with Jest:

// sum.js
function sum(a, b) {
  return a + b;
}
module.exports = sum;

// sum.test.js
const sum = require('./sum');

test('adds 1 + 2 to equal 3', () => {
  expect(sum(1, 2)).toBe(3);
});

Testing helps identify bugs early and makes code maintenance easier.