Is this on React? What technologies and libraries did you use for forms? Was there validation?

Yes, it's about React. I often use libraries like Formik or React Hook Form for working with forms — they simplify form state management and validation.

Validation can be both synchronous and asynchronous. For example, with React Hook Form, you can integrate Yup for schema validation:

import { useForm } from 'react-hook-form';
import * as yup from 'yup';
import { yupResolver } from '@hookform/resolvers/yup';

const schema = yup.object().shape({
  email: yup.string().email('Invalid email format').required('Required'),
  password: yup.string().min(6, 'Minimum 6 characters').required('Required'),
});

function MyForm() {
  const { register, handleSubmit, formState: { errors } } = useForm({
    resolver: yupResolver(schema)
  });

  const onSubmit = data => console.log(data);

  return (
    <form onSubmit={handleSubmit(onSubmit)}>
      <input {...register('email')} />
      {errors.email && <p>{errors.email.message}</p>}
      <input type="password" {...register('password')} />
      {errors.password && <p>{errors.password.message}</p>}
      <button type="submit">Submit</button>
    </form>
  );
}

Thus, validation is built-in and user-friendly.