Random things off the top of my head that are a pain without a framework:<p>- take object of arbitrary depth {a: 1, b: [1, 2, {c: 3}]} and send as querystring parameters to Rails&#x2F;Node&#x2F;PHP&#x2F;whatever backend<p>- take two parallel ajax calls and run some code when they&#x27;re both done<p>- SPA w&#x2F; parameterized urls