Fast comparison between two objects

Question

I need a fast way to compare between two objects.

I need the properties whose values changed, and also the properties that were added. Some of the properties have values that are arrays or objects.

Example:

{a: 1, b: "hi",} 

compared with

{b: "hmm", c: 3,}

result:

{b: "hmm", c: 3,}