This shelf took no time to assemble-30 minutes max. There are no words on the instructions so once you get your self settled, you are good to go. It looks very nice. 

My wall has molding at the bottom so the shelf is not flush against the corner, so it does wobble a little . Something to consider. 

Also, it says is can hold 40lbs ( I think) per shelf. Whatever it was, I would be hesitant to add more than 10 pounds per shelf. It’s more for looks than actual functionality for books….