This is a Berberis thunbergii aurea I started seven years ago, shown today in the first bonsai pot I made. The pot's a little rough but I like the glaze.
Here's an update, I gave it a trim today. The longest shoots have hardened, while newer shoots are still soft and have been left to grow.
Before and after attached.
I've been only trimming the apex/ main trunk in the fall, so it stays bigger than the rest of the tree.
The tree today. The first hot day of summer came after many cool days, and it hit 100 degrees. Although I watered the tree three times that day, the leaves got crispy so perhaps the pot overheated and damaged the roots. The lesson is that I should have moved it into shade. I was forced to defoliate the tree, and took the opportunity to cut it back hard. It's been on a partial shade bench ever since.
The end result is a more compact tree, although with less ramification.