On 8/9/2019 at 5:02 PM, ongamex92 said:
Nuklear is pretty much skinnable.
Dear ImGui has skinning options, but they are quite limited.
While Nuklear has some skinning options, one thing is take into account is whether it goes to point that is satisfactory for the needs of your game.
Dear ImGui is less skinnable but arguably has more ui features, e.g. drag and drop api, tab bars, docking, gamepad controls and some keyboard controls, support for extracting windows as native OS/platform windows, a larger community of users and widgets, etc. and upcoming ones: automation, tables. Whereas Nuklear appears stagnant by now (vurtun moved on to something else?).
My personal answer to the OP is that neither Dear ImGui nor Nuklear are designed for high quality in-game UI and you are better off writing your own. Game UI are very custom and simpler to write than productivity/tooling UI.