We review and extend the description of ultradifferentiable functions by their almost analytic extensions, i.e., extensions to the complex domain with specific vanishing rate of the $\overline{\partial}$-derivative near the real domain.
We work in a general uniform framework of ultradifferentiable classes defined by weight matrices and which comprises the main classical ultradifferentiable spaces defined by weight sequences and weight functions but also allows to treat unions and intersections of such.

This is a joint work with Armin Rainer and David N. Nenning (University of Vienna) and Stefan Fürdös (University of Brno).