The regulator of a number field is defined in terms of values of the logarithm function evaluated at units of this number field. Similarly, one can define the p-adic regulator of a number field in terms of the p-adic logarithm, and this p-adic logarithm can be interpreted as a function taking values in a syntomic cohomology group. Motivated by questions in 3-manifold topology, Garoufalidis--Scholze--Wheeler--Zagier have recently introduced the notion of Habiro ring of a number field, in order to capture the arithmetic behaviour of certain q-series. In this talk, I want to explain how to define a refinement of the p-adic regulator of a number field in this context, called the cyclosyntomic regulator, in terms of a variant of Bhatt--Lurie's prismatic logarithm. This is based on joint work with Quentin Gazda.