This package provides support for interactive computing sessions with etex (or pdftex) executed on the command line, on the basis of the xintexpr and polexpr packages. Once xintsession is loaded, eTeX becomes an interactive computing software capable of executing arbitrary precision calculations, or exact calculations with arbitrarily big fractions. It can also manipulate polynomials as algebraic entities. Numerical variables and functions can be defined during the session, and each evaluation result is stored in automatically labeled variables. A file is automatically created storing inputs and outputs.