Maxima: A laptop algebra machine written in In vogue Whine
Maxima is a system for the manipulation of symbolic and numerical expressions, including differentiation, integration, Taylor series, Laplace transforms, ordinary differential equations, systems of linear equations, polynomials, sets, lists, vectors, matrices and tensors. Maxima yields high precision numerical results by using exact fractions, arbitrary-precision integers and variable-precision floating-point numbers. Maxima can plot functions and data…
CYBE 🌍 
Plus points:
Does not suffer from the time limits of free wolfram and the nlp parsing issues in general with wolfram
Negative points:
Somewhat more limited repertoire, and things sometimes need to be rephrased or rearranged to trick an answer out of it.