I like two announce two of my packages: 1. comfort-array http://hackage.haskell.org/package/comfort-array It provides Boxed and Storable arrays with very liberal shape definitions. You may use ranges of indices like in 'array' or zero-based indexing like in 'repa', but you can also use arbitrary index Sets, enumerations, concatenation of arrays and more. E.g. an array with (Shape.Enumeration Ordering) has three elements with indices LT, EQ, GT. 2. lapack http://hackage.haskell.org/package/lapack A high-level interface to the numerical Linear Algebra package LAPACK. It is based on comfort-array, which means that a vector can have a rich structure. E.g. matrix vector multiplication has the signature: (#*|) :: Matrix.General height width a -> Vector width a -> Vector height a Thus, a 'Matrix.General (Shape.Enumeration Ordering) (h,w) a' would map a rectangular array with dimensions h and w to a three-element vector with indices LT, EQ, GT. The LAPACK interface provides solvers for simultaneous linear equations, linear least-squares problems, eigenvalue and singular value problems for square, triangular, symmetric, Hermitian, banded and banded Hermitian matrices, as LAPACK supports them. For a motivating example refer to: http://code.henning-thielemann.de/bob2019/main.pdf