GUSEK is a compact, open-source Windows IDE for operations research (OR) and decision scientists. It bundles GLPK (GNU Linear Programming Kit) with a customized SciTE (Scintilla Text Editor) editor for modeling and solving LP (Linear Programming) and MILP (Mixed Integer Linear Programming) problems.

It supports GMPL / MathProg (.mod), data files (.dat), GLPK model files (.glp), and common formats like .mps (Mathematical Programming System format) and .lp (CPLEX LP format).

It is portable and GPL-licensed (GNU General Public License), which makes it handy for quick prototyping or teaching optimization.

Created by Luiz Bettoni, development ran from 12 June 2008 to 19 March 2018 (~10 years).