Nowadays, several Calphad softwares are available - in a framework of computational thermodynamics - to simulate solidification in systems with more than two components; these have recently been defined as  Calphad Tools for the Metallurgy of Solidification.  In recent years, Calphad-based methodologies have reached maturity in several important fields of metallurgy, and especially in solidification-related processes such as semi-solid casting, 3d printing, and welding, to name a few. While there are important studies devoted to the progress of Calphad methodology, there is still space for a systematization of the field, which proceeds from the ability of most Calphad-based software to simulate solidification curves and includes both fundamental and applied studies on solidification, to be substantially appreciated by a wider community than today. The three applied fields mentioned above could be widened by specific successful examples of simple modeling related to the topic of this issue, with the aim of widening the application of simple and effective tools related to Calphad and Metallurgy. See also "Calphad Tools for the Metallurgy of Solidification" in an ongoing issue of an Open Journal. https://www.mdpi.com/journal/metals/special_issues/Calphad_Solidification
Given a specific chemical composition, using a software for computational thermodynamics - which might be open or commercial - the calculation of the Scheil curve is possible if a thermodynamic database is available.  A good point in favour of some specific commercial softwares is that the  install is easy indeed and you can use it on a windows based system - for instance with  students or for  self training.
One should get some open, chiefly binary, databases (extension *.tdb), one could  find - after registering - at Computational Phase Diagram Database (CPDDB) of the National Institute for Materials Science of Japan,  NIMS https://cpddb.nims.go.jp/index_en.html. They are available - for free - and the collection is rather complete; in fact currently 507 binary systems are available in the thermodynamic data base (tdb) format.   
Some wider and more  specific alloy systems partly open - with tdb compatible format - are available with minor corrections  for Pandat use at Matcalc https://www.matcalc.at/index.php/databases/open-databases.