Sage Math (PIMS Supported)
SageMath is a free open-source mathematics software system. The Pacific Institute for the Mathematical Sciences (PIMS), a consortium of Canadian universities, provides infrastructure and hosting for SageMath and has been a key institutional backer of open mathematical software in Canada.
Axiom
Axiom is a free, open-source computer algebra system with a long history. Canadian mathematicians supported through NSERC (Natural Sciences and Engineering Research Council) have contributed significantly to its formal mathematics libraries and documentation.