The GNOME Project has announced a few days ago the immediate availability for download and testing of the third development release towards GNOME Calculator 3.12, which introduces new features, fixes bugs and updates translations.
GNOME Calculator 3.11.3 introduces new custom functions, adds support for factorials of positive decimal numbers, uses HeaderBar, and depends on the latest releases of Vala and GTK+.
Moreover, GNOME Calculator 3.11.3 no longer uses stock icons, repairs various compilation warning, fixes the title in basic mode, repairs the newline text wrap bug, finally fixes the "Malformed expression" bug, and fixes some typos and AppData. More details can be found in the official raw changelog.
Download GNOME Calculator 3.11.3 right now from Softpedia. Remember that this is a development release and it should NOT be installed on production machines. It is intended to be used for testing purposes only.