An open-source IDE for the Eiffel programming language

Eiffel Studio
Free
Offline
https://dev.eiffel.com/Main_Page

EiffelStudio is an open-source IDE for the Eiffel programming language. Eiffel Software is the principal contributor and hosts the subversion repository. EiffelStudio is maintained and developed by Eiffel Software as well many contributors, including ETH Zurich.