We make Rutba Office, a free, open-source office suite for Windows, and Rutba, business software on one account. We are also working on Paritas, an Oracle-compatible PostgreSQL that tells you where the compatibility ends.
Happy to talk about office file formats and Oracle migrations.
https://office.rutba.io/
https://github.com/eharain/Rutba-Office
https://tech-style.co/