osFree project does not aim to rewrite everything from scratch. We realize that our resources are limited. So, we must reuse existing code as much as possible. We have already taken a number of FOSS and Public domain software as a base of our OS components. Here is their list (may be, incomplete, sorry if it is).

Much thanks to those projects: (software or documentation)

• Regina REXX - our Classic REXX replacement
• THE - our TEDIT replacement
• And lot of other things from Mark Hessling. His products allowed us not to reinvent the wheel.
• OS2Linux project as a base for CPI implementation on top of Fiasco microkernel.
• FreePM project as base of PM reimplementation
• DROPS as base of most Personality Neutral Servers.
• L4Linux as Linux personality core.
• osFree/CMD project as base for most of command line tools
• FreeLDR project which was evolved in full featured kernel loader.
• GRUB which was good codebase for FreeLDR project.
• MCPP used as SOM CPP base.
• somFree used as SOM replacement base
• GBM used as core of Image Format I/O Procedures
• JPGIO used as core of Image Format I/O Procedures
• ZLIB used in many parts
• LIBPNG used in many parts
• LIBJPEG used in many parts
• GDLIB used in FreePM
• LIBTIFF used in many parts
• Fiasco reused as microkernel
• PParser from FPK used as UNI2H tool base
• TWIN library as win16 base
• MINSTALL by Martin Kiewitz
• MMImage Pak as Image File Format I/O Procedures
• MMAudio Pak 2 as Audio File Format I/O Procedures
• FreeDOS parts as DOS subsystem base
• Ralf Brown documentation (Interrupt list). Great source of DOS and DOS VM information.
• ALVM
• LVMPM
• LVMTK
• HX DOS Extender
• CWMM Classes
• Open Watcom
• JWasm
• ACPITK
• XWPHelpers
• 4os2
• XWorkplace
• Wine
• ReactOS

and other projects here. Please add it if we missed one.