FreeNT is an experimental, open-source full userland replacement for
Windows NT. It provides its own implementations of the user-mode components
that Microsoft ships in %SystemRoot%\System32 — including the Win32
subsystem DLLs (kernel32, user32, gdi32), the session manager (smss), the
Windows subsystem (csrss/winlogon), the service control manager, and the
graphical shell (explorer) — plus a Tiny C Runtime (FreeDLL) and a PE dynamic
linker (NTDYLIB).
The userland is written in freestanding C: it has no C
runtime, or dependency on the proprietary Microsoft kernel32.dll,
ucrtbase.dll, or msvcrt.dll. All components import only ntdll.dll for
actual NT kernel system calls. The kernel and essential boot drivers remain
Microsoft-provided; everything above them is FreeNT.
- FreeDLL now exposes additional ANSI C allocation, search, pseudo-random, and string-set primitives for freestanding Native Mode programs.
- NTVM provides a FreeDLL-backed real-mode
.COMloader and CPU context contract, forming the portable host boundary for an NTVDM-style interpreter. - NTTTY supplies BSD/POSIX-like termios state, canonical/raw line disciplines, terminal buffers, and process-group controls for Native Mode.