NextBSD reboot aims to bring Darwin components back to FreeBSD

NextBSD, the BSD variant started in 2015 by FreeBSD co-founder Jordan Hubbard, is being restarted by developer Joe Maloney with a new codebase and project organization. The revived effort aims to pair the FreeBSD kernel with selected open source components from Apple’s Darwin stack, a technically hard project with no disclosed funding, headcount beyond Maloney, release date or commercial plan.

Maloney, known on GitHub as pkgdemon, previously built the Gershwin desktop work used in GhostBSD. He had a small role in the original NextBSD project, and after working on Gershwin he asked the maintainers whether he could take over NextBSD, according to The Register. The new NextBSD repository is separate from the old project repository, which remains online but has not seen changes for seven years. The revived project also publishes a history page crediting the earlier team.

The premise has not changed much. Darwin is the Unix-based foundation under macOS, iOS, watchOS and tvOS, and Apple publishes substantial parts of it as open source. Those components include the XNU kernel, launchd, IOKit, Apple System Log and related system software. NextBSD is not trying to run Apple’s kernel on commodity PC hardware. Its plan is to keep FreeBSD as the base kernel and bring over relevant Darwin userland pieces and glue code where they can fit.

That distinction matters because prior attempts to turn Darwin itself into a broadly usable PC operating system have struggled. OpenDarwin began in 2002 and shut down in 2006. PureDarwin later produced releases in 2015 and 2019 and was maintained as recently as 2024. Other projects, including GNU Darwin and DarwinBSD, also tried variants of the idea. The common problem is that Apple’s lower-level OS work is built for Apple hardware even when parts of the code are public.

The current NextBSD-redux README and porting notes describe work in progress rather than a finished operating system. There is no graphical desktop yet, though Maloney is also working on Gershwin for NextBSD. Gershwin itself combines GNUstep components, the Xfce window manager and other software to produce a Mac-like desktop environment.

The reboot also borrows from adjacent projects. The new NextBSD uses some libraries carried by ravynOS, including libxpc, which originated in the original NextBSD project. RavynOS has its own macOS-like ambitions and, according to its earlier FAQ, had worked with helloSystem, a FreeBSD-based desktop OS effort led by Simon Peter, the creator of AppImage. Peter later moved to help with Gershwin development.

Maloney disclosed another unusual part of the project: Anthropic’s Claude Code is listed alongside him in the project’s team section. He told The Register that AI is acting as his “team of developers,” while he steers the work and reviews changes. He also said he understands objections to AI-generated code, especially in production environments without human review.

Although the public nextbsd-redux commits are only a couple of months old, Maloney told The Register the work went through earlier iterations in his personal GitHub account. He said the first pass tested whether a sockets-only version of launchd could work without Mach. A second iteration focused on a Mach kernel module and launchd, adding pieces such as libxpc. The third split the work into separate repositories, moved builds into GitHub and added automated tests.

For now, NextBSD is an experimental integration project rather than a usable OS distribution. Its progress will depend less on branding around Apple-like software and more on whether Maloney can make Darwin services, FreeBSD internals and borrowed compatibility layers behave as one maintainable system.

This story draws on original reporting from The Register.