V7/x86 is a port of the Seventh Edition of the UNIX operating system to the x86 (IA-32) based PC. UNIX V7 was the last general distribution (around 1979) to come from the Research group at Bell Labs, the original home of UNIX. The port was done mostly around 1999 when "Ancient UNIX" source code licenses first became available, and was revised for release, with some enhancements, during 2006-7.
The distribution includes the full UNIX Version 7 operating system, with source code, pre-built binaries, man pages, and original Version 7 documentation. Also included are a custom UNIX-style x86 assembler, an ACK-based C compiler, and several key early UCB software components such as the C shell, the editors ex and vi, and the pager more.
V7/x86 currently supports ATA (IDE) hard drives, ATAPI CDROM drives, a 1.44M floppy drive, and standard serial ports, in addition to the usual PC screen and keyboard. For easier installation and setup, supplied utilities allow access to CD (ISO 9660) and FAT (MS-DOS) filesystems. Source code is available under a Berkeley-style license.

This directory contains the files needed to build a clean unix v6
installation from tape.  It requires that you have "expect" and
simh's "pdp11" and "wget" installed in your path.

Capsicum is a lightweight OS capability and sandbox framework developed at the University of Cambridge Computer Laboratory, supported by grants from Google, the the FreeBSD Foundation, and DARPA. Capsicum extends the POSIX API, providing several new OS primitives to support object-capability security on UNIX-like operating systems:

   capabilities - refined file descriptors with fine-grained rights
   capability mode - process sandboxes that deny access to global namespaces
   process descriptors - capability-centric process ID replacement
   anonymous shared memory objects - an extension to the POSIX shared memory API to support anonymous swap objects associated with file descriptors (capabilities)
   rtld-elf-cap - modified ELF run-time linker to construct sandboxed applications
   libcapsicum - library to create and use capabilities and sandboxed components
   libuserangel - library allowing sandboxed applications or components to interact with user angels, such as Power Boxes.
   chromium-capsicum - a version of Google's Chromium web browser that uses capability mode and capabilities to provide effective sandboxing of high-risk web page rendering.

Unix History Repository

The goal of this project is to create a git repository representing the Unix source code history, starting from the 1970s and ending in the modern time. To fulfill this goal the project brings data from early snapshots, repositories, and primary research. The project aims to put in the repository as much metadata as possible, allowing the automated analysis of Unix history.

Created by Diomidis Spinellis.

Plan9port, a port of many Plan 9 user programs to Unix used to live on
http://swtch.com/plan9port/, but since 2014-11-17 it has been moved to this git repository.

Interesting comparison between the two operating systems.

Series of blog articles by Will Senn about running v6 unix on SimH.
On 2022-12-08 he migrated the blog to https://decuser.github.io/

Unix philosophy and -programming, in german.

pkgsrc is a framework for building third-party software on NetBSD and other UNIX-like systems, currently containing over 12000 packages. It is used to enable freely available software to be configured and built easily on supported platforms (which include OS X and Cygwin).

Zero Install is a decentralised cross-distribution software installation system. Other features include full support for shared libraries (with a SAT solver for dependency resolution), sharing between users, and integration with native platform package managers. It supports both binary and source packages, and works on Linux, OS X, Unix and Windows systems. It is fully Open Source.