OpenBSD source code:Browse the complete OpenBSD CVS source repository via web.
BSD Sockets: A Quick And Dirty Primer: Crash course in programming BSD sockets
Building an OpenBSD port: Information on porting software to OpenBSD.
Experimental OpenBSD Ports: Unofficial OpenBSD ports and packages of Qmail, Djbdns and other Unix software.
Modula-3: Information on compiling and running Modula-3 on OpenBSD.
OpenBSD - owc / odc: Mailing lists hosted by Squish.net that collate the OpenBSD source-changes and email summary reports daily or weekly.
OpenBSD commit stats: Statistics on the number, type, and originator of commits to the OpenBSD CVS repository.
OpenBSD kernel source tour: Hypertext markup of the OpenBSD 2.3 kernel sources.
Porting audio applications to OpenBSD: Reference information regarding porting audio software to OpenBSD.
Porting BSD UNIX to a New Platform: Paper discussing what is entailed in porting the BSD codebase to a new architecture.
Porting Zzipp to OpenBSD: Instructions about how the 'Zzipp.3.1.01' application was ported to OpenBSD.
PPP userland tools: Latest docs and sources for userland PPP for OpenBSD.
PPPoE: Code for PPP over Ethernet. Now included in the OpenBSD source tree as of 2.8 Release.
strlcpy and strlcat--Consistent, Safe, String Copy and Concatenation: Whitepaper by OpenBSD developers Todd C. Miller and Theo de Raadt discussing secure programming functions for manipulating strings.
The Kame Project: Project to develop IPv6 & IPsec stack for use in BSD-based operating systems. Included in the OpenBSD sources since OpenBSD 2.7 Release.
Unofficial OpenBSD pathces: List of unofficial OpenBSD pathces done by Sergey Smitienko.