diff --git a/extern/poshlib/posh.h b/extern/poshlib/posh.h
index 9586402..b68dcae 100644
--- a/extern/poshlib/posh.h
+++ b/extern/poshlib/posh.h
@@ -306,6 +306,11 @@ LLVM:
 #  define POSH_OS_STRING "FreeBSD"
 #endif
 
+#if defined __OpenBSD__
+#  define POSH_OS_OPENBSD 1
+#  define POSH_OS_STRING "OpenBSD"
+#endif
+
 #if defined __CYGWIN32__
 #  define POSH_OS_CYGWIN32 1
 #  define POSH_OS_STRING "Cygwin"
diff --git a/src/nvcore/Debug.cpp b/src/nvcore/Debug.cpp
index 2dc22dc..25c93a8 100644
--- a/src/nvcore/Debug.cpp
+++ b/src/nvcore/Debug.cpp
@@ -6,6 +6,8 @@
 
 #include "StdStream.h" // fileOpen
 
+#include <stdlib.h>
+
 // Extern
 #if NV_OS_WIN32 //&& NV_CC_MSVC
 #   define WIN32_LEAN_AND_MEAN
@@ -38,7 +40,7 @@
 #   include <signal.h>
 #endif
 
-#if NV_OS_LINUX || NV_OS_DARWIN || NV_OS_FREEBSD
+#if NV_OS_UNIX
 #   include <unistd.h> // getpid
 #endif
 
@@ -49,10 +51,13 @@
 #   endif
 #endif
 
-#if NV_OS_DARWIN || NV_OS_FREEBSD
+#if NV_OS_DARWIN || NV_OS_FREEBSD || NV_OS_OPENBSD
 #   include <sys/types.h>
+#   include <sys/param.h>
 #   include <sys/sysctl.h> // sysctl
-#   include <sys/ucontext.h>
+#   if !defined(NV_OS_OPENBSD)
+#       include <sys/ucontext.h>
+#   endif
 #   if defined(HAVE_EXECINFO_H) // only after OSX 10.5
 #       include <execinfo.h> // backtrace
 #       if NV_CC_GNUC // defined(HAVE_CXXABI_H)
@@ -595,6 +600,16 @@ namespace
 #    else
 #      error "Unknown CPU"
 #    endif
+#elif NV_OS_OPENBSD
+#  if NV_CPU_X86_64
+        ucontext_t * ucp = (ucontext_t *)secret;
+        return (void *)ucp->sc_rip;
+#  elif NV_CPU_X86
+        ucontext_t * ucp = (ucontext_t *)secret;
+        return (void *)ucp->sc_eip;
+#  else
+#       error "Unknown CPU"
+#  endif        
 #else
 #  if NV_CPU_X86_64
         // #define REG_RIP REG_INDEX(rip) // seems to be 16
diff --git a/src/nvcore/nvcore.h b/src/nvcore/nvcore.h
index 22b9631..1681550 100644
--- a/src/nvcore/nvcore.h
+++ b/src/nvcore/nvcore.h
@@ -40,6 +40,9 @@
 #elif defined POSH_OS_FREEBSD
 #   define NV_OS_FREEBSD 1
 #   define NV_OS_UNIX 1
+#elif defined POSH_OS_OPENBSD
+#   define NV_OS_OPENBSD 1
+#   define NV_OS_UNIX 1
 #elif defined POSH_OS_CYGWIN32
 #   define NV_OS_CYGWIN 1
 #elif defined POSH_OS_MINGW
@@ -242,7 +245,7 @@ NV_COMPILER_CHECK(sizeof(uint32) == 4);
 #elif NV_CC_GNUC
 #   if NV_OS_LINUX
 #       include "DefsGnucLinux.h"
-#   elif NV_OS_DARWIN || NV_OS_FREEBSD
+#   elif NV_OS_DARWIN || NV_OS_FREEBSD || NV_OS_OPENBSD
 #       include "DefsGnucDarwin.h"
 #   elif NV_OS_MINGW
 #       include "DefsGnucWin32.h"
diff --git a/src/nvmath/nvmath.h b/src/nvmath/nvmath.h
index 7416662..91d9c43 100644
--- a/src/nvmath/nvmath.h
+++ b/src/nvmath/nvmath.h
@@ -132,7 +132,7 @@ namespace nv
     {
 #if NV_OS_WIN32 || NV_OS_XBOX
         return _finite(f) != 0;
-#elif NV_OS_DARWIN || NV_OS_FREEBSD
+#elif NV_OS_DARWIN || NV_OS_FREEBSD || NV_OS_OPENBSD
         return isfinite(f);
 #elif NV_OS_LINUX
         return finitef(f);
@@ -147,7 +147,7 @@ namespace nv
     {
 #if NV_OS_WIN32 || NV_OS_XBOX
         return _isnan(f) != 0;
-#elif NV_OS_DARWIN || NV_OS_FREEBSD
+#elif NV_OS_DARWIN || NV_OS_FREEBSD || NV_OS_OPENBSD
         return isnan(f);
 #elif NV_OS_LINUX
         return isnanf(f);
diff --git a/src/nvthread/nvthread.cpp b/src/nvthread/nvthread.cpp
index 8e4adbc..b931bfa 100644
--- a/src/nvthread/nvthread.cpp
+++ b/src/nvthread/nvthread.cpp
@@ -5,23 +5,11 @@
 #include "Thread.h"
 
 #if NV_OS_WIN32
-#include "Win32.h"
+#  include "Win32.h"
 #elif NV_OS_UNIX
-#include <sys/types.h>
-#include <sys/sysctl.h>
-#elif NV_OS_DARWIN
-#import <stdio.h>
-#import <string.h>
-#import <mach/mach_host.h>
-#import <sys/sysctl.h>
-
-//#include <CoreFoundation/CoreFoundation.h>
-
-#include <assert.h>
-#include <errno.h>
-#include <stdlib.h>
-#include <string.h>
-#include <syslog.h>
+#  include <sys/types.h>
+#  include <sys/param.h>
+#  include <sys/sysctl.h>
 #endif
 
 using namespace nv;
@@ -39,14 +27,19 @@ uint nv::hardwareThreadCount() {
     return 3; // or 6?
 #elif NV_OS_LINUX // Linux, Solaris, & AIX
     return sysconf(_SC_NPROCESSORS_ONLN);
-#elif NV_OS_DARWIN || NV_OS_FREEBSD
+#elif NV_OS_DARWIN || NV_OS_FREEBSD || NV_OS_OPENBSD
     int numCPU;
     int mib[4];
     size_t len = sizeof(numCPU); 
 
     // set the mib for hw.ncpu
     mib[0] = CTL_HW;
-    mib[1] = HW_AVAILCPU;  // alternatively, try HW_NCPU;
+
+#if NV_OS_OPENBSD
+    mib[1] = HW_NCPU;
+#else
+    mib[1] = HW_AVAILCPU;
+#endif
 
     // get the number of CPUs from the system
     sysctl(mib, 2, &numCPU, &len, NULL, 0);