diff --git a/Unix/base/user.c b/Unix/base/user.c
index 911cee38e..09b78aac0 100644
--- a/Unix/base/user.c
+++ b/Unix/base/user.c
@@ -73,7 +73,7 @@ static int GetGroupName(
 
 static int _authCallback(
     int numMessages,
-#if defined(CONFIG_OS_LINUX) || defined(CONFIG_OS_DARWIN) || defined(CONFIG_OS_BSD)
+#if defined(CONFIG_OS_LINUX) || defined(CONFIG_OS_DARWIN) || defined(CONFIG_OS_BSD) || defined(CONFIG_OS_FREEBSD)
     const struct pam_message** messages,
 #else
     struct pam_message** messages,
@@ -766,7 +766,7 @@ MI_Boolean ValidateGssCredentials(const char *credFilePath, const char *krb5KeyT
 
 }
 
-#if defined(CONFIG_OS_LINUX) || defined(CONFIG_OS_DARWIN)
+#if defined(CONFIG_OS_LINUX) || defined(CONFIG_OS_DARWIN) || defined(CONFIG_OS_FREEBSD)
 static int _SearchPermissionGroups(PermissionGroups *list, gid_t gid)
 {
     PermissionGroup *group = list->head;
@@ -829,7 +829,7 @@ int IsUserAuthorized(const char *user, gid_t gid)
     int ngroups = MAX_GROUPS;
     int i;
 
-#if defined(CONFIG_OS_LINUX) || defined(CONFIG_OS_DARWIN)
+#if defined(CONFIG_OS_LINUX) || defined(CONFIG_OS_DARWIN) || defined(CONFIG_OS_FREEBSD)
     // get list of groups that user belongs to
     if (getgrouplist(user, gid, groups, &ngroups) == -1)
     {
diff --git a/Unix/buildtool b/Unix/buildtool
index c3e48796a..b639a840e 100755
--- a/Unix/buildtool
+++ b/Unix/buildtool
@@ -273,14 +273,21 @@ if [ -z "$target" ]; then
             compiler=GNU
             distro=`lsb_release -i | awk -F":" '{ print $2 }'`
             distro_version=`lsb_release -r | awk -F":" '{ print $2 }'`
-	    ;;
+            ;;
         arm*:Linux:*)
             os=LINUX
             arch=ARM
             compiler=GNU
             distro=`lsb_release -i | awk -F":" '{ print $2 }'`
             distro_version=`lsb_release -r | awk -F":" '{ print $2 }'`
-	    ;;
+            ;;
+        amd64:FreeBSD:*:*)
+            os=FREEBSD
+            arch=X86_64
+            compiler=GNU
+            distro=`uname -s`
+            distro_version=`sysctl -n kern.osrelease | cut -f1 -d'-'`
+            ;;
         *)
             echo "$0: error: unsupported platform: $__m:$__s:$__r:$__v"
             exit 1
@@ -329,7 +336,7 @@ case "$platform" in
         compiler_minor_version=`echo $compiler_version | awk -F' ' '{ print $5}' | awk -F"." '{ print $2}'`
         compiler_revision=`echo $compiler_version | awk -F' ' '{ print $5}' | awk -F"." '{ print $3}'`
         ;;
-    DARWIN_IX86_GNU)
+    DARWIN_IX86_GNU|FREEBSD_X86_64_GNU)
         compiler_version=`clang --version | awk -F" " 'match($0, /version [0-9]*\.[0-9]*\.[0-9]*/){ print $4 }'`
         compiler_major_version=`echo $compiler_version | awk -F'.' '{ print $1}'`
         compiler_minor_version=`echo $compiler_version | awk -F'.' '{ print $2}'`
@@ -438,7 +445,7 @@ if [ "$arg1" = "longhostname" ]; then
         MONTAVISTA*)
             hostname
             ;;
-        NETBSD*)
+        NETBSD*|FREEBSD*)
             hostname
             ;;
         DARWIN*)
@@ -594,6 +601,9 @@ if [ "$arg1" = "cc" ]; then
         DARWIN_IX86_GNU)
             echo clang
             ;;
+        FREEBSD_X86_64_GNU)
+            echo clang
+            ;;
     esac
 
     exit
@@ -635,6 +645,9 @@ if [ "$arg1" = "cxx" ]; then
         DARWIN_IX86_GNU)
             echo clang++
             ;;
+        FREEBSD_X86_64_GNU)
+            echo clang++
+            ;;
     esac
 
     exit
@@ -714,6 +727,9 @@ if [ "$arg1" = "size" ]; then
         DARWIN_IX86_GNU)
             echo size
             ;;
+        FREEBSD_X86_64_GNU)
+            echo size
+            ;;
 	*)
 	    echo "echo \'Unsuported platform: $platform\'"
 	    exit 1
@@ -927,6 +943,20 @@ if [ "$arg1" = "cflags" -o "$arg1" = "cxxflags" ]; then
             r="$r -fstack-protector-all"
             r="$r -DGSS_USE_IOV=1"
             ;;
+        FREEBSD_X86_64_GNU)
+            test -z "$debug_opt" && r="$r -O2"
+            test -n "$pic_opt" && r="$r -fPIC"
+            ## treat warnings as errors.
+            test -n "$errwarn_opt" && r="$r -Werror"
+            r="$r -Wall"
+            r="$r -I/usr/local/include"
+            r="$r -Dfreebsd -D__BSD_VISIBLE=1 -DPAL_NO_ALLOCA=1"
+            r="$r -fstack-protector-all"
+            r="$r -fno-strict-aliasing"
+            r="$r -D_GNU_SOURCE"
+            r="$r -D_XOPEN_SOURCE=700"
+            r="$r -DGSS_USE_IOV=1"
+            ;;
     esac
 
     echo $r
@@ -984,6 +1014,9 @@ if [ "$arg1" = "cshlibflags" -o "$arg1" = "cxxshlibflags" ]; then
             ;;
         NETBSD_IX86_GNU)
             r="$r -shared"
+            ;;
+        FREEBSD_X86_64_GNU)
+            r="$r -shared -fuse-ld=lld"
             test -n "$libpath_opt" && r="$r -Wl,-rpath=$libpath_opt"
             ;;
         SUNOS_I86PC_SUNPRO|SUNOS_SPARC_SUNPRO)
@@ -1104,7 +1137,8 @@ if [ "$arg1" = "cprogflags" -o "$arg1" = "cxxprogflags" ]; then
         MONTAVISTA_IX86_GNU)
             test -n "$libpath_opt" && r="$r -Wl,-rpath=$libpath_opt"
             ;;
-        NETBSD_IX86_GNU)
+        NETBSD_IX86_GNU|FREEBSD_X86_64_GNU)
+            r="$r -fuse-ld=lld"
             test -n "$libpath_opt" && r="$r -Wl,-rpath=$libpath_opt"
             ;;
         SUNOS_I86PC_SUNPRO|SUNOS_SPARC_SUNPRO)
@@ -1231,7 +1265,7 @@ if [ "$arg1" = "syslibs" ]; then
         MONTAVISTA_IX86_GNU)
             r="-lpthread -ldl -lpam"
             ;;
-        NETBSD_IX86_GNU)
+        NETBSD_IX86_GNU|FREEBSD_X86_64_GNU)
             r="-lpthread -ldl -lpam"
             ;;
         SUNOS_I86PC_SUNPRO|SUNOS_SPARC_SUNPRO)
@@ -1285,7 +1319,7 @@ if [ "$arg1" = "libpath" ]; then
                 r="$r -Wl,-rpath=$path"
             done
             ;;
-        NETBSD_IX86_GNU)
+        NETBSD_IX86_GNU|FREEBSD_X86_64_GNU)
             for path in $args
             do
                 r="$r -Wl,-rpath=$path"
@@ -1447,7 +1481,7 @@ if [ "$arg1" = "shlibname" ]; then
         MONTAVISTA_IX86_GNU)
             echo "lib$arg2.so"
             ;;
-        NETBSD_IX86_GNU)
+        NETBSD_IX86_GNU|FREEBSD_X86_64_GNU)
             echo "lib$arg2.so"
             ;;
         SUNOS_I86PC_SUNPRO|SUNOS_SPARC_SUNPRO)
@@ -1491,7 +1525,7 @@ if [ "$arg1" = "shlibext" ]; then
         MONTAVISTA_IX86_GNU)
             echo "so"
             ;;
-        NETBSD_IX86_GNU)
+        NETBSD_IX86_GNU|FREEBSD_X86_64_GNU)
             echo "so"
             ;;
         SUNOS_I86PC_SUNPRO|SUNOS_SPARC_SUNPRO)
@@ -1612,6 +1646,11 @@ if [ "$arg1" = "openssllibdir" ]; then
                     libdir=/usr/lib
                 fi
                 ;;
+            FREEBSD_X86_64_GNU)
+                if [ -f "/usr/lib/libssl.so" ]; then
+                    libdir=/usr/lib
+                fi
+                ;;
             *)
                 echo "so"
         esac
@@ -1967,6 +2006,9 @@ if [ "$arg1" = "gssapi_ext" ]; then
             DARWIN)
                     echo "0"
                     ;;
+            FREEBSD)
+                    echo "1"
+                    ;;
                 *)
                     # not-supported!
                     echo "0"
diff --git a/Unix/configure b/Unix/configure
index 9c3ccb7e0..ec6c8c827 100755
--- a/Unix/configure
+++ b/Unix/configure
@@ -1433,6 +1433,14 @@ case $os in
                 krblibpath=/System/Library/Frameworks/Kerberos.framework/Kerberos
             fi
             ;;
+        FREEBSD)
+            if [ disable_auth != 1 ]
+            then
+                gsslib=gssapi_krb5
+                gsslibpath=libgssapi_krb5.so
+                krblibpath=libkrb5.so
+            fi
+            ;;
         *)
             echo "Unknown platform: " $os
             exit 1
@@ -1509,6 +1517,9 @@ if [ "$os" = "DARWIN" ]; then
             exit 1
         fi
     fi
+elif [ "$os" = "FREEBSD" ]; then
+    openssllibdir="/usr/lib"
+    openssllibs="-L$openssllibdir -lssl -lcrypto -lz"
 else
     if [ "$opensslcflags_found" != "1" ]; then
         opensslcflags=`$pkgconfig --cflags openssl`
@@ -2570,7 +2581,7 @@ case $os in
                 cp $root/scripts/installpam-sun9 $fn.tmp
             fi
             ;;
-        Darwin)
+        Darwin|FreeBSD)
             cp $root/scripts/installpam-rhel $fn.tmp
             ;;
         *)
diff --git a/Unix/miapi/SafeHandle.c b/Unix/miapi/SafeHandle.c
index 095defac2..2ef22e7b9 100644
--- a/Unix/miapi/SafeHandle.c
+++ b/Unix/miapi/SafeHandle.c
@@ -7,7 +7,7 @@
 **==============================================================================
 */
 
-#if !defined(macos)
+#if !defined(macos) && !defined(freebsd)
 #include <malloc.h>
 #endif
 #include <MI.h>
diff --git a/Unix/micxx/atomic.h b/Unix/micxx/atomic.h
index 651a7e997..688b0a207 100644
--- a/Unix/micxx/atomic.h
+++ b/Unix/micxx/atomic.h
@@ -14,7 +14,7 @@
 
 MI_BEGIN_NAMESPACE
 
-#if !defined(macos)
+#if !defined(macos) && !defined(freebsd)
 typedef struct _Atomic
 #else
 typedef struct _AtomicType
diff --git a/Unix/nits/base/Run.h b/Unix/nits/base/Run.h
index c001d78ad..58ae7ddc6 100644
--- a/Unix/nits/base/Run.h
+++ b/Unix/nits/base/Run.h
@@ -178,7 +178,7 @@ class Run
     bool m_finished;            //Stops pipe thread.
 
     int *m_statistics;
-#if !defined(macos) // Mac says this is not used
+#if !defined(macos) && !defined(freebsd) // Mac and FreeBSD says this is not used
     int m_faultIterations;      //Cumulative fault injection iteration total.
 #endif
 
diff --git a/Unix/omi_error/omierror.c b/Unix/omi_error/omierror.c
index d07b12868..090a4a8bc 100644
--- a/Unix/omi_error/omierror.c
+++ b/Unix/omi_error/omierror.c
@@ -332,7 +332,7 @@ MI_INLINE const MI_Char *Errno_ToString(
     _Out_writes_z_(len) MI_Char *buffer,
     MI_Uint32 len)
 {
-#if defined(macos) || ((_POSIX_C_SOURCE >= 200112L || _XOPEN_SOURCE >= 600) && ! _GNU_SOURCE)
+#if defined(macos) || defined(freebsd) || ((_POSIX_C_SOURCE >= 200112L || _XOPEN_SOURCE >= 600) && ! _GNU_SOURCE)
         int ret = strerror_r(OMI_Code, buffer, len);
         if (ret != 0)
             *buffer = '\0';
diff --git a/Unix/pal/cpu.c b/Unix/pal/cpu.c
index 5adff123e..9e48f4aab 100644
--- a/Unix/pal/cpu.c
+++ b/Unix/pal/cpu.c
@@ -10,6 +10,27 @@
 #include <sys/time.h>
 #include "cpu.h"
 
+#if defined(CONFIG_OS_FREEBSD)
+long timezone_calculated = 0;
+
+__attribute__((constructor)) static void InitializeTimeOffset(void)
+{
+    // Unlike SYSV, BSD does not have timezone with time offset. (It returns char* with name)
+    // We need to calculate it once.
+    struct tm gmt;
+    struct tm local;
+
+    time_t now = time(NULL);
+    // Calculate GMT and local time
+    gmtime_r(&now, &gmt);
+    localtime_r(&now, &local);
+
+    // calculate difference between local time and GMT
+    // Since it is only used on one place, pre-calculate to minutes.
+    timezone_calculated = (mktime(&gmt) - mktime(&local)) / -60;
+}
+#endif
+
 _Success_(return == 0)
 int CPU_GetLocalTimestamp(
     _Out_ PAL_Datetime* current)
@@ -28,7 +49,11 @@ int CPU_GetLocalTimestamp(
     current->u.timestamp.minute = tm.tm_min;
     current->u.timestamp.second = tm.tm_sec;
     current->u.timestamp.microseconds = tv.tv_usec;
+#if defined(CONFIG_OS_FREEBSD)
+    current->u.timestamp.utc = timezone_calculated;
+#else
     current->u.timestamp.utc = -timezone / 60;
+#endif
     return 0;
 }
 
diff --git a/Unix/pal/palcommon.h b/Unix/pal/palcommon.h
index de0800373..21b9d00e0 100644
--- a/Unix/pal/palcommon.h
+++ b/Unix/pal/palcommon.h
@@ -219,7 +219,7 @@ typedef PAL_Char TChar;
 **==============================================================================
 */
 
-#if defined(linux) || defined(sun) || defined(hpux) || defined(aix) || defined(macos)
+#if defined(linux) || defined(sun) || defined(hpux) || defined(aix) || defined(macos) || defined(freebsd)
 # define PAL_HAVE_POSIX
 #endif
 
@@ -231,7 +231,7 @@ typedef PAL_Char TChar;
 **==============================================================================
 */
 
-#if defined(linux) | defined(sun) | defined(hpux) | defined(aix) | defined(macos)
+#if defined(linux) | defined(sun) | defined(hpux) | defined(aix) | defined(macos) | defined(freebsd)
 # define PAL_HAVE_PTHREADS
 #endif
 
diff --git a/Unix/pal/thread.h b/Unix/pal/thread.h
index ebc498d2a..76ac4d800 100644
--- a/Unix/pal/thread.h
+++ b/Unix/pal/thread.h
@@ -79,6 +79,10 @@ int Thread_Equal(
 
 ThreadID Thread_ID();
 
+#if defined(freebsd)
+int pthread_getthreadid_np(void);
+#endif
+
 PAL_INLINE
 PAL_Uint64 Thread_TID()
 {
@@ -88,6 +92,8 @@ PAL_Uint64 Thread_TID()
     __uint64_t threadid;
     pthread_threadid_np(pthread_self(), &threadid);
     return threadid;
+#elif defined(freebsd)
+    return (PAL_Uint64)pthread_getthreadid_np();
 #else
     // Avoid using a cast here since pthread_self() may return a structure.
     // If so, we need to discover that and provide an alternative for that