diff --git a/share/man/man1/intro.1 b/share/man/man1/intro.1
--- a/share/man/man1/intro.1
+++ b/share/man/man1/intro.1
@@ -85,6 +85,7 @@
 .Xr which 1 ,
 .Xr intro 2 ,
 .Xr intro 3 ,
+.Xr intro 3lua ,
 .Xr sysexits 3 ,
 .Xr intro 4 ,
 .Xr intro 5 ,
diff --git a/share/man/man3lua/Makefile b/share/man/man3lua/Makefile
--- a/share/man/man3lua/Makefile
+++ b/share/man/man3lua/Makefile
@@ -1,5 +1,7 @@
 .include <src.opts.mk>
 
-MAN=	intro.3lua
+MAN=	freebsd.3lua	\
+	intro.3lua	\
+	posix.3lua
 
 .include <bsd.prog.mk>
diff --git a/share/man/man3lua/intro.3lua b/share/man/man3lua/intro.3lua
--- a/share/man/man3lua/intro.3lua
+++ b/share/man/man3lua/intro.3lua
@@ -24,32 +24,31 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.Dd October 24, 2020
+.Dd September 5, 2024
 .Dt INTRO 3lua
 .Os
 .Sh NAME
 .Nm intro
-.Nd introduction to the Lua modules for flua
+.Nd introduction to flua
 .Po
 .Fx
 Lua
 .Pc
 .Sh DESCRIPTION
-This section describes
-.Em flua
-.Po
-.Fx
-Lua
-.Pc
-and the Lua modules provided in the
+.Nm
+is a Lua 5.4 interpreter which is available for use in the
 .Fx
-base system.
+base system, via
+.Pa /usr/libexec/flua .
+It provides a number of FreeBSD-specific modules.
 .Pp
 The Lua modules provided by
 .Fx
 are:
 .Bl -tag -width jail
+.It Xr freebsd 3lua
 .It Xr jail 3lua
+.It Xr posix 3lua
 Wrapper for
 .Xr jail 3 .
 .El
diff --git a/share/man/man3lua/posix.3lua b/share/man/man3lua/posix.3lua
new file mode 100644
--- /dev/null
+++ b/share/man/man3lua/posix.3lua
@@ -0,0 +1,89 @@
+.\"
+.\" SPDX-License-Identifier: BSD-2-Clause
+.\"
+.\" Copyright (c) 2024 Mark Johnston <markj@FreeBSD.org>
+.\"
+.Dd September 5, 2024
+.Dt POSIX 3lua
+.Os
+.Sh NAME
+Lua bindings for POSIX interfaces
+.Sh SYNOPSIS
+.Bl -tag -width XXXX -compact
+.It Dv pid, err, errno = posix.spawn.posix_spawn(path, [file_actions,] [attrs,] args[, env])
+.It Dv pid, err, errno = posix.spawn.posix_spawnp(file, [file_actions,] [attrs,] args[, env])
+
+.It Dv ok, err, errno = posix.stat.chmod(path, mode)
+
+.It Dv utsname, err, errno = posix.sys.utsname.uname()
+
+.It Dv ok, err, errno = posix.unistd.chown(path, user, group)
+.It Dv ok, err, errno = posix.unistd.close(fd)
+.It Dv pid = posix.unistd.getpid()
+.It Dv fd1, fd2 = posix.unistd.pipe()
+.El
+.Sh DESCRIPTION
+The
+.Nm posix
+module provides bindings for various standard
+.Xr c 7
+interfaces provided by
+.Fx .
+This implementation aims to be compatible with the luaposix project.
+The namespace is partitioned by the names of C headers located in
+.Pa /usr/include
+and
+.Pa /usr/include/sys .
+.Pp
+These bindings generally correspond to individual C functions or constants
+and for the most do not implement functionality directly, except when doing
+so is convenient.
+For example, the
+.Fa user
+and
+.Fa group
+parameters for
+.Fn posix.unistd.chown
+can be integers corresponding to the desired user and group ID, as they must
+be for the
+.Xr chown 2
+system call, but they may instead be strings, in which case
+.Fn posix.unistd.chown
+will use
+.Xr getpwnam_r 3
+and
+.Xr getgrnam_r 3
+to resolve them to integer identifiers before calling
+.Xr chown 2 .
+.Pp
+The
+.Nm
+module defines a userdata type to represent a file descriptor,
+as returned or consumed by many functions in this module.
+The flua garbage collector will automatically close descriptors
+that are no longer in use, so descriptors can not be leaked.
+However, the garbage collector does not ensure that unreferenced
+descriptors are closed within any particular time frame.
+It may thus be necessary to manually close descriptors using
+.Fn posix.unistd.close .
+.Sh RETURN VALUES
+Functions in this module follow a convention of returning a
+non-nil value if the function call was successful, and a 3-tuple
+of nil, the error string, and an 
+.Xr errno 2
+value, if the call failed.
+.Sh EXAMPLES
+Retrieve system identifiers using
+.Xr uname 3
+and print them:
+.Bd -literal -offset indent
+local uts, err = posix.sys.utsname.uname()
+if not uts then
+    error("uname failed: " .. err)
+end
+for k, v in pairs(uts) do
+    print(k .. ": " .. v)
+end
+.Ed
+.Sh SEE ALSO
+.Xr intro 3lua