diff --git a/utils/httpd/Makefile b/utils/httpd/Makefile
new file mode 100644
index 0000000..73ff5ec
--- /dev/null
+++ b/utils/httpd/Makefile
@@ -0,0 +1,58 @@
+# httpd-utils
+# Written in 2020 by Lucas
+# CC0 1.0 Universal/Public domain - No rights reserved
+#
+# To the extent possible under law, the author(s) have dedicated all
+# copyright and related and neighboring rights to this software to the
+# public domain worldwide. This software is distributed without any
+# warranty. You should have received a copy of the CC0 Public Domain
+# Dedication along with this software. If not, see
+# <http://creativecommons.org/publicdomain/zero/1.0/>.
+.POSIX:
+.SUFFIXES:
+.SUFFIXES: .c
+
+P =	httpd-utils
+V =	1
+
+DOMAIN =	example.net
+DOMAIN_V4 =	4.${DOMAIN}
+DOMAIN_V6 =	6.${DOMAIN}
+IPV4 =		192.0.2.1
+IPV6 =		2001:db8::2
+PREFIX =	/var/www/htdocs/${DOMAIN}
+
+CGI =	ip
+SRC =	ip.c gen-config.sh gen-index.sh
+TXT =	codes.txt
+
+.c:
+	${CC} ${CFLAGS} ${LDFLAGS} -static -o $@ $<
+
+all: ${DOMAIN}.httpd.conf index.html ${CGI}
+
+${DOMAIN}.httpd.conf: gen-config.sh codes.txt
+	sh gen-config.sh ${DOMAIN} ${DOMAIN_V4} ${IPV4} ${DOMAIN_V6} ${IPV6} >$@
+
+index.html: gen-index.sh codes.txt
+	sh gen-index.sh ${DOMAIN} ${DOMAIN_V4} ${DOMAIN_V6} >$@
+
+clean:
+	rm -f ${DOMAIN}.httpd.conf index.html ${CGI} ${P}-${V}.tgz
+
+dist: clean
+	pax -ws ',^,${P}-${V}/,' Makefile ${SRC} ${TXT} | gzip >${P}-${V}.tgz
+
+install: all
+	cp -f ${DOMAIN}.httpd.conf /etc
+	mkdir -p ${PREFIX}
+	cp -f ${CGI} ${PREFIX}
+	cd ${PREFIX} && chmod 555 ${CGI}
+	cd ${PREFIX} && chown www:www ${CGI}
+	cp -f index.html ${PREFIX}
+	cd ${PREFIX} && chmod 444 index.html
+	cd ${PREFIX} && chown www:www index.html
+
+uninstall:
+	rm -f /etc/${DOMAIN}.httpd.conf
+	cd ${PREFIX} && rm -f ${CGI} index.html
diff --git a/utils/httpd/codes.txt b/utils/httpd/codes.txt
new file mode 100644
index 0000000..b8a67f5
--- /dev/null
+++ b/utils/httpd/codes.txt
@@ -0,0 +1,70 @@
+# Informational 1xx
+100
+101
+102
+
+# Successful 2xx
+200
+201
+202
+203
+204
+205
+206
+207
+208
+226
+
+# Redirection 3xx
+300
+301
+302
+303
+304
+305
+306
+307
+308
+
+# Client Error 4xx
+400
+401
+402
+403
+404
+405
+406
+407
+408
+409
+410
+411
+412
+413
+414
+415
+416
+417
+418
+420
+422
+423
+424
+426
+428
+429
+431
+451
+
+# Server Error 5xx
+500
+501
+502
+503
+504
+505
+506
+507
+508
+510
+511
diff --git a/utils/httpd/gen-config.sh b/utils/httpd/gen-config.sh
new file mode 100644
index 0000000..c355e2f
--- /dev/null
+++ b/utils/httpd/gen-config.sh
@@ -0,0 +1,84 @@
+#!/bin/sh
+# httpd-utils
+# Written in 2020 by Lucas
+# CC0 1.0 Universal/Public domain - No rights reserved
+#
+# To the extent possible under law, the author(s) have dedicated all
+# copyright and related and neighboring rights to this software to the
+# public domain worldwide. This software is distributed without any
+# warranty. You should have received a copy of the CC0 Public Domain
+# Dedication along with this software. If not, see
+# <http://creativecommons.org/publicdomain/zero/1.0/>.
+
+usage()
+{
+	printf "Usage: %s domain domain_v4 ipv4 domain_v6 ipv6\n" "${0##*/}" >&2
+	exit 1
+}
+
+list_codes()
+{
+	case $1 in
+	1xx)	q='1[0-9][0-9]' ;;
+	2xx)	q='2[0-9][0-9]' ;;
+	3xx)	q='3[0-9][0-9]' ;;
+	4xx)	q='4[0-9][0-9]' ;;
+	5xx)	q='5[0-9][0-9]' ;;
+	*)	q=X ;;
+	esac
+	grep -x -- "$q" codes.txt
+}
+
+print_block_return()
+{
+	_c=$1 _l=${2:-}
+
+	_fmt='\tlocation "/c/%u" { block return %u'${_l:+' "%s"'}' }\n'
+	printf "$_fmt" $_c $_c $_l
+}
+
+[ $# -eq 5 ] || usage
+domain=$1 domain_v4=$2 ipv4=$3 domain_v6=$4 ipv6=$5
+
+cat - <<EOF
+server "$domain" {
+	listen on $ipv4 port http
+	listen on $ipv6 port http
+	listen on $ipv4 tls port https
+	listen on $ipv6 tls port https
+	no log
+
+	alias "$domain_v4"
+	alias "$domain_v6"
+
+	tls {
+		certificate "/etc/ssl/$domain.fullchain.pem"
+		key "/etc/ssl/private/$domain.key"
+	}
+
+	location "/.well-known/acme-challenge/*" {
+		root "/acme"
+		request strip 2
+	}
+
+	root "/htdocs/$domain"
+	location "/ip" { fastcgi }
+EOF
+
+for _c in $(list_codes 1xx); do
+	print_block_return "$_c"
+done
+for _c in $(list_codes 2xx); do
+	print_block_return "$_c"
+done
+for _c in $(list_codes 3xx); do
+	print_block_return "$_c" "/"
+done
+for _c in $(list_codes 4xx); do
+	print_block_return "$_c"
+done
+for _c in $(list_codes 5xx); do
+	print_block_return "$_c"
+done
+
+printf "}\n"
diff --git a/utils/httpd/gen-index.sh b/utils/httpd/gen-index.sh
new file mode 100644
index 0000000..8e8081f
--- /dev/null
+++ b/utils/httpd/gen-index.sh
@@ -0,0 +1,114 @@
+#!/bin/sh
+# httpd-utils
+# Written in 2020 by Lucas
+# CC0 1.0 Universal/Public domain - No rights reserved
+#
+# To the extent possible under law, the author(s) have dedicated all
+# copyright and related and neighboring rights to this software to the
+# public domain worldwide. This software is distributed without any
+# warranty. You should have received a copy of the CC0 Public Domain
+# Dedication along with this software. If not, see
+# <http://creativecommons.org/publicdomain/zero/1.0/>.
+
+usage()
+{
+	printf "Usage: %s domain domain_v4 domain_v6\n" "${0##*/}" >&2
+	exit 1
+}
+
+list_codes()
+{
+	case $1 in
+	1xx)	q='1[0-9][0-9]' ;;
+	2xx)	q='2[0-9][0-9]' ;;
+	3xx)	q='3[0-9][0-9]' ;;
+	4xx)	q='4[0-9][0-9]' ;;
+	5xx)	q='5[0-9][0-9]' ;;
+	*)	q=X ;;
+	esac
+	grep -x -- "$q" codes.txt
+}
+
+show_category()
+{
+	_t=$1 _cc=$2
+	cat - <<EOF
+		<dl>
+			<dt>$_t $_cc</dt>
+EOF
+
+	for _c in $(list_codes "$_cc"); do
+		printf '\t\t\t<dd><a href="/c/%u">%u</a></dd>\n' "$_c" "$_c"
+	done
+	printf "\t\t</dl>\n"
+}
+
+[ $# -eq 3 ] || usage
+domain=$1 domain_v4=$2 domain_v6=$3
+
+cat - <<EOF
+<!DOCTYPE html>
+<html>
+	<head>
+		<meta charset="UTF-8" />
+		<title>$domain</title>
+		<style>
+* {
+	margin: 0;
+	padding: 0;
+}
+
+body {
+	width: 800px;
+	margin: 20px auto;
+	font-size: 16px;
+	line-height: 20px;
+}
+
+h1,
+h2,
+dl {
+	margin-bottom: 20px;
+}
+
+dd {
+	margin-left: 20px;
+}
+
+h1 {
+	font-size: 32px;
+	line-height: 40px;
+}
+
+h2 {
+	font-size: 24px;
+	line-height: 40px;
+}
+		</style>
+	</head>
+	<body>
+		<h1>$domain</h1>
+
+		<h2>Utilities</h2>
+		<dl>
+			<dt><a href="/ip">/ip</a></dt>
+			<dd>shows client IP.</dd>
+			<dt><a href="//$domain_v4/ip">$domain_v4/ip</a></dt>
+			<dd>shows client IP, only listens on a IPv4 address.</dd>
+			<dt><a href="//$domain_v6/ip">$domain_v6/ip</a></dt>
+			<dd>shows client IP, only listens on a IPv6 address.</dd>
+		</dl>
+
+		<h2>HTTP status codes</h2>
+EOF
+
+show_category "Informational" 1xx
+show_category "Successful" 2xx
+show_category "Redirection" 3xx
+show_category "Client Error" 4xx
+show_category "Server Error" 5xx
+
+cat - <<EOF
+	</body>
+</html>
+EOF
diff --git a/utils/httpd/ip.c b/utils/httpd/ip.c
new file mode 100644
index 0000000..e4bdc8f
--- /dev/null
+++ b/utils/httpd/ip.c
@@ -0,0 +1,31 @@
+/*
+ * httpd-utils
+ * Written in 2020 by Lucas
+ * CC0 1.0 Universal/Public domain - No rights reserved
+ *
+ * To the extent possible under law, the author(s) have dedicated all
+ * copyright and related and neighboring rights to this software to the
+ * public domain worldwide. This software is distributed without any
+ * warranty. You should have received a copy of the CC0 Public Domain
+ * Dedication along with this software. If not, see
+ * <http://creativecommons.org/publicdomain/zero/1.0/>.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+int
+main(void)
+{
+	char *ip;
+
+	ip = getenv("HTTP_X_FORWARDED_FOR");
+	if (ip == NULL)
+		ip = getenv("REMOTE_ADDR");
+	if (ip == NULL)
+		ip = "unknown";
+
+	printf("Content-type: text/plain\n\n%s\n", ip);
+
+	return 0;
+}