diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000..ba53ff6
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "test/bach"]
+	path = test/bach
+	url = https://github.com/bach-sh/bach.git
diff --git a/test/bach b/test/bach
new file mode 160000
index 0000000..d7855b4
--- /dev/null
+++ b/test/bach
@@ -0,0 +1 @@
+Subproject commit d7855b402da74fee5efba937b012ed2275821bf9
diff --git a/test/ufw-docker.test.sh b/test/ufw-docker.test.sh
new file mode 100755
index 0000000..3e43a10
--- /dev/null
+++ b/test/ufw-docker.test.sh
@@ -0,0 +1,201 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+working_dir="$(cd "$(dirname "$BASH_SOURCE")"; pwd -P)"
+source "$working_dir"/bach/bach.sh
+
+@setup-test {
+    @mocktrue ufw status
+    @mocktrue grep -Fq "Status: active"
+}
+
+function ufw-docker() {
+    @source <(@sed -n '/^# __main__$/,$p' "$working_dir/../ufw-docker") "$@"
+}
+
+test-ufw-docker-help() {
+    ufw-docker help
+}
+test-ufw-docker-help-assert() {
+    ufw-docker--help
+}
+
+
+test-ufw-docker-without-parameters() {
+    ufw-docker
+}
+test-ufw-docker-without-parameters-assert() {
+    test-ufw-docker-help-assert
+}
+
+
+test-ufw-is-disabled() {
+    @mockfalse grep -Fq "Status: active"
+
+    ufw-docker
+}
+test-ufw-is-disabled-assert() {
+    die "UFW is disabled or you are not root user."
+    ufw-docker--help
+}
+
+
+test-ufw-docker-status() {
+    ufw-docker status
+}
+test-ufw-docker-status-assert() {
+    ufw-docker--status
+}
+
+
+test-ufw-docker-install() {
+    ufw-docker install
+}
+test-ufw-docker-install-assert() {
+    ufw-docker--install
+}
+
+
+test-ufw-docker-check() {
+    ufw-docker check
+}
+test-ufw-docker-check-assert() {
+    ufw-docker--check
+}
+
+
+test-ufw-docker-service() {
+    ufw-docker service allow httpd
+}
+test-ufw-docker-service-assert() {
+    ufw-docker--service allow httpd
+}
+
+
+test-ufw-docker-raw-command() {
+    ufw-docker raw-command status
+}
+test-ufw-docker-raw-command-assert() {
+    ufw-docker--raw-command status
+}
+
+
+test-ufw-docker-add-service-rule() {
+    ufw-docker add-service-rule httpd 80/tcp
+}
+test-ufw-docker-add-service-rule-assert() {
+    ufw-docker--add-service-rule httpd 80/tcp
+}
+
+
+test-ASSERT-FAIL-ufw-docker-delete-must-have-parameters() {
+    ufw-docker delete
+}
+
+
+test-ASSERT-FAIL-ufw-docker-list-must-have-parameters() {
+    ufw-docker list
+}
+
+
+test-ASSERT-FAIL-ufw-docker-allow-must-have-parameters() {
+    ufw-docker allow
+}
+
+
+test-ASSERT-FAIL-ufw-docker-delete-httpd-but-it-doesnt-exist() {
+    @mockfalse ufw-docker--instance-name httpd
+    ufw-docker delete httpd
+}
+
+
+test-ASSERT-FAIL-ufw-docker-list-httpd-but-it-doesnt-exist() {
+    @mockfalse ufw-docker--instance-name httpd
+    ufw-docker list httpd
+}
+
+
+test-ASSERT-FAIL-ufw-docker-allow-httpd-but-it-doesnt-exist() {
+    @mockfalse ufw-docker--instance-name httpd
+    ufw-docker allow httpd
+}
+
+
+test-ufw-docker-list-httpd() {
+    @mock ufw-docker--instance-name httpd === @stdout httpd-container-name
+    ufw-docker list httpd
+}
+test-ufw-docker-list-httpd-assert() {
+    ufw-docker--list httpd-container-name "" ""
+}
+
+
+test-ufw-docker-allow-httpd() {
+    @mock ufw-docker--instance-name httpd === @stdout httpd-container-name
+    ufw-docker allow httpd
+}
+test-ufw-docker-allow-httpd-assert() {
+    ufw-docker--allow httpd-container-name "" ""
+}
+
+
+test-ufw-docker-allow-httpd-80() {
+    @mock ufw-docker--instance-name httpd === @stdout httpd-container-name
+    ufw-docker allow httpd 80
+}
+test-ufw-docker-allow-httpd-80-assert() {
+    ufw-docker--allow httpd-container-name 80 ""
+}
+
+
+test-ufw-docker-allow-httpd-80tcp() {
+    @mock ufw-docker--instance-name httpd === @stdout httpd-container-name
+    ufw-docker allow httpd 80/tcp
+}
+test-ufw-docker-allow-httpd-80tcp-assert() {
+    ufw-docker--allow httpd-container-name 80 ""
+}
+
+
+test-ufw-docker-allow-httpd-80udp() {
+    @mock ufw-docker--instance-name httpd === @stdout httpd-container-name
+    ufw-docker allow httpd 80/udp
+}
+test-ufw-docker-allow-httpd-80udp-assert() {
+    ufw-docker--allow httpd-container-name 80 udp
+}
+
+
+test-ASSERT-FAIL-ufw-docker-allow-httpd-INVALID-port() {
+    @mock ufw-docker--instance-name httpd === @stdout httpd-container-name
+    @mock die 'invalid port syntax: "invalid".' === exit 1
+
+    ufw-docker allow httpd invalid
+}
+
+
+test-ufw-docker-list-httpd() {
+    @mock ufw-docker--instance-name httpd === @stdout httpd-container-name
+    ufw-docker list httpd
+}
+test-ufw-docker-list-httpd-assert() {
+    ufw-docker--list httpd-container-name "" ""
+}
+
+
+test-ufw-docker-delete-allow-httpd() {
+    @mock ufw-docker--instance-name httpd === @stdout httpd-container-name
+    ufw-docker delete allow httpd
+}
+test-ufw-docker-delete-allow-httpd-assert() {
+    ufw-docker--delete httpd-container-name "" ""
+}
+
+
+test-ASSERT-FAIL-ufw-docker-delete-only-supports-allowed-rules() {
+    @mock ufw-docker--instance-name httpd === @stdout httpd-container-name
+    ufw-docker delete non-allow
+}
+test-ASSERT-FAIL-ufw-docker-delete-only-supports-allowed-rules-assert() {
+    die "\"delete\" command only support removing allowed rules"
+}
diff --git a/ufw-docker b/ufw-docker
index 6a2acba..a081ee6 100755
--- a/ufw-docker
+++ b/ufw-docker
@@ -382,6 +382,8 @@ function die() {
     exit 1
 }
 
+# __main__
+
 if ! ufw status 2>/dev/null | grep -Fq "Status: active" ; then
     die "UFW is disabled or you are not root user."
 fi