diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..5435769
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,20 @@
+all:
+
+DOMAIN ?= karchnu.fr
+get-certificate-info:
+	openssl s_client -connect $(DOMAIN):443
+
+show-connected-ipv4:
+	@# Don't forget the double $$ since we are in a Makefile.
+	@netstat -n -p tcp | drop-until tcp | awk '{print $$5}' | cut -d. -f 1-4 | sort | uniq
+
+detect-volume:
+	ffmpeg -i $(SRC) -af "volumedetect" -vn -sn -dn -f null /dev/null
+
+PORT ?=
+which-bin-uses-this-port:
+	fstat | grep ':$(PORT)'
+
+MAIL_DOMAIN ?= mail.karchnu.fr
+verify-mail-certificate:
+	echo | openssl s_client -starttls smtp -showcerts -connect $(MAIL_DOMAIN):587 -servername $(MAIL_DOMAIN) | openssl x509 -noout -dates