diff --git a/tools/mail.py b/tools/mail.py
new file mode 100755
index 00000000..d977a7aa
--- /dev/null
+++ b/tools/mail.py
@@ -0,0 +1,87 @@
+#!/usr/bin/python3
+
+import sys, sqlite3, subprocess
+
+# Load STORAGE_ROOT setting from /etc/mailinabox.conf.
+env = { }
+for line in open("/etc/mailinabox.conf"): env.setdefault(*line.strip().split("=", 1))
+
+# Connect to database.
+conn = sqlite3.connect(env["STORAGE_ROOT"] + "/mail/users.sqlite")
+c = conn.cursor()
+
+if len(sys.argv) < 2:
+	print("Usage: ")
+	print("  scripts/mail_db_tool.py user  (lists users)")
+	print("  scripts/mail_db_tool.py user add user@domain.com [password]")
+	print("  scripts/mail_db_tool.py user password user@domain.com [password]")
+	print("  scripts/mail_db_tool.py user remove user@domain.com")
+	print("  scripts/mail_db_tool.py alias  (lists aliases)")
+	print("  scripts/mail_db_tool.py alias add incoming.name@domain.com sent.to@other.domain.com")
+	print("  scripts/mail_db_tool.py alias remove incoming.name@domain.com")
+	print()
+	print("Removing a mail user does not delete their mail folders on disk. It only prevents IMAP/SMTP login.")
+	print()
+
+elif sys.argv[1] == "user" and len(sys.argv) == 2:
+	c.execute('SELECT email FROM users')
+	for row in c.fetchall():
+		print(row[0])
+
+elif sys.argv[1] == "user" and sys.argv[2] in ("add", "password"):
+	if len(sys.argv) < 5:
+		if len(sys.argv) < 4:
+			email = input("email: ")
+		else:
+			email = sys.argv[3]
+		pw = input("password: ")
+	else:
+		email, pw = sys.argv[3:5]
+
+	# hash the password
+	pw = subprocess.check_output(["/usr/bin/doveadm", "pw", "-s", "SHA512-CRYPT", "-p", pw]).strip()
+
+	if sys.argv[2] == "add":
+		try:
+			c.execute("INSERT INTO users (email, password) VALUES (?, ?)", (email, pw))
+		except sqlite3.IntegrityError:
+			print("User already exists.")
+			sys.exit(1)
+			
+		# Create the user's INBOX and subscribe it.
+		conn.commit() # write it before next step
+		subprocess.check_call(["doveadm", "mailbox", "create", "-u", email, "-s", "INBOX"])
+	elif sys.argv[2] == "password":
+		c.execute("UPDATE users SET password=? WHERE email=?", (pw, email))
+		if c.rowcount != 1:
+			print("That's not a user.")
+			sys.exit(1)
+
+elif sys.argv[1] == "user" and sys.argv[2] == "remove" and len(sys.argv) == 4:
+	c.execute("DELETE FROM users WHERE email=?", (sys.argv[3],))
+	if c.rowcount != 1:
+		print("That's not a user.")
+		sys.exit(1)
+
+elif sys.argv[1] == "alias" and len(sys.argv) == 2:
+	c.execute('SELECT source, destination FROM aliases')
+	for row in c.fetchall():
+		print(row[0], "=>", row[1])
+
+elif sys.argv[1] == "alias" and sys.argv[2] == "add" and len(sys.argv) == 5:
+	try:
+		c.execute("INSERT INTO aliases (source, destination) VALUES (?, ?)", (sys.argv[3], sys.argv[4]))
+	except sqlite3.IntegrityError:
+		print("Alias already exists.")
+		sys.exit(1)
+
+elif sys.argv[1] == "alias" and sys.argv[2] == "remove" and len(sys.argv) == 4:
+	c.execute("DELETE FROM aliases WHERE source=?", (sys.argv[3],))
+	if c.rowcount != 1:
+		print("That's not an alias.")
+		sys.exit(1)
+
+else:
+	print("Invalid command-line arguments.")
+
+conn.commit()