diff --git a/checks.py b/checks.py
index e325a74..72ea969 100644
--- a/checks.py
+++ b/checks.py
@@ -8,9 +8,9 @@ import bare, re
 def admin(
     bot: bare.bot,
     name: str,
-    host: Optional[str] = "nul",
-    chan: Optional[str] = "nul",
-    cmd: Optional[str] = "nul",
+    host: Optional[str] = "",
+    chan: Optional[str] = "",
+    cmd: Optional[str] = "",
 ) -> bool:
     if (
         name.lower() in conf.servers[bot.server]["admins"]
@@ -20,13 +20,13 @@ def admin(
         if bot.current != "bridge":
             return True
         else:
-            if type(chan) != str or chan == "nul":
+            if not chan:
                 return False
             else:
                 bot.msg(f"Sorry {name}, bridged users can't use admin commands.", chan)
                 return False
     else:
-        if type(chan) != str or chan == "nul":
+        if not chan:
             return False
         else:
             bot.msg(f"Sorry {name}, {cmd} is an admin only command.", chan)
diff --git a/config.py b/config.py
index 0236fbb..9a853f8 100644
--- a/config.py
+++ b/config.py
@@ -67,8 +67,9 @@ def mfind(message: str, find: list, usePrefix: bool = True) -> bool:
     else:
         return any(message[: len(match)] == match for match in find)
 
-def sub(message: str, bot: bare.bot, chan: Optional[str], name: Optional[str]):
+def sub(message: str, bot: bare.bot, chan: Optional[str] = "", name: Optional[str] = "") -> str:
     result = message.replace("$BOTNICK", bot.nick).replace("$NICK", bot.nick)
+    result = result.replace("$NICKLEN", str(bot.nicklen)).replace("$MAX", str(bot.nicklen))
     if chan:
         result = result.replace("$CHANNEL", chan).replace("$CHAN", chan)
     if name:
diff --git a/handlers.py b/handlers.py
index 3d360e5..a0bab1e 100644
--- a/handlers.py
+++ b/handlers.py
@@ -99,9 +99,9 @@ def PRIVMSG(bot: bare.bot, msg: str) -> Union[tuple[None, None], tuple[str, str]
     for cmd in cmds.data:
         triggers = [cmd]
         triggers.extend(cmds.data[cmd]["aliases"])
-        triggers = list(call.replace("$BOTNICK", bot.nick.lower()) for call in triggers)
+        triggers = list(conf.sub(call, bot, chan, name).lower() for call in triggers)
         if conf.mfind(
-            message.lower(),
+            conf.sub(message, bot, chan, name).lower(),
             triggers,
             cmds.data[cmd]["prefix"],
         ):
@@ -115,7 +115,7 @@ def PRIVMSG(bot: bare.bot, msg: str) -> Union[tuple[None, None], tuple[str, str]
     if not handled:
         for check in cmds.regexes:
             if re.search(
-                check.replace("$MAX", str(bot.nicklen)).replace("$BOTNICK", bot.nick),
+                conf.sub(check, bot, chan, name),
                 message,
             ):
                 cmds.call[check](bot, chan, name, message)