diff --git a/README.md b/README.md
index fffd221..71b50f6 100644
--- a/README.md
+++ b/README.md
@@ -1,15 +1,17 @@
 # irc_bot
 
-About a cats
+About cats
+
+Inspired from https://github.com/go-chat-bot/plugins/blob/master/catfacts/catfacts.go
 
 ```go
 go build
 ```
 
 ```sh
-export CTF2021NICK="HaX0r666"
-export CTF2021PASS="passw0rd"
-export CTF2021URL="localhost:6667"
-./ctf2021_ircbot
+export IRC_NICK="HaX0r666"
+export IRC_USER="mamin_simpotyaga"
+export IRC_PASS="passw0rd"
+export IRC_URL="localhost:6667"
+./ctf2021_ircbot | tee bot.log
 ```
-
diff --git a/main.go b/main.go
index 6cf1946..f0e6c7b 100644
--- a/main.go
+++ b/main.go
@@ -17,7 +17,7 @@ import (
 )
 
 var channel = "#ctf"
-var sendWelcome = ""
+var sendHi = ""
 
 const (
 	pattern   = "(?i)\\b(cat|gato|miau|meow|garfield|lolcat|кот|кошк)[s|z]{0,1}\\b"
@@ -26,6 +26,16 @@ const (
 	gifPrefix = "Meow! Here's a gif: %s ^_^"
 )
 
+// environment variables
+const (
+	userEnv  = "IRC_USER"
+	nickEnv  = "IRC_NICK"
+	himsgEnv = "IRC_SEY_HI"
+	passEnv  = "IRC_PASS"
+	chanEnv  = "IRC_CHAN"
+	urlEnv   = "IRC_URL"
+)
+
 type catFact struct {
 	Fact   string `json:"fact"`
 	Length int    `json:"length"`
@@ -81,25 +91,20 @@ func (s *stats) printStats(e *irc.Event) {
 	s.realStats(e)
 }
 
-func main() {
-	nick := os.Getenv("CTF2021NICK")
-	irccon := irc.IRC(nick, os.Getenv("CTF2021USER"))
-
-	s := newStats()
-
-	irccon.VerboseCallbackHandler = false
-	irccon.Debug = false
-	irccon.UseTLS = false
-
+func addCallbacks(irccon *irc.Connection, s *stats) {
 	irccon.AddCallback("001", func(e *irc.Event) {
 		log.Println("Welcome message:", e.Message())
 
-		e.Connection.Privmsg("nickserv", "identify "+os.Getenv("CTF2021PASS"))
+		// Login
+		e.Connection.Privmsg("nickserv", "identify "+os.Getenv(passEnv))
 
-		if sendWelcome != "" {
-			e.Connection.Join(channel)
-			e.Connection.Privmsg(channel, `I'm a cat bot!`)
-			e.Connection.Privmsg(channel, `Inspired from https://github.com/go-chat-bot/plugins/blob/master/catfacts/catfacts.go`)
+		// Join to channel
+		e.Connection.Join(channel)
+
+		// Greetings
+		if sendHi != "" {
+			e.Connection.Privmsg(channel, `Hi!`)
+			e.Connection.Privmsg(channel, `I'm a cat facts bot!`)
 			e.Connection.Privmsg(channel, `Try cat /etc/passwd :p`)
 			e.Connection.Privmsg(channel, `Source code and issue tracker: https://gitea.difrex.ru/CTF2021/irc_bot`)
 			e.Connection.Privmsg(channel, `Now with gifs! ^_^`)
@@ -111,8 +116,21 @@ func main() {
 		s.addUser(e.Nick)
 		doCommand(e.Message(), e, s)
 	})
+}
 
-	err := irccon.Connect(os.Getenv("CTF2021URL"))
+func main() {
+	nick := os.Getenv(nickEnv)
+	irccon := irc.IRC(nick, os.Getenv(userEnv))
+
+	s := newStats()
+
+	irccon.VerboseCallbackHandler = false
+	irccon.Debug = false
+	irccon.UseTLS = false
+
+	addCallbacks(irccon, s)
+
+	err := irccon.Connect(os.Getenv(urlEnv))
 	if err != nil {
 		fmt.Printf("Err %s", err)
 		return
@@ -195,10 +213,10 @@ func catFacts(con *irc.Connection) (string, error) {
 }
 
 func init() {
-	ch := os.Getenv("CTF2021CHANNEL")
+	ch := os.Getenv(chanEnv)
 	if ch != "" {
 		channel = ch
 	}
 
-	sendWelcome = os.Getenv("CTF2021WC")
+	sendHi = os.Getenv(himsgEnv)
 }