diff --git a/server/client_resp.go b/server/client_resp.go
index 30a8f87..cfcaf5d 100644
--- a/server/client_resp.go
+++ b/server/client_resp.go
@@ -12,7 +12,6 @@ import (
 	"net"
 	"runtime"
 	"strconv"
-	"strings"
 	"time"
 )
 
@@ -124,7 +123,7 @@ func (c *respClient) handleRequest(reqData [][]byte) {
 		c.cmd = ""
 		c.args = reqData[0:0]
 	} else {
-		c.cmd = strings.ToLower(hack.String(reqData[0]))
+		c.cmd = hack.String(lowerSlice(reqData[0]))
 		c.args = reqData[1:]
 	}
 	if c.cmd == "quit" {
diff --git a/server/util.go b/server/util.go
index a243c18..7c5b73d 100644
--- a/server/util.go
+++ b/server/util.go
@@ -123,3 +123,14 @@ func ReadRequest(in *bufio.Reader, a *arena.Arena) ([][]byte, error) {
 
 	return req, nil
 }
+
+func lowerSlice(buf []byte) []byte {
+	for i, r := range buf {
+		if 'A' <= r && r <= 'Z' {
+			r += 'a' - 'A'
+		}
+
+		buf[i] = r
+	}
+	return buf
+}